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MG Midget and Sprite Technical Electrical weirdness BBS discussion at MG-Cars.net
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MG Midget and Sprite Technical - Electrical weirdness
| Sorting electrics as I close in on the completion of my Canadian 71 midget rebuild. Removed, cleaned, replaced fuse box. Rebuilt headlight switch. Everything works now but whenever I activate the indicators or sidelights the fuel pump blips. It blips on each flash of the indicators and each on/off of the sidelight switch. What does this imply? Seems to me that this is odd...
Thoughts would be much appreciated as my electrical expertise is pretty much limited to taking things apart, cleaning them, and putting them back together again... |
| Simon Fryer |
| When you replaced the fuse box, did you fit it in the same orientation? The two sidelight fuses are linked together and if you fit the fuse box the wrong way, strange things can happen. There is a link on the back of the fuse box - check that it is linking the two fuses with the red wires connected, not the brown/purple to the White/green. |
| Dave O'Neill 2 |
| Thanks Dave, I double-checked the fuse box and appear to have everything in order. I've cleaned up wiring and earthing for each light unit as well as for the fuel pump so am now a bit stuck. Are there earth points behind the dash that I should be examining to address this? |
| Simon Fryer |
| Are you turn indicators connected with the ignition? I appreciate the lights operate without the ignition having to be on so I can see there maybe some sort of feed glitch. For your indicators I would expect the pump to be running anyway as you would have to have your ignition on. When I look at the four-fuse box (uk only has two) I could see how Dave's explanation would have covered some quite peculiar behaviour! |
| Graeme Williams |
| Are you sure your not mistaking the fuel pump ticing on and off as it should as an electrical fault The SU fuel pump it supposed to tic on and off at random times to pressurise the system to the carbs The sound of a signal flasher and the SU fuel pump ticing are very similar in sound and tempo Prop |
| 1 Paper |
| Graeme & Prop,
this issue is only present with ignition on. I am used to the fuel pump ticking randomly and it does that as normal as long as I leave the indicators and light switch alone. As soon as I turn on either indicator the pump begins a perfectly synchronised ticking with the lights flashing. When I operate the light switch it ticks each time the switch clicks over. I'm quite sure I'm not mixing the sounds up (it's not far from the fuel pump to the dash on a midget) and without indicators flashing or me flipping the light switch the pump behaves entirely as I would expect. Could it be a ground fault somewhere in the column/dash area? Many thanks. S |
| Simon Fryer |
| Nah... its not a gound issue, cuz its working (incorrectly)
Some how you have got the power wire to the fuel pump installed AFTER the flasher unit of the indicators Basically your fuel pump thinks its a indicator The flasher thats doing this is the one under the bonnet on the fire wall close to the steering wheel. Most likely you got a wire misplaced on the fuse box Btw... the ground for the fuel pump is attached to the wheel well next to the fuelbpump amd does not go back to the wiring harness Id install a battery isolator switch before you go much further at least untill you get this sorted to avoid any electrical fires and also disconnect the battery when not in use to avoid any fires Prop |
| 1 Paper |
| Clair lives in canada...but not sure where. If she is close she could come by if asked nicely to play with your ... "wiring" I know She is very talented in midgets and other old clasics Prop |
| 1 Paper |
| 'it's not far from the fuel pump to the dash on a midget' Simon, on a '71 Midget the fuel pump is under the rear of the car next to the axle, on the right hand side. So if you are seated in the car the dash is in front but the pump sound will be coming from behind you - unless your car has been 'modified' by a PO and the pump has been moved. If the latter then the wiring will have been messed around with too. Can you describe with as much detail as possible what you've got? |
| David Smith |
| Prop, it is a very long way from here in Ontario to Saskatchewan. Think of it as driving from your state to Colorado or about there. No small trip. Canada is bigger than the United States. Clare |
| Clare Ravenwood |
| LOL Clare |
| Dave O'Neill 2 |
| Out of interest, Google reckons it's easily 1000 miles from Ontario to Saskatchewan. The UK is so small.... |
| Rob Armstrong |
| it's only a little less from Land's End to John O'Groats... |
| David Smith |
| Prop - Clare is right: it's a really, really long way from Ontario to Saskatchewan. I towed my Midget here from Ontario (took 4 days).
Dave - the fuel pump is in it's place above the axle. If I lean into the cockpit from the fuel pump (passenger) side and flip on ignition and indicators, I have the fuel pump blipping in my left ear and the indicators clicking in my right. I've made sure the earth and wiring at the pump are secure. Prop - a concrete theory - love it. I've checked the fuse box against the wiring diagram several times. What could I have misplaced to cause such mayhem? Is it possible that the wiring could be mixed up somewhere else (column?)? Thanks everyone! S |
| Simon Fryer |
| Just checked the wiring to the fuse block again - all looks as it should... |
| Simon Fryer |
| Do you have a spare pump to test ? Have you had the engine running yet and if so is the charging circuit working ? Is battery voltage good ? My initial thought was earth related. |
| richard b |
| Could a voltage drop associated with the sudden extra load cause the pump to kick? After all, it is operated by magnetic forces which depend on voltage. |
| Graeme Williams |
| I know Dave has already alerted you to check the fitting of the fuse block, and you say you have checked it (twice , at least!) but the fault does sound as if it could be caused by this.
If you remove the box cover, there should be small raised numbers on the base - they are easy to miss. 1 and 2 must be at the forward facing (downhill) end of the base. If the wires are all connected in the right relative positions, but the base is the wrong way round then the wrong connections will be made because of the hidden link on the underside. There are also numbers on the base. The link connects terminals 1 and 3 If you remove fuse 3 (2nd from the top) this should leave the pump connected when the ignition is switched on, so it will tick, but should isolate it from all circuts other than the ignition. You could try this and see what happens.  |
| GuyW |
| Simon,
as well as the advice already given have you tried to see if the problem remains the same or varies if you start the engine and have it running at say 1,500 revs? I'm thinking of the very basics of the battery being in good condition and fully charged as well as the battery posts, clamps and leads all being clean, secure and protected, same for all other connections and earths. Thinking of what prop put, does your car have hazard lights, or like many others by now, have any variations from factory fittings and wiring? |
| Nigel Atkins |
| Simon, how about putting up on here a hi-res close-up photo of your fuse box with the cover off and noting which side is parallel to the windscreen (if you've not all ready sorted it from previous suggestions). |
| Nigel Atkins |
| Sorry clair and simon... i know canada is huge but im not aware of its geography
1000 miles...eehhhhh, just drive faster...haha There is an easy solution... run a new power wire and clip the old, its grounded at the pump His car would have hazards but there on a some what differant circuit then the indicators the haszard flasher unit is inside the radio concel while the indicator flasher is inside the engine bay on the fire wall on the right side of the car (usa passange side) I like the thinking about the low voltage his simons car would have the generator along with the mechanical regulator instead of the alt. And wont start charging until around 2200 to 2600 rpm ? The thing that makes me still think the power wire to the pump is connected after the indicator flasher in the engine bay is becuz simion says the pump kicks on and off in unison with the indicators when there activated...so im still stuck on that Prop |
| 1 Paper |
| OK - lots of things to address here. Thanks so much everybody.
Richard: No, I don't have a spare pump to test. I am reluctant to try to run the engine while this anomaly exists but believe the battery to be in good shape. Graeme: how would someone who owns a multimeter but doesn't really understand it, check that? Guy: everything looks correct with the fuse block to me. It is pointing downwards and if I remove fuse 3 the pump operates normally (as it does if I do not operate light switch, indicators or hazards). If I operate the light switch with fuse 3 removed the pump clicks in sympathy. Nigel: I'm pretty sure the battery and its connections are good, and as mentioned above am reluctant to try to start the engine with this fault present. My car does have hazards (pump happily clicks in sync with them too) and there is very little hacking around of the wiring. No additions, just omissions: no door switches for interior light, no seat belt warning system. Wires for these are blanked off where they would connect behind console and under seats. Pic shows my fuse block: top is windscreen side so facing down to fuse 1. Fuse 4 left side purple/right=brown. fuse 3 l=green/ r=white. fuse 1 & 2 left - all red / right red w/green tracer. Prop: I'm not sure that running a new wire is an easy solution for someone of my limited skills... You are correct re hazards etc. Wiring to indicators goes through the hazard switch so if hazard switch malfunctions I think indicators cease to operate. My car does have an alternator. The logic of your last point appeals to me. How could the pump be connected after the flasher? Thanks again everyone!  |
| Simon Fryer |
| When you turn on the ignition, does the pump run until the carburetor pressure stops it? I think you said it did. And if I have got this right, using the indicators or lights make is "click" again? So under normal conditions the pump has power to it apparently correctly. Why don't you put a voltage tester between the power terminal on the pump and the metal bodywork and with the indicators working see whether the voltage signal changes in any way? |
| Graeme Williams |
| ****Guy:
everything looks correct with the fuse block to me. It is pointing downwards and if I remove fuse 3 the pump operates normally (as it does if I do not operate light switch, indicators or hazards). If I operate the light switch with fuse 3 removed the pump clicks in sympathy**** Okay... that says alot right there...it would appear that you have the correct wire going to the pump and from the indicators power wire going into the power wire to the pump. So the pump is getting 2 sources of juice ****The logic of your last point appeals to me. How could the pump be connected after the flasher? **** Thats a good question but the flasher is driving the pump at the same time its driving the indicators I have to appologise ...i thought the hazords where unaffected If your car is an american 1971 it should have a generator Is your alt a lucas? Or is it a differant make and what kind of voltage regulator.... i dont know that this means much, but just to get everyone on the same page Sadly my auto electric skill are just good enough to start a good ol electeic fire Let me look at Mr haynes for a few minutes and see what i can glen Prop |
| 1 Paper |
| Simon, being a N American model there is an isolating diode between the seatbelt warning circuit and door/gearbox switches. This diode prevents the unswitched power through fuse 4 getting to the switched power through fuse 3. If this has gone short circuit it could cause strange faults like the car will continue to run when the ignition switch is off until you open the drivers door. I have no idea where this diode is located though, it wasn't fitted to UK cars.
I note you say "no door switches for interior light, no seat belt warning system" so maybe a PO has been playing around to cure this problem without success? If you have a Haynes manual the diode is marked 203. Rob |
| MG Moneypit |
| Graeme: you have understood the situation perfectly. I'll try the voltage test. Prop: So at some point there is a junction which is allowing power to travel from the indicators, sidelights, hazards to the pump? Alternator looks standard Lucas. Car is a Dec '71 manufacture so maybe counts as '72? |
| Simon Fryer |
| Thanks...if the car is dec 71, then most likely it is set up as a 1972 I love what rob said...that makes alot of sence...i wasnt aware of a diode ...im hunting for it now Simon....post your email and i make a crude copy of the haynes wiring scamnic for you . |
| 1 Paper |
| Simon,
IF I understand your photo correctly then the wiring seems right as long as the link in the fuse box is between the two bottom fuses on the rhs (see below). I know very little about electricary so please note Rob's comment. Omissions in wiring can also be, but not necessarily in your case, hacking to wiring. Always, always, with any electrical or ignition faults it pays to check and double check that the battery is in good condition and fully charged as even if it's not part of the fault now it can possibly introduce or expand a faulty later.  |
| Nigel Atkins |
| Rob:
I know where the diode is (left of the steering column on the way to the ignition key/seatbelt warning buzzer)PG wire leading to buzzer - NR into the seatbelt warning system. No door switches and no place for them that I can see. PO replaced panels with earlier ones without spots for switches? When the car was running - 15 years ago - electrics were the same and worked ok. Would the diode be doing anything without door switches? Prop: I have the wiring schematic both in Bentley and online. I note that the White wire from the pump junctions with the White wire through the ignition switch to the tach. A Green wire comes off the tach to the hazards I wonder if there's something unpleasant going on back there... If only it was more than 36F outside S |
| Simon Fryer |
| Simon, I'm not saying there are any in your case but beware of errors in the schematics of Bentley, Haynes, online and even, hush my mouth, Drivers Handbook. Have you got the correct factory Drivers Handbook for your model and year of car as that will have a schematic. I'll have a look on my DVD and see if there's anything close. |
| Nigel Atkins |
| Hazard switch - have you tried rocking it on/off for a good few times and checked/cleaned the connections to and from and from anything to do with hazards and indicators? |
| Nigel Atkins |
| Yepp...thats about what i traced down in the haynes
I dont know about that inline diode, thats a long shaky path to effect the fuel pump Im wondering if there is some kind of (path) thats connecting the green to the white The fuel pump is direct it goes from the ignition switch to the fuse box and straight to the fuel pump Id try this as a test to see what happens...pull the 2 white wires off the fuse box and run a jumper wire between the 2 white wires (connecting the 2 whites togather and taking the fuse box out of play) If the fuel pump works fine... then the problem is ither in one of 3 problems as i can tell, 1. the ignition switch 2. The diode 3. Fuse box If doing my test above with the jumper wire makes the pump work properly as it should then the super easy red neck fix would be to get an INLINE fuse and put it in place of the jumper wire and take it out of play from the rest of the circuit Id get a couple of wire connector spades thst will fit onto the white wires and soilder the new connectors onto the inline fuse...that way your not cutting and hacking into your cars wiring system All your doing is by passing the cars fuse with an independant dedicated fuse for the fuel pump... There is a reason British wiring is known as the prince of darkness...haha Prop |
| 1 Paper |
| Correction....i mis typed If on the test i out lined above... if the pump still does NOT work properly and acts as before then that would indicate that its the diode failed and the power is being feed back thur the system Sorry about that Also... i wouldnt get hung up on the ignition switch...that is not very likely its more of a last gasph remote idea...ive never heard of a dodgy ignition switch causing this kind of problem Prop |
| 1 Paper |
| Prop: I'm not understanding the fuse box bypass. The two white wires are already linked where they attach to the box - see Nigel's diagram above. Would a bypass involve connecting a jumper from the white wires to the greens? I tried that and the problem remained. I did however have a good look at the diode which appears to have been the victim of some PO bodgery. Lots of electrical tape... Is there some way to test the diode to see if it is defunct? |
| Simon Fryer |
| id way say google how to test a diode..im afriad i only know what they do and what they look like and thats about it
I may have told you wrong on 2 parts of the 2 white wires.. 1. The 2 white wires may share the same spade connector that plugs into the fuse block so may already be connected 2.the same 2 white wires draw there power from the fuse box and not from the dissy like i was thinking So my thought is still the same...but a differant path...PULL the 2 white wires off the fuse block and run a jumper wire from the 2 white wire spade connector to the positive side of the battery and then see if the pump works independently of the indicators It should run as its supposed to...if it dosnt and then we will know if the diode has failed or an issue is with one of the 3 components Diode, fuse box, or ignition switch My thinking is there is contact between the green wires and the white wires that share the same fuse and thats why the pump is operating in unison with the indicators If the new test arrangment still operates the pump in unison with the indicators then its the diode as there is still a path for that to happen, if the pump runs as its supposed to and independant of the indicators then the problem would be in the fuse block thats allowing the 2 white wires and the green wires to be making contact with each other thus creating your problem... i hope that makes The bottom line the power wire for the pump is making contact to the power wire after the indicator flasher and thats why tbe pump is working in unison with the indicators....what we are trying to figure out is where that connection is taking place The most obvious place is the fuse block, the diode and maybe the ignition switch(but not likely) I hope thats a little more understandable In fairness in full disclosure... im a little strung out on drugs at the moment HAHA. not that kind there legal perscription but im mildly high from the side effects and have been for the past 2 weeks and trying to get them and there quanty sorted. Hang in there Prop |
| 1 Paper |
| Simon,
jumping white to green would just eliminate the fuse box connections and fuse so only confirms them. You can test a diode with a multimeter, follow its instructions for for which way round to connect it, personally I find the cheap mini digital multimeters I had in more recent times to be sometimes unreliable in their readings possibly because of my very infrequent use of them. Have you tried Guy's suggestion yet? - >>If you remove fuse 3 (2nd from the top) this should leave the pump connected when the ignition is switched on, so it will tick, but should isolate it from all circuits other than the ignition. You could try this and see what happens.<< |
| Nigel Atkins |
| Tested the diode with multimeter - seems disappointingly fine. Nigel: I did try Guy's suggested test - if I remove fuse 3 the pump operates normally (as it does if I do not operate light switch, indicators or hazards). If I operate the light switch with fuse 3 removed the pump clicks in sympathy. Will try the bypass - as suggested by the drug-addled Prop - once I have the diode wired back in. Or would it still work without the diode? |
| Simon Fryer |
| Been researching the diode's role. It seems the diode prevents the power from the key buzzer from getting to, the light for the "fasten seat belts" and causing it to illuminate. Seeing as there are no door switches and the whole seat belt sensor mechanism is disconnected (always was) can this diode really be a suspect or even active? S |
| Simon Fryer |
| Simon, there is maybe a clue to follow in the photo that you posted a couple of days ago of the fuse box, combined with your Canadian location. ;-)
Your photo shows only a single white wire connection. UK cars would have two white wires connected to terminal 3 of the fusebox - either two wires crimped into one spade connector, or two white wires connected to the upper and lower blades of terminal 3. This is illustrated diagrammatically in the drawing that Nigel posted. As far as the circuits are they come to the same thing, fuse terminal 3 gets power from the ignition switch and connects to the fuel pump. Studying Haynes' wiring diagram (page 201 in my copy) the difference is that the N American cars appear much more complicated. They have a single white wire from terminal 3 which goes to a double-barrel bullet connector where it connects to the other two white wires, leaving one bullet socket vacant. So, why might this relevant? On the Haynes drawing there is a series of these bullet connectors all shown side by side (half way up the right hand side of the wiring diagram) This may be drawn for diagrammatic neatness, but if in real life those connectors are lying adjacent to one another, then alongside the fuel pump one with its 3 white wires there should be a similar one for the indicator wiring with 4 Green/Red wires. And just maybe one is connected into the wrong double bullet connector, or there is some other form of crossover at that point. I would try tracing the loom back to find where that bunch of bullet connectors are hidden. My guess is they are up behind the dash somewhere. Check the fuel pump connector only has the 3 whites that it is supposed to have! |
| GuyW |
| On it! |
| Simon Fryer |
| A briefer message than mine! Good luck! |
| GuyW |
| I'm with Graeme Williams on this; My understanding is that the pump is working ok with the ignition on, and that with the ignition on when lights or flasher etc are operated the pump ticks in sympathy. It does seem to me that the voltage at the pump is just at the threshold where it will operate, and the voltage drop caused by any other load (eg the lights) is enough for the pump to drop out. I think you need to check the voltage at the pump, both with and without the lights on..... Jim |
| J Smith |
| Found the connectors - all looks as it should :( |
| Simon Fryer |
| Pity! Worth checking though. |
| GuyW |
| I'd say still a good spot, of single white wire, by Guy certainly one I missed and worth the checking of connections.
I had a look at the diagrams from the Driver's Handbook on the DVD I've got but it's such a clunky system that was the very little knowledge I have and poor eyesight it was too difficult for me to follow. I don't know if the Canadian and NAS diagrams vary at all but there were on offer 1970-71 and 1971-2., Haynes ties up chassis numbers but not the DH (as they were less relevant at time of publication). Working from the pump back seems a good idea particularly now, personally I'd still check it's earth, run a wire from it's earth connection back to the earth on the battery, even perhaps also a live from battery to confirm full power to pump. To be fair, Prop may not be drug addled (at least not always, if at all?) but types on to one of these absolutely marvelous mobile devices that are, and will be, the savoir of us all (or not). |
| Nigel Atkins |
| Can you try another known good condition battery ? R. |
| richard b |
| Will charge battery again, see what kind of shape it's in and see if it makes a difference. |
| Simon Fryer |
| Simons car is December 1971...so its actually a 1972 model
and on page 205 of haynes..the 1st USA midget to come with an alt and not the generator I dont think its the low energy battry effecting the pump. if he has headlights, hazords, turn indicators,all 4 side markers and a horn....then id think the battry has plenty of juice to still power the pump properly I missed the single white wire that Guy found on the fuse block... THAT really stands out HUGE in my book IM NOW Thinking... the single white wire is powering the ignition ONLY and NOT the fuel pump. The fuel pump is being feed from a differsnt source most likly off the turn signal indicator power wire in the boot of the car on the same side as the pump. Prop |
| 1 Paper |
| That is true nigel, i use my (to samll) smartphone for everything sadly spell check dosnt work on my phone for the BBS, and have not been able to resolve the issue
But yes... i am somewhat high on drugs..haha I got diagnoised with type 2 diabetes several weeks back and its been hell trying to sort my new meds out, and they all have side effects...mainly lowering my blood sugar to MUCH and crashing me which is like being stoned or sending my suger sky high and making me fell high as a kite and invinciable... but all are effecting my mental state. Working on drug try #6 at the moment...im feeling better after 18 hours of sleep that just sort of happened when i went to bed last night and didnt set the alarm for Ah ...life, what can you do? Prop |
| 1 Paper |
| Pump has a white wire running off it that, according to the wiring diagram, runs forward to the junction noted by Guy. Here it meets the white wire from the fuse block and the white wire going to the ignition switch.
I don't recall anything unusual with the rear indicator wiring. Green wire out of light junctions into LGW and joins group of junctions (again noted by Guy) to link up with front indicator. I'll have a dig around in the boot/ trunk and see if there's anything suspicious down there. When it's not dark and/or freezing... |
| Simon Fryer |
| Much sympathy Prop: I was diagnosed Type 1 8 years ago (age 49!). |
| Simon Fryer |
| The correct path for the white wires starting at the fuse box should be
2 white wires...1 goes directly to the fuel pump the 2nd white wire goes to the ignition switch From the ignition switch a 3rd white wire goes to the tackometer Simion....as guy pointed out from your photo, you only have ONE 1 white wire comming off your fuse box, NOT 2 Meaning your single white wire that is connected to the fuse box is ither powering the ignition switch OR its powering the fuel pump, but NOT both So ither the ignition switch is getting juice from a differsnt location or the fuel pump is being feed from some place else Thus my therory is the fuel pump is being feed off the turn signal indictor power wire as that wire is the closet to the pump znd most easily accessable AND the pump is ticking in sync to the turn signal indicators Then agiqn, im still a bit high....haha Thanks for the kind thoughts ... i still cant understand how thst happened to me....old age i guess Prop |
| 1 Paper |
| Prop, I think that the white wiring is correct. The single white at the fusebox is as Simon's version should be as the junction into two wires is remote from the fusebox blade.
The white at the fusebox isn't supplying the pump and the tachometer, it is the other way around - it is an ignition switched supply TO the fusebox. It then goes via fuse 3 to supply the panel lights, stop light wiper motor and hazard warning lamps. You could disconnect that white from the fusebox and the pump would still run. I had thought this might be feeding back from the hazard switch and fuse into the pump circuit. Or that one of those supplied might be drawing too much current and starving the pump, which is why I suggested removing that fuse to see what happens. Simon tried that, and it made no difference. |
| GuyW |
| Simon, is the synchronised switching the same whether the engine is running or not? Or are you just testing it with ignition on and the engine not started? You could check voltage across the battery terminals when the engine is running. |
| GuyW |
| Guy... you have me there But the bottom line is ....as you pointed out, simon only has 1 white wire at the fuse box, not 2 ...where is the 2nd white wire ? Prop |
| 1 Paper |
| The one white wire goes into the loom and then to a double bullet connection, which has wires to the pump and the tach. Simon has checked that. |
| GuyW |
| I don't think I fully appreciate what the issue is? The pump works with the ignition on; The pump doesn't work with the ignition off; With the ignition on, turning on the lights or indicators causes the pump (which is already powered up) to click. Surely this must mean that the power to the pump is being reduced when the lights etc are turned on? |
| J Smith |
| I too have been trying to understand the problem. Surely the pump only clicks when fuel pressure in it gets low? |
| Bill Bretherton |
| Guy,
Simon previously replied to me that he was reluctant to start the car with the present fault. I was wondering about getting more electric power from the engine running and whether the alternator would have any involvement. I also wondered about disconnecting the existing wiring to the pump and running earthing and live supply direct from the battery to hear how the pump runs from the battery and then turn on the indicators and sidelights to see if the situation is the same. This might point to how much the wiring to the pump is contributing to the situation. |
| Nigel Atkins |
| OFF-TOPIC
Prop, wow what a challenge you must set the scientists of your country, to introduce chemicals to interact with your body's natural chemicals. The possibilities of good and harm to society with how this could affect your mind are endless at both extremes - I think you will probably become even more of a genius than you are now! Being serious amending your diet (well as much as you can with the particularly messed about food of your country, not that we're much better over here) and your habits could help you and help to reduce the drugs you take, it helped my friend. |
| Nigel Atkins |
| Simon.
Having reviewed the thread and applied some logical thought, it seems you may have hinted at the problem on 25th October:- "Could it be a ground fault somewhere in the column/dash area? " I think it could be a ground fault, but in the boot/trunk area, rather than the column/dash. IIRC the earth/ground for the rear end of the car is in the middle of the back panel, possibly on one of the licence plate bolts. If that earth tag is not making good contact and you have a high resistance, the various circuits will be trying to earth through each other. Your sidelights, indicators and fuel pump will all be trying to earth through that point. Check and clean it and see what happens. |
| Dave O'Neill 2 |
| Thanks Nigel, l had missed that about the engine not being started up. My comments about the white wiring were to eliminate thoughts being raised about the diode and to check that hidden bullet connector.
If this is all being tested without the engine running then l am not at all convinced that there is any sort of problem at all! It would depend on the age and conditions of the battery. If it isn't in top rate condition then testing without input from a charging generator is very likely to cause the lights and/or indicators to draw too much current and starve the pump. The pump ticking in time to the indicators is just an amusing incidental side effect. Even then, as Bill points out the pump should only pulse if the pressure on the carb side drops even if the electrical supply is in effect being switched off and on. The other possibility is that the inlet pipe to the pump is leaking in air. Maybe the fuel level in the tank is very low, or even non existent following a rebuild? |
| GuyW |
| Picking up on what I mentioned a while back and what J Smith is also saying, turning on the lights or indicators drops the voltage to the pump, the diaphragm pulls back and goes "click". Check the voltage on the pump as you turn on the lights. |
| Graeme Williams |
| Yes, l agree. A single click is very likely and if this is when the engine isn't running the voltage drop to the pump is not at all surprising. l don't think it necessarily even represents a fault. What is less likely is the repeated clicking in time with the indicators, unless this is accompanied by low fuel pressure or low fuel tank. |
| GuyW |
| I think all the suggestions raised have been good and point towards a/the possible problem(s) (there could be more than one problem contributing to the overall problem) and the possible lack of a problem (other than perhaps battery condition and/or battery connections).
Dave has raised a good obvious but until then overlooked/forgotten point, as the obvious can often missed especially when dealing remote secondhand. How about a wire direct from battery earth to the shared earth point to eliminate/reduce this possibility. I think with these problems it pays to start at one end and work back (or forward as the case may be), as the car is being recommissioned it pays even more so that usual to check and double check everything. With any electrical fault finding, especially as I know so little about electrics, I always like to start with a battery in good condition, fully charged and with good clean and secure connections as this helps with the fault finding instead of possibly hindering or even inflating the problem. |
| Nigel Atkins |
| Well thanks everybody - much to consider here. I will begin as follows: Charge battery and assess condition Review earths in trunk area and underneath(pump has its own separate earthpoint on the body). Start engine and explore effect. Run auxiliary earth from pump to battery. Run auxiliary power feed from battery to pump. Did I miss anything? If this turns out to be an incidental side effect, it will be a while before I find it amusing... |
| Simon Fryer |
| If it were me, the first thing I would do would be to measure the voltage at the battery terminals with the ignition and lights on. (engine not running) If it is much below 12 Volts I would suspect the battery is faulty/flat.
If battery voltage is OK grovel underneath and measure the voltage between the pump power terminal and the pump casing, first with the ignition on, then with the ignition and lights on, and see if there is much difference between the 2 readings. If the reading is much below 12 volts, check if there is a voltage difference between the pump casing and the metalwork of the car. It should be very low, I would guess less than 1 volt. Jim |
| J Smith |
| Simon, if things aren't sorted then when you run auxiliary earth and power feed from pump to battery have the original connections disconnected. I'd also try the earth from battery to common earths point at the rear as that might also highlight possible poor earths to the rear of the car. Good luck. |
| Nigel Atkins |
| For the love of god... the car hasnt been started yet...i thought it was running I dont understwnd how your able to test as the residual pressure in the fuel system can last seversl hours even days so there wont be much ticing from the fuel pump until its started There must be other issues with the pump Lets get the car started 1st and then see what happens Gez... 68 threads later and just now learning the car hasnt even started yet. WOW ! PROP |
| 1 Paper |
| The bottom line still remains ... The fuse box only has 1 white wire... NOT 2 as it should have came from the factory Once the car is started...thats where we need to begin Why and how was the car moded by the privious owner to have only 1 white wire What happened to the 2nd white wire on the fuse box its not there in the photo Prop |
| 1 Paper |
| Prop, again. One wire from terminal 3 is correct for Simon's car. The wire divides into 2 further up the loom at a double bullet connector.This isn't a modification, its how it came from the factory. Your car may be different. |
| GuyW |
| Prop, your previous but one post made me laugh, proper Prop, but Simon did put earlier that he was reluctant to start the car. The drugs seem to be kicking in then falling out. |
| Nigel Atkins |
| Quote Simon: "Did I miss anything?" Yes, check the bl**dy voltage on the pump terminal before you worry about earths, extra wires, fuses and so on. Will take about 5 mins and provide useful information if not a direct answer. |
| Graeme Williams |
| Whooo, Graeme get the Prop pills out. :)
Simon may not have a multimeter and if my experience is anything to go by cheap modern digital mini multimeters aren't to be relied on so you need to find a reliable (probably old) analogue or an expensive reliable digital that might be too complicated to understand at the moment anyway. A bulb in the wire may give as much info anyway, see how bright it is when directly connect to both sides of the battery then connect instead of pump and see what difference there is to brightness and then with with indicators and sidelights on. Simon you always need to test the test equipment before every test to confirm it's working properly be it wire, bulb, fuse, multimeter and certainly Large Hadron Collider. |
| Nigel Atkins |
| >>>>>Simon may not have a multimeter He did imply in his posting at 20:57 on the 27th that he has a multimeter - though not an expert at using it. He did manage later to test the diode with it though..... Jim |
| J Smith |
| Ah, now Jim, I'd forgotten that, and advising on the diode test - not that you can trust these cheap digital mini multimeters ;)
- but - even so the facts should never spoil a good wind-up between Graeme and I. :) (plus I'm old and did forget) Just looking at the Instruction Manual on mine and it has - >>Accuracy is specified for a period of a year after calibration (which I remember) and at 18C to 28C (64F to 82F) with relative humidity to 75%.<< (which I forget) so I wonder if Simon's is reliable at 36F. |
| Nigel Atkins |
| Maybe it's time to get the sled dogs ready and get my sled out for a 1000 mile trek across the frozen tundra facing wolves, woods, polar bears and hostile natives to help out. On the other hand, I think I'll stay right where I am at the trading post. (lol) (If I was a lot closer, I'd go and see what I could do.) Clare |
| Clare Ravenwood |
Revised action list: Test the test equipment Charge battery and assess condition check bl**dy voltage on pump terminal Review earths in trunk area and underneath(pump has its own separate earthpoint on the body). Start engine and explore effect. Run auxiliary earth from pump to battery. Run auxiliary power feed from battery to pump. Confirm order of Large Hadron Collider If only it were still 36F I think you'd find the natives quite friendly Clare |
| Simon Fryer |
| No...for the 1972 midget USA spec page 205 of the haynes manual ... the 1st USA Midget ... clearly shows the fuse block with 2 white wires...not one. See for yourself Prop  |
| 1 Paper |
| Look at the very top middle of the page...you can see the fuse box....there are 2 white wires coming out of the fuse box Simons car was built in december 1971...with an alt not a gen.... this a 1972 midget spec Prop |
| 1 Paper |
| Simon,
well done you've got the flavour of some of the intercourse here. Don't bother with anything - Large Hadron Collider - "It should NOT EXIST’ Hadron Collider scientists fear universe could DIE at any moment" - taken from one of our less reliable news publications. Back to your car, having got some books out Prop might have a good point *if* your alternator has two brown/yellow wires coming off it and not just one. Confusing isn't it, so many publications but which is right and by how much. If you've got the correct (Canadian) Driver's Handbook for your car the wiring diagram in it may be more relevant, failing that Diagram 10 in the factory Workshop Manual AKD 4021 (12th Edition) may help, subject to wiring being original and diagram correct. I've no idea how much Canadian cars varied from North American cars but some points that might be relevant, particularly change of indicator stalk and lighting switch, from Terry Horler's book Original Sprite & Midget The Restorer’s Guide – http://www.amazon.co.uk/gp/product/1906133336 . GAN5-112276 (Dec 71) North American cars: changed hazard warning switch, new seat belt warning system with gearbox inhibitor switch and warning light set in radio console. . GAN5-113000 (Dec 71) Different indicator stalk control and lighting switch for North American cars. . GAN5-113617 (Jan 72) Different reversing lights for North America. |
| Nigel Atkins |
| Even if the flasher feed was somehow linked to the pump feed it shouldn't make any difference because AIUI the "clicking" of the pump only happens when its contacts have closed i.e. because the fuel pressure has fallen so there is demand. The pump doesn't care where its 12v feed comes from as long as it is present. I'm still wondering if there IS a problem. |
| Bill Bretherton |
| Bill you may be right that there isn't a problem or as Guy suggested that it's fuel rather than electric related but if you're recommissioning the car and not able to compare it with another and lack the vast experience and knowledge of some posters on here (not me) then you'd want to find out for certain so that you can rest your mind and not encounter further and worse problems from it later. |
| Nigel Atkins |
| Bill...you could well be correct...i had thought the same but simion was insistant that. The pump with ticing in tandum....
But that said...i didnt realize the car had never been started yet.... it wss just ticing off the key which makes this situation now theoretical over practical. I dont have much of a leg to stand on as nigel has pointed out there are some north american cars that are a breed unto them selves and this could well be the case this car was not born with 2 white wires at the fuse box. If thats the case....the past 82 postings have all been for nought and a waste Really we need to find the correct wiring schmatic that fits this odd duck midget 2. Get the battrey charged up 3. get the car fired up and running and see what we got 4. THEN IF there is a problem (???) repeat the whole process we just went thru....my guess is there will be an issue but not electrical its going to be a leak ither internal or external, cuz once the pump pressurises it tends to hold thst pressure for a long time until its ran off...and it appeared thst simion was doing continuios testing appeartly without any pressure build up as near as i can tell between the pump and the carbs Prop |
| 1 Paper |
| I'm working with Diagram 10 in the factory Workshop Manual - it appears to match my car perfectly (VIN no. & wiring, equipment etc.)
The car has been started in the past (year ago?) but then this problem arrived (with the restoration of lights and other electrical business) and there was talk of electrical fires. Nigel has my situation in a nutshell: Bill you may be right that there isn't a problem or as Guy suggested that it's fuel rather than electric related but if you're recommissioning the car and not able to compare it with another and lack the vast experience and knowledge of some posters on here (not me) then you'd want to find out for certain so that you can rest your mind and not encounter further and worse problems from it later. Thanks everyone. |
| Simon Fryer |
| Prop, as the car's over 45 years old and the wiring has had at least some amending it might be that there isn't a wring diagram to fully match. Simon is concerned about damaging his car so is being a bit more cautious than you, he has less experience than you ... (inset your own thoughts/words here). :) I don't blame you but do caution you about putting all your faith in Haynes when you know full well there's only the relevant Driver's Handbook worthy of such trust. ;) |
| Nigel Atkins |
| Sorry Simon I missed your last post. If your car is Diagram 10 then that's a good basis to work from.
I wondered if perhaps a different/previous switch might be on your car with regard to >>GAN5-113000 (Dec 71) Different indicator stalk control and lighting switch for North American cars.<< do all the wires have the correct colours from the connections, sometimes people put old connectors on to replacement stalk wires and it isn't always easy to see, check the wires correspond either side if only to tick another thing off. |
| Nigel Atkins |
| Prop, my apologies if the wiring diagram you posted turns ou to be the correct one. But either way, Simon's car is wired with a single white to termnal 3, not 2, as was correct for a 1971 car. And those cars with a single white simply split the supply at the next bullet connector into two, so it comes to exactly the same arrangement.
I also didn't mean that it is a fuel related problem as such. Low fuel in the tank or low fuel presure on the delivery side could be an explanation as to why the pump clicks repeatedly with the indicators, as otherwise one might expect a single click after which, however often the voltage varied the pressure in the fuel line would hold the pump from cliking again. I do think that if this clicking syndrome is occuring without the engine running and without certain knowledge that the battery is fully fit and charged, then it is likely that there is no problem at all with the fuel pump and its wiring. Get the battery and / or the charging circuits operating correctly and then redo the checks. You may find that all is well. "Fools and bairnes" |
| GuyW |
| Being we are all kissing and making up...im still playing the part drug addict...haha
Im on a short fuse latly, ive found im more intellegwnt thwn the medical staff im working with, there just idiots and this type 2 and getting it sorted has gotten long in the tooth and having to deal with the side effects of the various drugs these idiots are expermenting on me with is daunting...some of these drugs are ruff ... who ever thought insulin is just good ol fashioned insulin were idiots So im pretty messed up at the moment and have been...i hope all will understand if i came across as maliced ... ( well hell i meant it..haha) i do respect and charish your friendship and it was never personal ...im just tired to much crap in my life and not enough tolit paper to deal with it all Prop |
| 1 Paper |
| Simon
If its your wiring you lack confidance in... and i totally get that, as mine is a mine field of adventurious fire wanting to escape. Then follow my lead and get a battry isolator switch, and place just ahead of the battry and the rest of the car on the pos side, they have a big red key and cost around $10 to $20, this way you can shut the entire car off and on in a fraction of a second But honestly... if everything is working with in reason i dont think your going to have an issue... you hqve already been applying the key to the electric for seversl hours over tike and nothing yet flamed on If anything keepnthe battry cable loose so it can be easily be pulled free fromnthe exploding inferno Keep a few cans of un opened coke a cola close by in case of fire maaybe some baking soda if it does flame on a good hard shake of the soda pop and open at the fire and it will knock it straight down Bottom line ... you are going to have to fire this diseased animal up to really find out what if any issue there are Which both Guy and I are probably thinking there (could ??) Be due to the fact you were able to grind on the fuel pump continuosly and the presurre never maxed out and kept on grinding But im leaning no electrical issues... i would clean the ground contact on the fuel pump as just a good measure for a once a year maintance prevention cuz they do get dirty and muddy and then start to rust ...sonits worth the extra 5 minutes in preventive maintance Prop |
| 1 Paper |
| Simon,
now I'm able to master counting the first three letters of the alphabet I might be able to help you. If your car's chassis number is GAN5-U-C 112*** (or 113***) then you can get a Driver's Handbook for it that will help you to know about the car, servicing, driving and with possible future issues. The period Driver's Handbook would probably be Publication Part No. AKD 7937 or you can get a reprint that covers '67-'72 cars as per this link - http://brooklandsbooks.co.uk/index.php?route=product/product&path=12_138_631&product_id=561 ETA: link don't work for me so details here - . Pub. 1971. (US Edition). Covers the years 1967-1972, general maintenance, instruments, etc of the GAN 4 & 5. 64 pages. Illustrated with drawings. AKD788. SB. SKU: MG64HH ISBN: 9781855206311 ETA2: link works if you copy & paste For some reason I thought Canadian cars had their own books. If your car isn't a GAN5-U-C then, er, I don't know. |
| Nigel Atkins |
| Sample of what they contain, including wiring diagrams, note this isn't the one for your model(s) With it you'll know more than many other, even long term, owners -  |
| Nigel Atkins |
| Have you tried disconnecting the fuel pump to see if it really was ticking with the indicators? - just a thought. |
| M J Chapman |
| Today's done list:
Charge battery and assess condition Battery fully charged and reading 12.5V on my handy multimeter check bl**dy voltage on pump terminal - 11.9V at pump ignition on/no lights - indicators on - rhythmic small voltage drops synchronised with indicator flashes Cleaned up pump earth (again) and reattached. BTW PO fitted a Moprod pump with a self-fabricated aluminium bracket. It was all working fine when I took the car apart though. Nigel: thanks for the tip re the Manual. Mine is a GAN5UC113 and I have the Robert Bentley reprint which is where I'm finding the wiring diag. Is the manual you suggest substantially different to this? Mr. Chapman: I've double/triple checked the behaviour of the pump - it blips in synch with the indicators and hazards, as well as when I operate the light switch. |
| Simon Fryer |
| Simon, If it's synchronised with other loads coming on that would seem to indicate a sensitivity in either the pump electronics or the other loads coming on reducing the feed to your pump. |
| David Billington |
| David: how would I address these possible scenarios? |
| Simon Fryer |
| >>>how would I address these possible scenarios? You could start the engine and see if it still has the symptoms; with the alternator charging, the battery voltage should be higher and quite likely above the voltage sensitivity that your pump seems to be showing. Jim |
| J Smith |
| Okay ... so i looked up Moped fuel pump Its a knock off of the SU fuel pump for the MGB...its got mixed reviews and seems to last about 5 years on avg but has a nasty reputation of its case cracking and its reed valve gloing bad The good news it dosnt have points Its solid state electronic. The belgian company was purchased by hazel quitnon around 2005 and became ecco fuel pumps . |
| 1 Paper |
| Simon ... i think your going to have to start the car...there is nothing else that can be discussed until its running
Considering this pump is electronic and not points, im not sure what your hearing...the good news is it wont catch fire at this point...if it where going to catch fire it wohld have done it kn the 1st turn of the key At least now we know why your able to get it to run full time, instead a of a few ticks and then have it fully pressurised So yeah... fire it up, nothing can be said beyond where we are at. Prop |
| 1 Paper |
| Hi Simon,
what I'm strongly recommending (as always) is the Driver's Handbook (or reprint) which would now be called the Owners Manual, the user's instruction book if you like, it's the one you get with the car when it was new, it has loads of useful info for you. It's not a repair manual although it will help with many repairs because of all the information in it and it's not a workshop manual but does contain servicing and maintenance instructions and schedules. If you get a copy and read it and use it and refer to it you will know and learn more about your car than many other owners know about their cars even many long term owners. Allowing for the weather temperature and how accurate or not your handy multimeter is 12.5v on your battery is about full (see below) but how long does the battery hold and regain that especially after putting heavy loads on it especially starting the car. Do another battery voltage check before you start the car to see if there's any drop, you don't want a battery that's not in good condition and good charge when you have electrical problems to find and starting the car in the cold, it could hinder progress especially if you have to keep restarting the car. Battery Voltage and State of Charge: 12.66v . . . . . . . . . . 100% 12.45v . . . . . . . . . . 75% 12.24v . . . . . . . . . . 50% 12.06v . . . . . . . . . . 25% 11.89v . . . . . . . . . . 0% (NOTE: these readings are at 80 degrees F. Battery voltage readings will drop with temperature roughly 0.01 volts for every 10 degrees F.) (At 30 degrees F. a fully charged battery will measure about 12.588 volts, and at zero degrees F it will measure about 12.516 volts.) from - http://www.aa1car.com/library/2003/us20310.htm |
| Nigel Atkins |
| I was wondering about the 12.5v at battery down to 11.9v at the pump with just the ignition on, is this an acceptable loss for model of car, assuming battery voltage hasn't dropped between taking battery and pump readings and only standard load for model with ignition on? |
| Nigel Atkins |
| Thanks for your time researching the pump Prop. It's definitely way over five years old but seems to be in good visible shape (no cracks). Start the engine is next step. Nigel: thank you - I will follow up on the Driver's Handbook. I'll also be aware of the temperature's effect on battery strength. 30F or so right now with 6 inches of snow... |
| Simon Fryer |
| Simon, right at the start you said: << It blips on each flash of the indicators and each on/off of the sidelight switch>> Clearly, for the indicators to work the key needs to be switched on to "ignition", so the pump is also powered on. But do you mean that the pump also clicks when you just switch the sidelights on, without the ignition being switched on? |
| GuyW |
| Guy, Right back near the beginning of this thread Simon said this: "this issue is only present with ignition on." This is why I am thinking that there isn't a problem apart from perhaps being a dodgy battery.... Jim |
| J Smith |
| Ah yes, a few messages further on! I missed that. I agree with you Jim. In fact I think there is probably nothing wrong with it! Repeated clicking does suggest all of this is being "tested" whilst the fuel level is low, or the carb is overflowing. All are the sort of minor issues which are best checked and corrected through after it has been started up! |
| GuyW |
| I suspect this is 106 posts about nothing actually wrong. |
| Graeme Williams |
| But if it leads to the purchase of a relevant Driver's Handbook then it's for everything right. :) And things have been learnt along the way and Prop has had a moment of glory in with his usual style of happy(?) posts. |
| Nigel Atkins |
| Nigel, Do you by any chance own stock in the company that publishes the Drivers Handbook? ;-) |
| Martin |
| OK - no start. Spark at the plugs and full float bowls but won't even catch. Battery down to 11.8V when I began today so I'm going to go with the running theme of this exchange and buy a new one. Question is whether to do it now or wait for spring... Pump ticks about once every 4 or 5 seconds with ignition on which suggests something is amiss I think? Don't see any leaks. Nigel: this is what I'm working from (see pic). I have Haynes but haven't found it to be very clear.  |
| Simon Fryer |
| No start - when did this thing last run? If recently, what has been apart since, if longer then check for assembly problems, i.e. timing correct and not 180 deg out, plug leads in the right order. If you suspect carbs try a splash of fuel directly down the intakes, it should at least cough. Make sure choke linkages and carb pistons move as they should. I've just discovered that mine runs a whole lot better when it has fuel in both carbs (stuck float needle valve) |
| AdrianR |
| Martin, no shares or royalties just spreading the word. |
| Nigel Atkins |
| >>>>Pump ticks about once every 4 or 5 seconds with ignition on which suggests something is amiss I think?
It is quite possible that the battery voltage is only just above the threshold for the electronic pump to actuate, then because of the pump's load the voltage is dropping, causing the pump to de-actuate again which is what is causing it to click too frequently. Operating the lights or flashers is simply causing even more load on the battery. I wouldn't do anything else until you have replaced the battery - even if you can 'borrow' one from somewhere else? Jim |
| J Smith |
| Simon,
car batteries are one of the most oversold items on a car and I don't like to see them replaced unnecessarily but if you fully recharged only the other day and (if) it was in reasonable condition then it should take a fair bit to completely flatten it, I think you should replace it ASAP to get your car at least started ASAP. A good battery should survive many winters so get it now. I don't know about Bentley but - "The Driver's Handbook at the beginning of this manual is similar to the handbook that was provided with every new 1275 cc Sprite and Midget." so if it has the same stuff that's on the Contents page I put up in an earlier post (plus US emissions stuff) with such things as how to operate the choke, the heater, fold the hood, tyre pressures, etc. then it's another "similar" version. Personally I don't like Haynes and I've got 1974 and 1980 versions and neither of them fully cover my 1973 car and have errors and omissions, I always use them in conjunction with other publications. In the UK battery faults are the major causes of car breakdowns but in reality very rarely is it the battery that's the cause, it's the owner or driver that caused the battery to fail. http://www.theaa.com/breakdown-cover/advice/top-ten-breakdown-causes |
| Nigel Atkins |
| Simon,
sorry my last post about the Bentley book wasn't very good, if it contains the Driver's Handbook and Workshop Manual then that should be a very good book indeed. I thought, probably mistakenly, that the only Bentley book I'd seen was as US version of Haynes. I've seen posters here mention their copies of Bentley but this is the first time I've seen mention, or in your case photo, that it also has a Driver's Handbook section. So thank you for for teaching me that, I was previously wrong which just goes to show even the very best, er, well, mildly mediocre in my case, of us can make mistakes. |
| Nigel Atkins |
| It dosnt run....hmmmm
Check the spark plug wires are set up as 1342 Replace the battery and fuel if older then a year as fuel goes bad fast. and batterys solidify if not used Make sure it has fuel and not evoporated out of the tank Check the float needles are not stuck/sticking, Also the pump can be cracked enough that it allows air to be sucked in but not let fuel out Use a couple blast of starter spray to get it to pop to life If it only runs a few secounds off the starter spray, and has fuel,+ pressure and plug wires are at 1342...then sure sign of sticking float needles Prop |
| 1 Paper |
| Adrian: car last ran June 18th this year. Currently have fuel in both float chambers and no changes to settings since. Nigel: thank you for allowing me to contribute something useful to this thread - I feel guilt at the otherwise one-sided nature of it. Prop: will replace battery and check fuel (there seemed to be plenty of it when I disconnected the pump. I do understand that contemporary fuels degrade quickly. We're firmly into minus temps now so it's getting to be a struggle out there. |
| Simon Fryer |
| Simon, since it ran, have you had the head and manifolds off?
Sometimes cars that have been stripped and dried out in this way are reluctant to start. I think it is because of the absence of any trace of atomised fuel in the inlet tract, and spinning the engine on the starter, especially if the battery is a bit down and the engine a bit tight, doesn't generate sufficient air flow speed across the inlet jet to atomise the fuel. It's why in these situations a car will often start when towed, but not on the starter. Use of a 'damp start" aerosol as Prop suggests should work, or even directing gas from a propane torch (unlit of course!) for a few seconds into the carb (throttle butterfly wide open) will also do the trick. Once it has fired up the gas velocity will be enough to draw in and atomise the fuel to keep it running. Splashing neat liquid petrol directly into the carbs is likely to flood the engine and not be helpful. It needs atomised fuel in vapour form. |
| GuyW |
| Simon: Try googling the particular manual you want. There are downloads out there. |
| Graeme Williams |
| Ok, so it hasn't been apart, has spark and fuel at least as far as float chambers. It's still possible for carbs to stick (mine did), so have you checked that the jets move down on choke and the pistons move freely up and down? With the airbox removed, after a few starting attempts you should see wet fuel in the intake. @Guy, yes you are right but I still find the "splash and cough method" motivating and at least tells you you have some ignition! |
| AdrianR |
| You may well be right Adrian, at least to get a cough out of it! I prefer the propane cylinder gas blowlamp as its cleaner and easier to direct the gas down the carb throat. Assuming, of course that one has such a thing! (gas blowlamp, I mean, not a throat!) |
| GuyW |
| See what happens after a new good quality battery is fitted, even if it doesn't start the car it'll probably get it a lot nearer to starting. |
| Nigel Atkins |
| If the pump is flooding the carbs that should be very evident from the overflows on top or weeping around the gasket. Some pumps are intended to run continously by design. Not got one of those? |
| Graeme Williams |
| Im with guy and adrian. Its most likly something sticky in the carbs My money is on the float neddles sticking inside the lid of the float bowl chamber under the floats Its not beeen sitting to long, id say. Throw a gal of fresh gas on top of whats in the tank Take the fuel line off the carbs and see if you get a good blast of fhel.. if so, its got to be sticking needles in the float Use guys propane or my starter spray to get it to pop |
| 1 Paper |
| What the lattest simon Its 27 degress this morning... you could have kept the chill to yourselves...haha Prop |
| 1 Paper |
| Thanks for checking in Prop and to everyone for your knowledgeable contributions to this fascinating thread.
I can't get the engine to fire. Battery definitely dud and choke mechanism was seized up. Put some effort in to the choke but still no go. Basically it's just too cold - no fun out there and nothing works readily (especially me). Also, the people who pay me seem to prefer that I do stuff for them from time to time so I've opted to call it for the season and attack with renewed vigour in the spring. I'll be in touch once I get somewhere and in the meantime, Happy Thanksgiving, Christmas, Hannukah, Easter etc. to all. Simon |
| Simon Fryer |
| Simon, get a new battery *before* resuming in spring and you'll stand more chance of the car starting with renewed vigour too. :) Enjoy your break as the car will steal your time later. |
| Nigel Atkins |
| Come on simon, dont do that, build a rocket stove to keep warm see YouTube your almost there, we are all here for you...surely the MAN lets you have lunch hour a couple times a week We are all invested into your project...besided we live for this stuff, getting dud engines to fire is what we enjoy alot in life Let's get it fired up before the holidays what better gift is there then that to yourself. Prop |
| 1 Paper |
| As I recall
You have spark, there is fuel in the floats, it did run at one point recently (july) and the battery maybe a little tired and long in the tooth Does the engine crank and turn over recently? Did you try guys propane trick or spray can starter spray...what happened? Btw.. to crank the engine from the engine bay is easy ... remove the small red/white wire off the seliniod and make a jumper wire with a connector to fit on the place of the red/white wire connection of the selinoid and use the other end to of the wire to flash the positive side of the battry... Make sure the car is in nutral, to start the car or excite the ignition system put the key in and turn to the on position or leave the key out to simply rotate the engine without starting the car Doing that you can fiddle with the carbs while cranking the engine Let us know what happens Prop |
| 1 Paper |
| Really appreciate your enthusiasm, and hate to keep you in suspense Prop, but I'm done for this season. I can crank the engine from the engine bay using the button on the solenoid but my finger goes numb in about 3 seconds. Just think how much fun we're all going to have when the thread resumes in spring! S |
| Simon Fryer |
| So, as it turns out, we're experiencing unusually non-freezing temps right now giving me new opportunity. Bought and installed new battery. Engine started after some swift blows to the float bowl tops stopped the flooding. However, weirdness remains: pump syncs with flashers and side/headlight switch. S |
| Simon Fryer |
| Simon, Usually when seemingly unrelated electric components start affecting one another, the problem is with the grounds. For some reason, one will borrow the ground from another, but will compromise the operation. I suggest going through it and try cleaning the grounds for the various components and see if that helps. If you have already done this, sorry, I forgot. I didn't want to review all the posts again. Charley |
| C R Huff |
| Start with the attachment point of the negative lead from battery to the car bodywork. Its easy to check the battery terminals and forget about the other end of the lead! If this is corroded, none of the others will work fully. |
| GuyW |
| Yeap start at the (earth) battery post and work forward - post to clamp, clamp to wire, wire to its connections and insulation, wire to first earth connection from battery earth lead to body - your hip bone's connected to your thigh bone, etc.. |
| Nigel Atkins |
This thread was discussed between 22/10/2017 and 25/11/2017
MG Midget and Sprite Technical index
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