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MG MGB Technical - ELECTRICAL ISSUE

1979 US MGB. Key in ignition, turn to ON position, horn, lights, signals, turn to START and off and running. Drive a bit, car bucks, tack bounces and then ZERO. Car stone dead. Turn key OFF, then ON, Then to START, no lights, horn, signals - nothing. Battery is up. Wait a few minutes, Turn key ON, lights, horn, signals, Turn to START, and we are back running. This issue has just developed. My thought process is the ignition key switch is the culprit. Any ideas???

Thanx in advance

Cheers

Gary

79 MGB
gary hansen

could be many more things (or the ignition switch)

you need to do a step by step diagnostics

did the rev counter go erratic or just drop?

not sure what you mean by the battery was up but any electrics start with the battery (is it held secure - on to battery posts, clamps, leads and all major earths are they all clean secure and protected - then moving on through the electrics from there)
Nigel Atkins

Nigel. The car just cut out. The battery is charged and in good shape, The car just quit..... No power, no nothing. Then after a few minutes after turning the key OFF,ON,START it started up fine and everything worked. We checked with a test light and we had power to the switch and that is where it ended.

cheers

Gary
gary hansen

Gary,
always best to have a battery in good condition and well charged especially when you have electrical or starting problems - so good

but I was more thinking of what comes after the battery internals -
. is battery held securely - if not you can have go/no go
. battery posts and clamps - clean, secure and protected
. battery leads and all major earths - clean, secure and protected

from just looking at a wiring diagram (which you'll have in the invaluable Driver's Handbook if you have a copy) as well as the ignition switch you have connections on the ignition relay and the fact all the electrics went I wonder about your fusebox connections and the box itself

obviously you'd need to disconnect the battery to check the under side of the fuse box

have a look here - http://www.advanceautowire.com/mgb.pdf

and on Paul Hunt's excellent web site - http://www.mgb-stuff.org.uk/hammertext.htm
Nigel Atkins

Don't know how different late US wiring was, but the horn, lights, hazards, interior lights are all permanently live irrespective of key position, at least in in UK spec. So if these are dead as well, would suggest it is problem on the main feed from starter solenoid connection to ignition switch and fuse box (Brown). If everything is dead without a key in place would suggest also incorrectly wired switch. BUT US spec????
Allan Reeling

Follow up.
Just had a look at late US wiring diagram. Between the starter connection and the switch and fuse box there are a couple of bullet connectors, always a good place to start, those little blighters!!
Allan Reeling

As Allan says all those things are permanently live, and some of them are not fused, so if they don't work when the problem occurs it's a major power supply failure.

Ordinarily once the engine is running the alternator will supply all the electrics even if the battery fails. It's not going to be the ignition switch as that doesn't control the horn, lights etc. The fact that it cuts out as well indicates to me that the problem is in the brown wire that comes up from the solenoid to the rest of the cars electrics. There is a double brown up from the solenoid to some kind of branching point somewhere, probably in the engine compartment as one wire goes to the fusebox and the other to one of the connectors behind the dash. I don't know if that is a sealed connector or is plug-able, if sealed the the problem is almost certainly at the solenoid. I had a similar problem there a few years ago - disconnect the battery earth cable, remove the bolt-through terminals from the solenoid stud, clean them up with emery cloth or similar, and reassemble with some kind of grease or Vaseline. If it's a plug-able connector then it could also be there.
Paul Hunt

OK. Correction on my part. Car started, ran and suddenly tach bounced then ZERO. Turned key to OFF, then ON, then START, NO start. I had no directional signal or any other accessories that required the key switch to be in the ON position. including START position. Test light to battery indicated fully charged. I DID have headlights, brake lights, I do not know if this sheds any light on the dilemma.

Thnax again for the input

Cheers

Gary
gary hansen

Gary. Do you have a wiring diagram? If not, you need to obtain one. They may be downloaded off the internet, then expanded so that they are easily used. I had mine laminated and have used the same one for something over ten years now with complete satisfaction.

Next, examine all of the common points between the battery and the systems that quite working when you had your problem--e.g. battery posts, ground connection for negative terminal, starter terminal connection for battery positive and alternator wires, etc. Go through these connections, from front to back, cleaning and tightening them as you go. You may find one that seems the most likely culprit (loose nut on the starter is not uncommon and can cause problems) or it may simply be some combination of problems each adding to the unreliable nature of the car.

The ignition switch may be part, or all, of the problem. But, until you check out the system in a systematic manner, you may find one, or more, problems but not the root cause of the malfunction.

Les
Les Bengtson

Alan & Paul..Looked in the engine compartment. Noticed two cylindrical shaped items. Both are the same size and shape. Both are black with white numbers on them. 87, 86, 85& 30/51. Brown wire runs to both, and are located on the right hand inner wall. The first one is closer to the front of the car and the second one is partially hidden by the collapsable hood prop. Is this the items you were referring ?? The brown wire does appear to go into a blue wrapped harness which disappears into the passenger compartment on the right had side of the car

Cheers

Gary
gary hansen

Gary. Front one is ignition solenoid and the rear one is the starter solenoid. Both can go bad and give you the symptoms you display. But, so can other connections, mainly the main connection at the starter.

Les
Les Bengtson

Les.. Looking at the rearward mounted item, it appears to need some cleaning up. I will disconnect the battery and clean up all the connections on both items as well as the fuse box and cables.

We just moved to Florida from New York and still unpacking boxes. Found my Haynes MGB repair guide so now I have some reference to work with.

Thanx for the input to you and everyone else.

Will repost when I'm done

Cheers

Gary
gary hansen

Gary. It is, in theory, possible that both the ignition relay and the starter relay will fail at the same time and in the same manner. In practice, however, I have never seen them do so. Thus, the symptoms you describe, to me, indicate a problem further back in the system. The possible failure points would be the battery and the battery terminal clamps, the ground from the negative terminal of the battery cable to the frame, the mutual joint of the battery cable (positive) and the brown wires from the alternator at the main terminal of the starter, and the ground strap from the transmission to the transmission cross member. Problems at the starter are the most common cause of the fault you describe.

Les

P.S. The Hayne's manual does not cover the depth and breath of information that the Bentley Publishing Company's reprint of the Factory Workshop Manual does.
Les Bengtson

That's a very different description from what you said to start with! So are you saying now that only the ignition circuits are failing? And all the non-ignition circuits like lights, horn and interior light are working normally when the problem occurs?

"Car started, ran and suddenly tach bounced then ZERO. Turned key to OFF"

Did the engine stop when the tach dropped? Or only when you turned the key off?

The black cylindrical things are relays, not solenoids. I'm not being picky but it's important to distinguish between the relays and the starter solenoid on the starter, for example, when describing problems and symptoms.

When you turned the key to start did it crank but not start? Or not even crank?

If it cranked but wouldn't start, and the fuel gauge was dropping to zero with the ignition switch on, then the problem is going to be with the ignition switch, ignition relay or connections. Can you hear the ignition relay clicking on and off as you turn the ignition switch on and off? You should do, although perhaps not as easy single-handed on an LHD.

If it didn't even crank, then the problem is more likely to be in the brown circuit. As this fault comes and goes I'd put money on it not being both relays that are failing and coming back at the same time every time.
Paul Hunt

Paul..When the tach dropped to ZERO, the engine quit immediately. While coasting, I turned the key to START and nothing... No starter and no instrument indicator lights either (IGNITION). It was as though the key was in the OFF position. We had Headlights, Horn, I'm not sure about directionals.

Cheers

Gary

PS: I just found the rearward relay and noticed it was rather untouched. I replaced the forward one a few years back.
gary hansen

Paul. You are perfectly correct, relays, not solenoids. As I have seen the parts quality available to us, and have had expensive engine rebuilds destroyed because of such trash parts, I grow increasingly less interested in old cars. Hence, my mind is not always as attuned as it should be. However, the indications that Gary lists are somewhat contradictory. If he had headlights and horn, particularly at the same time, it commonly indicates that the battery, its connections, the starter terminal and the ground connections are sufficient to allow the starter to turn over. The fact that it seems not to have worked might tend to indicate that the problem truly is at the starter switch or the brown wiring going to it. I have seen both the starter relay and the ignition relay fail, but never have seen both fail at the same time, then recover sufficiently that the car can be restarted.

Les
Les Bengtson

What gauge wire is the brown wire in the MGB?? I will go through the Brown Wire Trail from the starter solenoid to the battery (after disconnecting the battery) and replace is needed.

Cheers

Gary
gary hansen

Brown usually goes no further than the starter solenoid. Alternator feed is probably 66/0.3mm, feed to ignition and fuse box 44/0.3mm. Gary, there is nothing particularly unusual about the relays. The only bad ones I've come across are the 6R4 copies, these are real tat.
Allan Reeling

As Les observes Gary has now given us three different sets of symptoms which makes it difficult for us to know which if any are truly the case.

If the tach dropped, the engine stopped, and turning the key to crank did nothing, but you still had lights and horn, then the implication is that it's a failure of the brown supply to the ignition switch. Two browns come up from the solenoid to what appears to be a 4-way connector with the two browns are connected together there as well as at the solenoid. A third brown seems to come up from the solenoid to the starter relay and the hazard fuse. After the 4-way connector one brown branches off to the fusebox and ignition relay, and the other to the headlight switch and the ignition switch. The only single fault that meets the latest set of symptoms is if the brown between the light switch and the ignition switch has failed, or the ignition switch itself is at fault. Out of the two I'd say the latter is more likely, but to get to the ignition switch it goes through a multi-way plug and socket by the steering column, so it's possible that pin has become partially pushed out and the tips are only touching.

As it's intermittent the easiest way to deal with this is temporarily poke a test probe into the brown connection in the multi-way, the ignition switch side, and connect that to a meter or bulb placed where you can see it when you are driving along.

That should be on at all times (so perhaps disconnect a bulb at least when parked if you don't have a battery cut-off switch), so if it goes out when the fault occurs you know the problem lies back towards the light switch. Remove the probe and push it into the other side, still on the brown wire. If things start working again as soon as you do that the chances are that connector is the problem, other wise wait until it happens again.

If the meter or light is still registering you need to move the probe to the white wire, which will only register when the ignition is on of course. That will almost certainly go out when the fault occurs, confirming that the supply through the ignition switch has failed. But seeing as how it doesn't run or crank when the fault occurs, the fault isn't going to be in the white itself or you would be able to crank but not start.
Paul Hunt

OK. After removing the surround on the steering column (& breaking the light switch) the test light indicates power to the brown wire at ignition switch and to the multi- plug to which it is attached. There is also power to the brown wire at the headlamp switch. Following Paul's posting, the connecter does not seem to be the culprit. The white wire seems to work as you indicated also

Now looking in the engine compartment, I do not see wires leading to the starter solenoid. Is there some sort of cover on the topside of the starter which shields the solenoid or is it located from the underside?? ( My electrical knowledge is VERY limited and I thank you for your patience.)

I removed the rearward relay and cleaned the heavy crud from the terminals tabs and replaced all the female connectors which also were loosely attached and corroded. The brown wire on the relay had a loose and corroded connection. Started the car and it came alive instantaneously. Not saying this solves the issue, but at worst it may prevent a future issue later.


Cheers

Gary
gary hansen

as well as being involved in specific diagnostics you learnt a basic - wires, connections and switches all need to be clean, secure and protected

there are lots of wires, connections and switches on the car a little crud or poor connections on a few connections or switches can have an accumulative effect on something working well, not very well or even not at all

lack of use (and testing) can deteriorate many electrical items on the car in the same way that lack of use of the car can deteriorate the car generally
Nigel Atkins

Ok. Now it ran fine to the grocery store and back. Then later on went to put car in garage it cranked and did not fire . It is getting fuel but now it does not seem to be getting spark. Yes the battery cables are loosely connected,but it did not fire .

The brown wires through the ignition switch tested well and now the relay wires are are clean. I will continue my clean and crimp campaign tomorrow and post my progress.

Ordered new headlamp switch and wiper switch as well.

Cheers

Gary
gary hansen

This is yet another symptom set! Either you have several separate problems which are independently coming and going - which sounds increasingly likely, or there is an error in diagnosis and symptom reporting.

A problem with the brown wires at the starter would kill everything, not just the engine but still allow lights, horn etc. to continue to work normally.

It's not just a problem with the relays either, whilst a problem with the starter relay may well prevent it cranking, it wouldn't cause the engine to cut out once running.

Likewise a problem with the ignition relay might well cause the engine to cut out, and not to restart, but it wouldn't stop it cranking.

When you are testing the brown and white at the ignition switch or anywhere else you have to be sure that the problem is evident both before and after testing. Any joggling in the vicinity of the fault e.g. the ignition switch connector could well cause the fault to go away, hence you see 12v on the brown and the white as you should. If the car now starts, then the fault has gone, and could well have gone before you made the voltage tests, hence your tests were inconclusive and you will have to wait for the fault to occur again. That's why with intermittent faults I leave meter/light connected while driving normally, so I can look at the indication the moment it occurs, i.e. without any joggling of wiring etc.

Originally the starters were fitted with the solenoid and hence its connections below the motor, arrowed on the attached picture from Clausager. You should be able to see the solenoid and some of the wires by peering down past the edge of the bonnet aperture, above the relays, easier on an LHD than an RHD without the steering column in the way. However you would need to access the connections from underneath the car. As I said before make sure you disconnect the battery earth cable before doing anything with the battery cable stud on the solenoid.



Paul Hunt

Hi Gary,
I might be seeing stuff that isn't there but just in case -
>> ... it cranked and did not fire ... does not seem to be getting spark. Yes the battery cables are loosely connected,but it did not fire.<<
any cable(s) connected loosely especially the main battery cables (and earths and connections) wont work well (and can overheat) starting the car takes a lot of electric so the connections and leads need to be at their best

>>Ordered new headlamp switch and wiper switch as well.<<
don't rush to replace parts if you don't need to as many modern made parts are very poorly made and some only last weeks were the originals have lasted decades, switches can often be cleaned up and lubricated and just by fully operating them dozens of times during this process can have them working well - then you need to use them or test them to keep them working well, easiest way to do this is to drive the car regularly all year around

I use a little electric contact spray (switch fully disconnected of course) at the top and bottom gaps of the switch to help with its operation

as you have, the spade pins can be cleaned and spade connectors tighten, you could also add a very small amount of electrical contact grease to help prevent further crud build up
Nigel Atkins

This has been quite an experience. Found the starter solenoid under the rubber boot which covers the starter. Cleaned all connections and replaced the wire female connectors to the solenoid. Replaced the positive battery terminal connector and sprayed the connectors with electrical cleaner.

So far the most common denominator has been loose and corroded connections throughout. I am sure this why my issues have been several as well as vague. Now I think the battery has packed in.

The headlamp switch broke in several pieces, so a new one is forthcoming.

The engine now cranks. The battery is so weak now that even the horn barely sounds. This after the battery was on trickle charge for several hours. The battery is quite old.

The positive cable goes to the starter solenoid. The negative cable goes to.....??? My car seems to have two cables coming from the negative terminal. One appears to connect to the mounting bolt of the starter on the engine block, but the other.....?

Again, many thanx to all of you for your input. I will keep chipping away at this until there is a resolve and keep you posted as to the progress. We all learn from these issues.


Cheers

Gary
gary hansen

"The engine now cranks. The battery is so weak now that even the horn barely sounds."

If it's got the power to crank then the horn should be no problem for it, considering that the starter takes at least ten to twenty times the current that the horns do!

If you have two horns and they are both weak it's more likely to be bad connections in the horn circuit. The steering column can be a cause of a bad earth to the horn button, but your car should have a different arrangement with a 12v supply from a purple wire to the horn button, which is then extended out to the horns on a purple/black, and they pick up an earth from their mounting brackets. Monitor the voltage on the purple/black when someone is pushing the horn button and you should see 12v.

If less than that check both side of the multi-way connectors for the column switches, for the purple and the purple/black. For some reason there are two purples here - one for the horns and the other for the headlamp flasher, so you need to check both. You should have 12v all the time on the purples (may drop slightly), and with the horn button pushed 12v on both purples and the purple/black.

If you have 12v on the purple/black at the horns with the horn button pushed then check the body of the horn, and its bracket. If you have any voltage there the earth is bad. Each horn has a separate earth of course, so in theory only one at a time should go bad.

"My car seems to have two cables coming from the negative terminal. "

Negative terminal of what? Originally the negative terminal of the battery would have been attached to the body close by, then there should be an earth cable bolted between the body and the gearbox by the rear crossmember on later cars, between the body and the engine bypassing the left-hand engine mount on earlier cars. The starter does not have an earth cable, it gets its earth from it's attachment to the engine.

I have heard of people running an earth cable all the way from the battery to the engine, but it's simply not required, the body offers a lower resistance path than any likely cable does.
Paul Hunt

Went to the garage this AM and turned the key. The car turned over v-e-r-y s-l-o-w-l-y and started!! This tired and exasperated old man was happy!!! While running, tested the horn and directionals etc and they work fine. I do think the battery has done its due. I have owned this car for 12 years and it still has the battery it came with. So yes it is time to get a new one.

Thanx again to all. I hope this thread helps others who have had the same issues. After the new battery is installed I will post the "epilog" to this saga

Cheers

Gary
gary hansen

Gary,
putting a 12 year old drained battery on trickle charge for a few hours wont have got it back to full charge if it's really drained, you need overnight or 24 hours

you could get some tablets to help with the battery and fully and properly recharge it - or - I'd recommend in your case that you do get a new battery in case of future electrical issues where a few hours of trickle charging could bring it back to full

a very good way to keep the battery in good condition and charged is to drive the car on reasonable distance journeys (25+ miles)

even with a new battery all connections and wires need to be clean, secure (tight) and protected (insulated)

these John Twist videos will help you understand how important the battery is plus go on to other parts of the electrics and there are another 200+ to help you -

24 Car Batteries - http://www.youtube.com/watch?v=UnbQ2G5K2zI

Lucas Electrix The Battery - http://www.youtube.com/watch?v=_Uk53AYZ_2o

20 MG MGB 77-80 Electrix - http://www.youtube.com/watch?v=XGmFf5Dre8Y

just three of the 200+ most have some relevant content to your car
Nigel Atkins

The best way to get the longest life from your battery is to keep it fully charged at all times. When my car isn't in use, I keep my batteries connected to a Battery Tender. It charges the batteries and shuts itself off when the batteries show full charge. It doesn't draw any power once the batteries are fully charged. When It senses a voltage drop, it comes back on and charges the batteries again. My last pair of batteries lasted 13 years and the pair before that lasted 8 years. The Battery Tender costs about $50 and is well worth the investment. I also have one for my motorcycle battery. These batteries normally last only about 2 years on average and cost in excess of $100. Mine is now 7 years old and still going strong. RAY
rjm RAY

Fully recharging a significantly drained battery either needs a battery conditioning charger with a 'recovery' feature, or a conventional charger on a higher voltage than is normal with a trickle charger or even the voltage typically output from an alternator. At one time Mercedes were having to select alternators with voltage regulators at the upper end, as those at the lower end were resulting in knackered batteries after just a couple of years. An alternator max is typically 14.7v, whereas the dynamo voltage regulator could go as high as 15.5v and this is what you should be aiming for. This shouldn't be left on for 24 hours as it bubbles the battery, and it might need topping-up afterwards anyway. Note that the voltage goes up as the battery becomes fully charged.
Paul Hunt

I've found batteries generally to be very robust, if the car is to be left standing for a considerable time then I'd use a conditioner but that's still best used between regular use of the car for reasonable length journeys

apologies I was too literal with 24 hours and of course there the usual H&S and care of battery considerations, it was just an example to distinguish between being on 'trickle charge for several hours' and bear in mind Gary did put in his early posts that 'The battery is charged and in good shape' so possibly it didn't need much recharging if at all and he has an alternator car

I thought despite being able to recover many batteries that as Gary is new to the car and electric problems and that his battery is 12 years old he'd be better with having a solid base to start from with a new battery

a good battery is one of my priorities as I can't stand a car that wont start or is difficult to start even if it's a classic that's been sitting outside in the coldest part of winter unused for a few weeks I still expect it to start and be fully reliable, a lot easier to achieve if the car is regularly serviced and regularly used all year round
Nigel Atkins

Removed the battery and and super cleaned the terminal posts and cable ends. Charged the battery for 6 hours Found more corroded tabs on a relay(?)located under the ignition relay and cleaned the tabs and replaced the connector ends.

With the test light, got a bright light from the battery and the ignition switch on both sides of the multi-connector.
Engine cranked over very quickly and started instantaneously.

Very happy that a car that is half my age didn't beat me, I took it out for a run, and it performed very well. Seemed to have more power, tach seemed steadier also.

Put everything back together after shutting it down. Went to start it again, only to have it crank v-e-r-y s-l-o-w-l-y again. This time I held the key in the START position and then the starter picked cranking speed and the engine started.

Now the TACH sems to take longer to register at start than it did before. So I guess we're not done with this.


Cheer

Gary
gary hansen

Gary,
might (or might not) be switch and/or sloppy worn key barrel try using the spare key

I alternate the use of my spare keys (6 months) so that I always know where the spare keys are and that they all work and to give more even wear (particularly important with the modern car with remote) and personally I can't see that hanging several pounds of other keys from the ignition barrel can be a good idea

the tach, I don't know on your car but on mine I have to tap the glass or rev the car to get it into life - at one time I didn't need to but it came back, I've no idea what caused the problem to go away or return - I just live with it as others seem to have this also

do remember you need to also check that all the earths to the relays, engine/g/box/other(?) are all clean, secure and protected

check and clean the connections to and on the starter motor and that the starter motor is connected securely itself, no loose nuts/bolts

you may need to clean the the ignition switch itself and it's connections, look to see if the spades are very loose or poorly held to the switch

you can lubricate the ignition barrel (and other locks) with a little graphite powder (this can make an amazing difference to how the key feels in the lock)

all this cleaning work is obviously done with both sides of the battery disconnected (disconnect earth side first and reconnect it last)

remember with electric connections all need to be clean, secure and protected - modern female spade connectors seem to become loose in a short time whereas the original ones could be fine still after decades
Nigel Atkins

ETA: for earth connections to the body of the car these need to go to clean bare metal somehow often the threads of a captive nut or hole in body metal (the metal can be protected by electrical contact grease) but a slight bit of rust/crud/muck can spoil the electrical contact

screw connections just going through a threaded hole in the body are best to also have a grip type washer to increase the contact area
Nigel Atkins

A problem with the ignition switch, or relay, is going to cause non-cranking, not slow cranking. Slow cranking is caused by insufficient voltage reaching the starter motor, or possibly the engine being harder to turn than normal for some reason.

As such you need to do some proper diagnosis, you could go on cleaning and much worse replacing things for ages and still not land on the root cause.

When it is slow cranking you need to put a meter on the battery posts - not the connectors - and measure the voltage. A good battery should show about 10v. Then put the meter on the battery cable stud on the solenoid and the starter body and measure again. The current and voltage fluctuates while cranking as each piston approaches TDC on its compression stroke so you may have to use an analogue meter, a digital may give a different reading each time or simply not settle. The difference between the two readings show how much is being lost in all the connections including the engine/gearbox earth strap. You should be able to get this to less than 0.5v lost, I have seen 3v lost in just one leg in the past. If you can get to the link cable between the solenoid and the motor then check there as well in case it is the solenoid contacts that are causing the problem, although not all are accessible.
Paul Hunt

there might be more than one problem here based on what's been put before

I agree a step by step diagnostics is required and not to replace anything for the sake of it but also see no harm in cleaning up connections as this is not only worthwhile in itself it will also help with hands on familiarisation of the electrics and started system - to solve this/these specific current problems is great but a broader understanding will help with later problems and build confidence

Gary, like myself, may not have an analogue meter or willing assistant to help where three and four hands are required - but here I could be speaking of myself and not Gary

not that many threads do but I think they work best to resolve the stated problem when the poster answers questions from someone very knowledgeable like Paul and then tests can be done and the poster comes back and give results so that the next step of the diagnostics can be taken which could be more questions and/or tests
Nigel Atkins

.....

dominic clancy

I never understand these jokes about Lucas parts as many last for decades without trouble whereas with the modern parts it's a matter of days or weeks

plus

unforgivable - that looks like an early Triumph Spitfire with the steering wheel on the wrong side ;)

:)
Nigel Atkins

OK!! It seems to have come down to Ignition Switch assy. Replaced the switch, recharged the battery. Turned Ignition Switch to ON position and the "IGNITION" light was very bright and the car started right up. Went for a ride. came back home shut it off, and restarted 15 minutes later, and it stared right up again.

Now I am watching the battery, I will have it tested to be sure it "is on its way out" and replace. Hopefully this is the end of the saga.

I feel confident the symptoms the car had was due to all the factors with the main culprit being the Ignition Switch. Everything else I did was an improvement to the overall electrical system as the lights and ignition system seem to "perform" better. This difficult to do without any electrical diagnostic equipment other than a test light.

Many thanks to Paul, Nigel, Alan, Les,et al
for your patience, and advise to get this electrical dolt through it. You are the best.

Cheers

Gary
gary hansen

if it was the ignition switch - and personally given what you put before and now I think that highly likely - then it would have been the connections on/within the switch so it should show you how important it is to have these clean, secure and protected and by doing so how things improve

crud on the fusebox connections or fuses can often effect the circuits so just cleaning those can made a big difference - that why I say start at the battery and work forward to the end of each circuit, then you won't have things like dim lights and poorly performing electrical items

personally I don't think you need much more than a test bulb for most stuff on the cars

I'd recommend you have one very long twin lead made up that can reach from the battery to the extremes of the cars electrics easily and then make up various connectors as require to connect to items so that you can do direct tests from the battery

please check out the John Twist vids before disposing of the battery - I don't want you to be like the majority of classic car owners, i.e. tight-fisted but as I put before a fully recharge of the battery and perhaps some fizz tablets could extend its useful life

PREVENTION IS BETTER THAN CURE - you might have cured this problem but if you continue to fully and properly service and maintain the car you could prevent a lot of future problems

most servicing work boils down to cleaning and lubing

have a look at the servicing schedule and details of how to do the work in the Driver's Handbook most of it will be easier than finding the solution to this problem so well within your capabilities

don't wait for the problems prevent them, regular driving can do much of this too

over and out
Nigel Atkins

Thank you Nigel. I have owned this car for 12 years and have pretty much been able to work my way through it all. I do consult this site for "re-enforcement" of diagnosis to be sure I going the right way. These cars are rather different. This issue realy "threw" me. There was so may items, and the ignition switch kept working and failing. Each time I cleaned a circuit, the car worked better then the switch would fail or partially fail (if that is possible). Now the IGNITION light is very bright when switched on. Brighter than it's ever been. I will check again tomorrow.

Cheers

Gary
gary hansen

Gary,
you got off lightly I had a BL car where the ignition switch would smoke - and then so did its replacement so that had to be replaced - same car had a column stalk switch that also sometimes smoked luckily for me I went elsewhere for this switch and the chap that supplied the poorly made new replacement (as that's all you could get unless s/h) checked it and done finishing work on it so that it was usable and reliable

well done on getting yours sorted

keep driving the B regularly
Nigel Atkins

I'm normally an optimist but I have to say here "Don't be too sure". As I said before the ignition switch by itself can't cause slow cranking. All it does is operate the starter relay, which takes very little current. That operates the solenoid, which takes more current, and the solenoid operates the starter motor which takes a lot more current. The only other possible cause of slow cranking is if the solenoid is chattering when you crank, but you've never mentioned that.
Paul Hunt

Paul: I did notice when the battery was low, the solenoid would chatter prior to the starter cranking slowly. When the battery was "full", the starter engaged and turned quickly no solenoid chatter. Again the battery is the same one that was in the car when I bought it 12 years ago. Also the car only goes about 3000 miles a year. That is not really a good life for a battery. I'm surprised it has lasted as long as it has.

Cheers

Gary
gary hansen

Gary,
Get a battery conditioner/charger, Accumate is one. These are the controlled trickle chargers which keep the battery in good nick and are connected when the car is standing. They have a lead which is permanently connected with a plug/socket arrangement. Your battery will always be charged and will last longer on infrequent usage.
Allan Reeling

Took the battery out and had it tested. Dead cell. Age of battery December 2000. Install new battery. Car stars up in a snap. Went out to put fuel in it. Stared right up in a snap. Went for a ride 25+ miles. Came home shut it off it restarted in a snap. So with guarded optimism, This saga is over and now just enjoy it until the next item appears.

Again, thanx to all

Cheers

Gary
gary hansen

That's more like it.
Paul Hunt

This thread was discussed between 31/10/2013 and 19/11/2013

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