MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG TD TF 1500 - TD quit this morning

Well, at 5:30ayem this morning, pulled the TD out of the garage for the 11 mile trip to the office. Dark outside at around 50 F.

Ran okay for a coupla blocks but noticed the ammeter (still not sure if it works right) was showing a lot more discharge than normal with the headlights on.

Used the turn signal at the stop sign and noticed it was going really slow. Pulled up the hill from the stop sign and it started sputtering and slowing and...it stopped. Would crank up and quit. Several times like it was running the gas out of the carb bowls.

Backed down the hill into a gas station. Let it sit and same thing but then it cranked and stayed running at about 3000rpm with the choke out. Made it home but must tend to it this evening.

Any ideas? About 4000 miles on the plugs. Gas dipstick registered 4 gallons. Quick flashlight check under the hood showed nothing loose or broken. Checked it running with headlights off and ammeter still showing discharge and did not show charging at any rpm...

dave lackey

it is possible you have mutiple problems, but this is USUALLY not the case. if she has enough juice to crank and fire she has enough juice to continue to run for a while...assuming your ignition components are up to snuff. what were the weather conditions...if the air was really damp you could have moisture problems...ignition leads, distributor cap, coil lead, etc. you could use a moisture displacing agent like "force 5" sold at auto parts stores. did it run fine later in the day? (that would point toward a moisture problem) how do the points look? good gap? no pitting? if you turn the engine over with a plug wire off do you get a nice blue spark to jump? an old mechanic once told me "...90% of carburetor problems are in the ignition..." if carbs are initially set up correctly they basically keep metering right along. they don't usually develop "sudden problems". any previous indications? updates posted here would be appreciated. they would help you and the rest of us to learn more about these wonderful old cars. regards, tom
tm peterson

Didn't have time or daylight to check the distributor, etc. Wires were all hooked up. Car spent the last four days in the garage. No moisture there...

Wondering if the generator is the problem. The warning light shows a dim red even while driving. Battery is 3 years old. Blinker was VERY slow. Ammeter showed discharge even with no lights on at 3000 rpm....

Arrrgghh.
dave lackey

But, then again, could it be the plugs? Haven't pulled them but only in the last couple of weeks have I had to use the choke because of "cold" weather. I do recall it taking about four or five tries to crank this morning when usually it cranks right up on first pull or the second...

dave lackey

Sounds like no charge, check generator output, battery, etc. IF you get much below 10 volts it just won't have enough juice to fire the plugs, and/or run the fuel pump. Also, rotors are notorious for failing. Spontaneous sparkplug failure very unlikely.
George Butz

Dave,
You said >>"Pulled up the hill from the stop sign and it started sputtering and slowing and...it stopped. Would crank up and quit. Several times like it was running the gas out of the carb bowls"and "Let it sit and same thing but then it cranked and stayed running at about 3000rpm with the choke out"<<

Both of these conditions lead me to believe that you are in fact having some sort of a fuel delivery problem,,, Did you seal the tickler pins ?? If you did not, they would indicate a low fuel bowl situation,,
I do not think the ammeter problem is related to your engine quitting

SPW
Steve Wincze

Steve,
Been too busy to install the overflow pipes but they did come in from Moss, so I haven't sealed the tickler pins yet either. I, thought it felt like the fuel pump but still those electrical things going on don't seem to add up either...

Strange but it did crank up finally with the choke out but seems to run a tad rough...

The mystery goes on...and I am still lining up rides to and from work...or walkin...
dave lackey

I hate walking...but that is what you have to do sometimes when your only transportation is a 36 year old B and a 55 year old TD...the adventure continues!
dave lackey

I'm with George Butz. A weak generator could easily cause a poor running condition both on ignition and fuel delivery. Running on choke would mask a low float level condition caused by low voltage. Check the voltage across the battery, and across the fuel pump. Your generator light being on even at 3000 rpm is definitely amiss.

warmly,
dave
Dave Braun

everyone has different experiences to draw on, but if you think it is low volts charge the battery and she should fire up like the days of old. a few years go i drove a renault 30 miles, in the dark, after my fan belt broke. i turned on the headlights only when another car approached.(and that car had the battery in front, engine in rear=massive voltage drop through an EIGHT foot battery cable!!) one difference is that car did not have an electric fuel pump. a short in the fuel pump could cause a large draw and at the same time not deliver fuel. regards, tom
tm peterson

Ok, Dave...makes sense.

Now, explain to a simpleton what meter to use and what wire to hook the thing to....don't want to fry something or meself whilst doing it!
dave lackey

Hi Dave, your ammeter should not show discharge with the headlights on and the engine running at above idle speed, so there is a problem there, probably with the genny. However if the engine cranks over with the starter there should be enough power to run the ignition.

Is the fuel pump clicking? If not that will be an indication that there is a problem with fuel delivery.

I agree with George here it's not the plugs. Could even be that you have managed to seal up the fuel filler cap somehow which is stopping the air from getting into the tank.

Cheers,

Paul.
Paul van Gool

Yes, the fuel pump is clicking...but funny you should mention the gas cap. I pulled the dipstick and checked it before toodling off and it quit a mile away. Wonder how the air could be cut off at the cap by just putting the dipstick back and shutting the cap....hmmmmm.
dave lackey

Dave,
IMHO,,, You said that your gas tank registered 4 gallons when you checked it,,, even if you sealed your tank with that much air inside, you would get a lot more than one mile of driving,,, I would still check your fuel bowls,,, Even it your fuel pump was ticking over, you might have a plugged pump filter which is not allowing the fuel to flow to your carbies at a proper rate to maintain speed,,, thusly , it would sputter and stop,,, then when you tried to start it again, the fuel would have had a chance to fill up the bowls again and the engine would start, and run for another mile,,
Run the car again, and when it sputters to a stop, turn off the ignition and check the level of the tickler pins,, in they are down, the bowls are empty,,,

SPW
Steve Wincze

Thanks, Steve...

Will go out in the garage after work, today, and check it out...

I'm gettin a headache.
dave lackey

Dave - See my fuel delivery troubleshooting guide at: http://www.custompistols.com/cars/dave/ddFuelDeliveryTroubleshooting.htm for checks that you can do to isolate any problems in that area. As for the generator, remove the wires from both terminals of the generator and short the terminals together with a short jumper wire. Connect a multimeter (preferably an analog meter rather than a digital one) set to read 20 volts, between the shorted terminals and ground (negative lead to the generator terminals if hte car is still positive ground). Start the car a slowely increase the revs, while watching the meter. The voltage should run right up to 20 volts if the generator is good. Be careful to not reve the engine to the point where the voltage exceeds 20 volts or the voltage could increase quickly to a point where it will damage the generator. If the generator checks good, then the problem may be in the regulator and I'll let Bob Jeffers take over on how to check that out as he is the expert in that area. Good luck - Dave
David DuBois

Dave L.
Dave DuBois has it spot on. The BIG BIG clue is your ammeter discharging all the time - that is 99% certain to be the generator. Start there for certain, pound to a penny the brushes are stuck or shot.
All your other symptoms stem from no current from the generator.
Good Luck
Graham Smith Honorary Dave
TD/C 7822
G.D. Smith

Dave -- First go through the things mentioned above to insure that you have fuel. One of my tricks is to turn ON the key, wait for the pump to stop clicking, then push the tickler pins down. If the gas squirts out the overflow pipes the fuel system is working!

Now to electrical tests, if the battery has enough energy to crank the engine over then it has enough to run the ignition. However, if a loose connection in the wiring has developed the 12 volts might not be getting to the ignition coil. Connect your voltmeter to the wire on the coil that doesn't come from the distributor, and ground. Monitor this voltage. It should be 12.6 volts or more before you start the engine and should rise after the engine starts to maybe 14.6-14.8 volts. This indicates that the generator is trying to charge the battery. If perchance the voltage before you start the engine is 10 volts or thereabouts you have a dead cell in your battery and must have it replaced.

If on the other hand the voltage across the battery is about 12 volts but the voltage at the coil is not 12 volts then you have a wiring problem. Could be the big brown wires coming off the starter switch are not making good connection, could be the connections at the back of the ammeter are not making good connection, could be the ignition switch itself. You have to trace it step-by-step to see where the voltage is getting lost.

There were some very good diagrams of the wiring in the centerfolds of last years issues of the TSO.

Keep us informed of what you find and between the group of us we will help you find your problem and fix it.
R. K. (Bob) Jeffers

Dave:

My TD hasn't run in years so I can't help you in diagnosing your problem. I found that if the car doesn't run at all, it's a lot less likely to leave you stranded.

However, whilst reading this thread, this thought occurred to me:

What is an admitted mechanical simpleton doing with only two antique MGs as his sole means of transportation?

Either:
A. The ex-wife got the good car.
B. You're not the simpleton you claim to be.
C. You have a pround faith that the main upstairs will save you from calamity.
D. You really do like walking.

Please explain, if you would.
Peter Whelan

Man! There are too many Daves on this Board! We are going to have to start using last initially so we can keep it all sorted out (kind of like when I went to work aout at the local submarine base, if someone came into the area and called Dave, 15 heads swiveled around - yes, there were 15 Daves in the one office). Peter, I thought at first you were talking to me when you said only two antique MGs as his soul source of transportation. My wife and I have just that, a 53 TD and a 66 MGB, both of which have been extremely reliable transportation over the years. Cheers - Dave D
David DuBois

Sorry Dave, I should have been more specific. That post was meant for Dave......not that Dave, the other Dave....you know...Dave.

Maybe you should change your name to Gordon... nah, never mind.

Edit:
C. You have a profound faith that the man upstairs will save you from calamity.
Peter Whelan

one caution before you tear into the generator...the regulators are not solid state...please go through a methodical troubleshooting scheme...if you run with each suggestion as a stand alone solution..you could make your life difficult. the suggestions here are based on the limited info one can provide through a message board...a good first question would be..have you worked on the car lately? if so what did you work on, what was disturbed while you worked on the other problem. the motor only needs 3 things to start..compression, a spark at the appropriate time, and a combustible fuel air mixture. a mechanic for thirty years..90% of the problems are ignition and an empty tank. if you have gas delivered we are back to spark..do you have a good blue spark, is it delivered at the proper time...how do the points look? how does the distributor cap look? i have seen a few cars with a lot of corrosion down in the wire towers on the distributor cap. again, keep us informed as to what you find so we can all learn. regards tom
tm peterson

Once you check your spark and other electrics, another possibility MAY be the coupling between carbs. I had a loose one once that caused symptoms kinda similar. Lou
Lou Van Koningsveld

Peter,
DaveL here...

Guilty of all the above!!!

Now, update...went home after work, pulled out my favorite beverage, changed the plugs in the B and thought about the TD...cranked it up and all is well. Lights strong, runs fine. Ampmeter shows about -4. Turn on the lights...ampmeter shows about -18. Hard to tell when it swings like a pendulum. Rev it up and it heads toward center.

Checked the carbs, now both pins are up and bouncing when pressed down so the bowls are full.

The generator is a C40 Lucas unit. It has no inspection band for checking the brushes so I suppose I will take it off this weekend and have a go at installing a kit from Holcombe Armature. According to the PO, the generator may have 30,000 miles on it...who knows..

Will report back soon now that the B is running okay.
LOL...

dave lackey

Biggest change I found was cleaning the little slots on the armature... went from warning light mostly on, to on below 900 rpm and off above.
(Tried to inspect the brushes and dropped a screw into the gen....had to take it apart.... At noon I couldn't spell 'electricial technition' and by 1:00 I had become one!)
gblawson - TD#27667

Dave L -- From your description the generator is working. The C40 is rated 22 Amps so it should more than handle the headlights. This may say that the regulator needs attention. Be very careful with the description in the Workshop Manual, it is for a 9 post regulator and you probably have a 5 post in your TD.

Have you checked the voltage across the battery? I think you said the dash light goes from full ON with the engine OFF to very dim when the engine is revved, if so the generator is putting out some current but maybe the regulator is limiting how much.

It's my feeling you/we have not gotten to the bottom of this yet. Keep us up to date.
Cheers,
Bob
R. K. (Bob) Jeffers

Hi, Bob:

Just took the generator to a local electric shop and he tested it...50 amps!!! Yowzah... nothing wrong with the generator so I will bolt it back on tonight.

Tomorrow afternoon I have a new 5 post regulator being delivered. Will have that sucker bolted on tomorrow evening.

Curiouser and curiouser...

Will keep you guys updated and I REALLY appreciate all the input...!!!!
dave lackey

DaveL
Well the genny is OK, that'll teach me to jump to conclusions. In addition to checking the regulator, may be worth checking the main earths from the battery?
Good Luck
Graham Honorary Dave
TD/C 7822
G.D. Smith

Update...
Got the new regulator from Holcombe Armature and bolted it on.

Scared to start it up so I think I will pour a favorite beverage and reflect on what I have found so far...

Like the new regulator is not a Lucas one but also looks a little different inside. ?Wassup with that??

Like the old one has a contact on the left side (facing the radiator) that does have pitting and really doesn't line up well at all. It hits on a single point, not flat. The other one looks okay as it comes together flat.

Murphy's law...oh, Lord...what will happen when I turn the key? Flames? Explosion? Melt down?

Think I will pour another...and another...
dave lackey

Dave L. -- Tell me a little more about the regulator you got from Holcombe Armature. What does the outer case look like? How bad was the price? Any indication where it was made, and/or by whom?

I didn't know they were selling regulators!
Sincerely,
Bob
R. K. (Bob) Jeffers

Okay...no flames, no meltdown...but now I am really confused.

The regulator was $45 and looks to have been made in South Africa. The name is "Lectrolyte". From the outside it looks identical to the Lucas. Somewhat more compact on the inside.

Soooooo....I took a deep breath...hooked up the battery. Nothing...good! Turned the key and the warning light came on...good!

Pulled the starter and it cranked right up! Good! Butttt.....why is the warning light staying on all the time? In fact, at 2000rpm and above it pulses at about 3/second. Runs good, though. Ammeter is still showing all negative and wildly swinging just like before.

Then it doesn't run so good and quits again. Checked the tickler pins and they are DOWN. Took a weapon and beat on the new looking fuel pump and it ticked and the rear float bowl musta filled 'cause the tickler pin went up. Beat it again and waited and the front tickler pin went up...

Cranked it again...ran good! Still the pulsating warning light and wildly swinging ammeter. Maybe I need another six-pack of Guinness???

What gives?
dave lackey

Ahhh...the power of certain fluids...

Went back out and took the old Lucas regulator and cleaned the points with emery cloth. Put it back on and cranked it (after a pint, of course). Cranked up and the warning light went off on cue. Ammeter still swinging wildly in the negative. Kept it running and increasing rpm with lights on/off, etc. After a few minutes, the ammeter show charge!!!! at higher rpm's!!!! Seems to be working great, now...

Then, after a few minutes, it sputtered and quit. !@#@@!#@

Checked the tickler pins...yep..down again.

Banged on the fuel pump. Cranked it again and watched the pins rise. Then, after a few minutes they started down again..check ammeter, working perfectly. Then it sputtered trying to stop. Ran around and banged on the fuel pump and it started running good again and the pins went up.

Should I just take the pump apart and clean the contacts? Or just spring for a new one from Moss?
dave lackey

Dave, I'd polarize the generator 1st and if no change on the ammeter I'd try switching the terminals on the amp meter. Current flowing the other direction will now show charge instead of discharge.

LaVerne
LED DOWNEY

Laverne,

Thanks, but now the ammeter and generator appear to be back to normal...which it never was when I bought the TD in June...

Fixing to go out and work on the pump contacts...

Wish me luck.
dave lackey

What a hoot!

Simple. Cleaned the contacts on the fuel pump and burnished with a little sand paper and it seems to have fixed THAT problem. I think the regulator is good to go until I replace it with a solid state. After a few minutes it shows charging when revved up and responds instantaneously...

Been driving my B for 20 years but forgot how easily these contacts can be a problem and yet how easily the problem can be solved.

Think we'll try a leetle trip to Callaway Gardens in the morning...will report back!
dave lackey

Wow, simultaneous problems, and few of us wanted to believe that both could be happening at once. The really big 'Hoot' is that both were solved by the same action, i.e. cleaning the contacts!

Congratulations on a problem well solved!

dave
Dave Braun

... never too old to learn something. I've been monitoring this thread and feel I've learned that one problem can mainfest another. In this case, it wasn't clear which one started it all!

But obvioulsy, cleaning the contacts is a simple routine that we should all perform on some regular basis. Unfortunately, its not that simple of a TF. So again, I am resurrecting my interest in replcimg my "Prince of Darkness" pump, with a good 'ole Yank pump from JC Whitney for a paltry $40.

Gord Clark
Rockburn, Qué.

Gordon A. Clark

Dave, I can't remember if you've taken the end off the dynamo and cleaned the commutator. But doing that, and replacing/unsticking the brushes will ease your mind about that end.

I had a Harting regulator when I first bought my car. I was so incensed when I saw there was no adjustment. My first Triumph had black tape around the seam of the cover of the control box. I have never needed to take that tape off, so I'm assuming it's a good idea to do that. Moisture has killed all of my control boxes, I think.

If my first alternator conversion works well, I may swallow my pride and replace all of the dynamos. And then we have to get together to put the plate on the end of those Denso or Bosch starters into public domain. Along with the common cars that they are from. Great starters from the U-Pull-it or ANY parts store, just save your adapter plate. It really is time to demystify this.
Tom

My TF likes to sputter and misfire after spending a cold night in the unheated garage....condensation? I carry a mini WD40 and remove the distributor cap and rotor, wipe with a rag, and spray liberally with WD, and go on my merry way until the next cold morning. I wonder if replacing rotor, points and cap would solve this minor problem?
SEAMUS
F. HEALY

Seamus
IMHO I doubt that it is condensation,, Does your car sputter and missfire untill it gets warmed up ?? Do you keep the choke on? Does it sputter with the choke on ??

SPW
Steve Wincze

Ta-da!!!

Just returned from a picnic at Warm Springs and the Little White House. All in all about 100 miles round trip and no problems!

Well, went to Cracker Barrel for breakfast this morning and it sputtered to a stop about 2 miles from home...tap tap tap...and we were on our way in 37 F temps. Had breakfast and went shopping. No problems after that. I think the last bit of crud had to be burned off the contact points because it ran great afterwards.

In fact, after we got going, the ammeter settled down and at 3000 rpm was showing +20...at 2000 rpm around +12. Seems to be working better than ever.

Thanks to all who responded on this lengthy post and also to those with whom I spoke on the phone. Now, to return that goofy ammeter to Holcombe Armature...

dave lackey

Dave L -- That 30 Amps, did it ever decrease? At that rate of charge you will soon need a new battery, it will be boiled dry. Sounds to me like your regulator is not working, it seems to me from your description it is just calling for max output from the generator all the time.

To be safe, put a voltmeter across the battery and go for a drive. Tell me what the voltage is before you start the engine in the morning. Then what voltage it gets to when it is being driven.

Ideally it will rise to about 14.4/14.6 volts and steady off at that point. Then the ammeter should start cutting back. Depending on the health of the battery it may go down to 2-4 Amps. If the battery is sulphated it may take quite a few cycles to get it to cut back to that level. If it has a shorted cell it will never cut back, but the voltage measured after a nights rest will be about 10 volts instead of 12.6-12.8 volts.

Let us know what the results of your tests are and we will see if we can help you get the system to work as it should.
Cheers,
Bob
R. K. (Bob) Jeffers

Hi, Bob!

Not sure if I said 30 amps...my ammeter only goes to 20 on either side. It swings wildly at first and then settled down to somewhere between 10 and 14 at 3000 rpm. But then again, at rest, nothing on and turned off, the ammeter read -2. ???

Anyways,the needle at least show increasing + charge when gas pedal is pushed down and immediately drops down when gas pedal is released.

BTW, I misspoke, I have to return the regulator, not the ammeter to Holcombe.

I'll get someone to check the voltage this week and update this post. Thanks!

Best regards,

DaveL
dave lackey

Still goin'...just like the Energizer bunny...

Weird, though, the ammeter, that is. This morning on my 10 mile commute it stayed waaaaay -...turned the car off at the office, cranked back up and it showed positive charge and responded to throttle changes.

Thinking maybe it could be the ignition switch...ah, just another mystery for an upcoming winter day...
dave lackey

Steve:
The car starts up and runs great then starts to sputter and backfire especially under a load. I know it's not in the fuel system because as soon as I remove dist. cap and spray with WD40 the problem is solved until the next cold night in the garage. Maybe the TF is lonely and is trying to tell me to put a gas hot air heater in the garage to keep it company....who knows? The cap looks ok with no spark tracks, but maybe after running a bit the dist.warms up a little and condenses with the cold air in the dist.????
SEAMUS
F. HEALY

SEAMUS
It's very possible that it is in fact asking for a heater!!! BUT,, just humor me on this one,,,, the next time you take the car out after a cold night, drive it till it starts to sputter and back fire,,,,, then, shut it down as if you were going to spray the dist with WD 40,,, BUT don't,,, just wait for the length of time that it would have taken you to open the bonnet, remove the cap, spray the dist, put the cap back on, an then try to start it,,, It just might be a "heat sink" issue,,,

SPW

Steve Wincze

It sure seems like you still have a charging problem, Dave. I have had the ammeter go way minus, though, and it was just stuck at the minus side from the starting load. Tapping the gauge always made it come back to normal.

Understanding the way the regulator conrols the charging is important. Right after you start the car, the ammeter should be going plus fairly high to replace that energy, but only for a short while. After it has run for a minute or so, the gauge should be running close to the middle. Not going way up with the RPM's. You can see the regulator cut the charge down as you reach 2K RPM or so. If your gauge is telling you it's charging too much, always going way up with RPM, you will be burning up a battery, and maybe lights, etc.

This condition is what prompted me to go alternator conversion. The old points style control box just wasn't reliable enough for me any more. A solid state one might be a good, more original but modern, solution.

Time will tell if my decision has been a good one.
Tom

Dave,

I agree with Tom. You still have a problem.

You might want to clean the points in the regulator again. The contacts and any build up are very hard. I had to clean mine aggressively with a file. Once they are clean a stock regulator works just fine.

You might want to top up your battery with an external charger before your next drive. The generator (or even an alternator) is not meant to charge a low battery. It is only designed to replace the energy used to start the car.

Any chance your ammeter is going bad? You might want to pick up a test ammeter. It should not swing negative on start up. The starter does not draw current through the ammeter, only the fuel pump and ignition.

Good luck!
Evan
Evan Ford - TD 27621

Dave L.
If you continue to have this problem I would check the filter/screens in the fuel pump and the screens where fuel lines enter the carburetors. Sounds to me that you have a fuel starvation problem and you indicated that thumping the fuel pump lifted the tickler pins. Also the filter screen in the gas tank, where the gas line attaches to the tank. If you have just replaced the gas tank cap gasket, you may have no vent . If this were the problem driving the car with the cap not clicked tight, ¼ tank of gas or less and the car ran ok, would indicate that you have no vent. If it turns out to be dirty screens in the tank, fuel pump, or carburetor cone screens, if you don’t have a fuel filter before the fuel pump then you need to add one. Purolator makes one that is very small and clear glass which can be mounted on the scuttle under the fuel pump. It will be interesting to see what the problem was. Keep us informed. John
JOHN

Evan, yes I may have a bad ammeter. Or some other wiring dilemma. Don't know for sure at this time, and I'm sorry if I gave any false info on the way the meter is supposed to work. Mine behaved that way after a start occasionally (had to tap it to go back to center, it would be stuck at negative).
Tom

Steve. Change your dist cap.. Sometimes antifreeze gets spilled on cap and the cap absorbs some. During the night it also attracts water moisture. You cannot get the antifreeze out of the pores, at least I have not found a way. When you spray the cap all you do is remove surface moisture and at night it re-condenses.
Sandy
Sandy Sanders

Dave,
This sure sounds like the same problem I had with the TF at start of the summer and disscused on this BBS!
"if you don’t have a fuel filter before the fuel pump then you need to add one"
I had one on my car ...and that was the problem!
Get a "clear" one if not the glass one, Nappa makes some cheap in-line filters.
I use those on my TF ...but that is because of the location of fuel pump on the TF (near rear axle..and not in sight).
With the TD and pump being right on the scuttle wall I think I would go with what John said as it would look better!
Cheers,
David 55 TF1500 #7427
David Sheward

Hi DaveL.

C'mon don't be shy, you sorted that ammeter problem yet?
The earths OK?

Graham (honorary Dave)
TD/C 7822
G.D. Smith

Hi, Graham...

Well, the only thing I can say is that everything is working just fine. Been driving everyday and no problems!

Lights light, fuel pump pumps, ammeter appears to be metering, life is good.

Thanks,

DaveL
dave lackey

Dave S. and anyone else who has a filter between the tank and the pump, or is thinking of adding one - Watch that filter like a hawk and clean or replace it if it even looks like if is getting dirty. The SU fuel pumps have a swamping resistor in parallel with the coil. This resistor consists of a length of very fine nichrome resistance wire wrapped around the outside of the coil and connected to each end of the coil. The purpose of this resistor is to provide arc suppression for the points, either by itself (in the case of the early pumps or in conjunction with a capacitor on the later pumps). If a filter between the tank and the pump clogs up with debris to the point that it cuts off fuel flow, the pump will stall in a current on condition and if the power is left on, will over heat and burn out the resistance wire. Once that happens, there is no longer any arc suppression for the points in the pump and the life of the points will be greatly reduced. The big problem is that when one sees that the points are burned, they just get a new set of points and install them in the pump, thinking that they have fixed the problem. Since the resistor is inside the coil housing, it can't be seen and whoever works on the pump goes along slightly weight challenged (a bit of Political Correctness here), dumb and happy, only to have the new set of points fail in a short time.

The pickup in the tank has a filter screen on it, as does the inlet side of the fuel pump and the inlet to the float bowl. These filter screens are all one needs to protect the pump and carburetors. They suffice to block rocks and small birds and the smaller stuff will go on through the pump and settle in the float bowls. If there is a lot of sediment collecting in the float bowls, the proper (and long term) solution is to get the tank cleaned and sealed rather than sticking a high efficiency filter in the line.

A word of warning on sealer used for the fuel tank while we are on the subject. Make sure that the sealer used is resistant to all the nasty stuff blended into today's fuels, including various concentrations of ethanol. I put aircraft sloshing compound in the tank of our TD when I restored it 25 years ago (the only sealer that was available at that time). Recently, the sealer started dissolving in the fuel and getting dispersed throughout the fuel system. I would up with check valve disks in the fuel pump and needle valves in the carburetors glued shut after the car sat overnight. Removing the sloshing compound required soaking the tank at a dip stripper for so long that the brass of the drain and outlet fitting on the bottom of the tank was eaten away and I am having to repair that. Just a word to the wise. Cheers - Dave
David DuBois

YIKES!

TD quit again...but I wuz expecting it this time! Left the office at dusk and turned on the lights...something just didn't seem right. Ammeter showing mostly discharge and the warning light was barely coming on. Lights seemed to dim and it just didn't feel right.

Sure enough 1 mile from home, I felt it wuz gonna quit on me and turned into Brusters with enough momentum to pull into a parking spot...and it wuz DEAD. No lights, no response from ignition key, nuttin...

Opened the hood. All's okay. Touched the ignition switch and ouch! it wuz hot! Soooo...stuck my head under the dash and found the brown/blue wire hangin in the air...

Simple matter to reconnect in the dark and drove her on home. Ammeter is working just fine now. Me thinks that the weird ammeter stuff wuz from the wire being loose.

Oh, well...all's well that ends well...

Best regards,

DaveL
dave lackey

Good to hear you finally found the problem!

Dave, regarding the filter in the fuel tank, is this easily cleanable, say with a tank full or half full of gas?

Scott
Scott

David DuBois,
Good Point! I should have stated that my in line filter is "AFTER" the pump ..not brfore it! Thank you for making that need clear!
Cheers,
David 55 TF1500 #7427
David Sheward

Scott - "regarding the filter in the fuel tank, is this easily cleanable, say with a tank full or half full of gas?" Only if you lik to work with fuel running on the floor until you are finished. I hooked a hose to the oule of the fuel pump and pumped a quarter tank of fuel into a 5 gallon bucket, then put an oil drain pan under the outlet fitting of the tank and remover the fuel line from it and let the remaining pint or so of fuel drain into that and finally removed the outlet fitting with the filter. Cheers - Dave
David DuBois

Okay,
TD starting very sluggishly and finally would not. So, I just replaced the battery.

The saga continues...

Gonna go back and re-read the posts above and see what's next...

In the words of Toby Keith...I love this caaaaarrrrr...

Octagonally,

DaveL
dave lackey

Graham (Honorary Dave):

Need to work on the B fuel pump this evening and will not have time to check the earth on the TD til this weekend. Will report back.

Think I will take the regulator back out and file down the points...the points that are easiest seen did not fit together FLAT...just kinda met with a point...I know it is hard to describe. BTW, does anyone know what the point gap is supposed to be?

Best regards,

DaveL
dave lackey

This thread was discussed between 08/11/2006 and 12/12/2006

MG TD TF 1500 index

This thread is from the archive. The Live MG TD TF 1500 BBS is active now.