Ideas to stop fuel vaporising please

[RobSun]

Does the coil get hot, like really hot?

Cant answer that I haven't checked yet

[RobSun]

Pumped swopped. The old one wasn't too bad but decided to do it anyway on the theory that the water pump was ok other than rusty vanes and that cured the circulation so the worst that can happen is nothing.

I did find a slight leak after the pump. One of the spring clips was a bit loose and there was petrol seeping so that was sorted with a new jubilee clip.

I haven't used it on the road yet but it started first time ran it up to temp for a while and turned off and left it for a few minutes. It started but took a few cranks. Ran it again and stopped and retarted immediately and it fired up straight away. That's looking a little better but I now need to road test it but I have to wait in for some deliveries today and tomorrow, and the MOT runs out. The classic friendly garage I used has just sold up to a property developer so need to book it in elsewhere.

On the electronic ignition and coil, I spoke on the phone to the classic restorer who fitted mine for me, and he said that if it was the unit the car wouldn't start full stop, with the one fitted. He then said that it could be the coil or quite possible the alternator putting out high voltage when hot and the electronic ignition doesn't like this. This he says isn't uncommon and the symptoms are refusing to start when hot and missing at speed. Now that sounds a bit familiar. He said the only way to find out is to check the voltage when hot and the car not starting. If it is high an extra wire has to be run in and a resistor fitted to cure it.

Next coil questions. I looked on line (Rimmers) at coils to get ideas on prices types etc. if one was needed. They had two a 12v sports coil with threaded low tension terminals and a 6v standard coil for use with a ballast resistor. This had spade connectors and looks exactly the same as that fitted but I cant find any markings on mine. How do I know what 's fitted and needed? The guy who fitted the ignition didn't swop the coil and Toledo Man says some kits work only with 12v and others will work with the 6v coil. The electronic unit fitted is all within the distributor. I cant remember what make it is.

I will let you know when its been on the road, probably to get tested.

Jonners if you read this I have PMd you regarding an add you had a while ago.

Bob

[RobSun]

Update

Gave it a test drive this pm. Ran ok got it up to temp. and then stopped the engine and left it for 5 mins and it restarted first time, so I took it out again straight away. This time it would not start so I checked the coil and it was red hot. Thanks for that tip Mantney. Let it cool down and it started ok so went home where I had a repeat performance but this time the engine stopped itself just outside the garage.

I have given the coil a look over and in scraped off print caused by the bracket I found ?V Ballast Coil it could be a 2 or a 6, and 09-202 or 206 or similar as its almost totally rubbed off.

Has anyone any ideas which coil I need.

Thanks Bob

[Toledo Man]

I forgot to mention that we also discussed running a bypass for the inlet manifold. I've had a look at the parts catalogues and all the inlet manifolds have coolant running through them. I've checked my Toledo and 1500fwd parts catalogues and they're basically the same. Staying on the subject of the 1500fwd, the part number for the carburettor heat shield is 311967 and it is sandwiched between the carb mount and the carb. Adapting a twin carb heat shield still might be an option.

[mantney]

My 1500 fwd has a heat shield for the carb.

Please let me explain something first off. I had a Manta for a few years which I found hard to cope with due to my limited knowledge. I got rid of that and have gone back to basics with an A35. I also have the Triumph which I'm probably pushing my luck with technically speaking. I'm whittering on here, I know, but the reason is that I don't want anyone to think I'm trying to teach them to 'suck eggs'.
I've only been using the forum since last week so please forgive me as I don't know the back story of your car and what you have and haven't done with it other than what's on this thread.

It could well be vaporisation but I agree with a previous commentator that it sounds more like an electronic / ignition related issue. If the coil is getting red hot it may be breaking down. This could be caused by it just being knackered or by a root cause such as incorrect spark plug gaps. Or possibly, as your man says, too much voltage from the alternator. Or the ballast missing or not connected (if the coil requires one).
I realise there is a lot of or's in there but if you swap the coil and it works you could end up with the same problem again in a short period of time.

Would your electronic ignition manufacturer be able to advise what coil is required?

[Toledo Man]

I mentioned this to Bob. Some electronic ignitions need an uprated coil. According to my post-'76 parts catalogue, the entire Dolomite range uses the same 6v coil. It might be worth getting an uprated coil and seeing if that cures the problem.

[mahony]

check with the manufacturer of you electronic ignition system to find out what coil they reccomend , some electronic ignition systems do not like sports coils as the ohms are to high, see this topic viewtopic.php?f=4&t=25097&hilit=sports+coil

[RobSun]

I had come to the conclusion that it is the coil. I've done a bit more digging and 90% sure the coil fitted is from Rimmers and they describe it as a standard 6 volt coil but the picture shows 12v ballasted on the printing. This would appear to be what was on my coil before some of it was rubbed off.

Just been to check if I can find the ballast resistor on the car and I can't. The white wire to the positive terminal on the coil comes out of the loom near the coil and has been sleeved so I am assuming that it was removed when the electronic kit was fitted. Again I am assuming the resistor would have been fitted on the inner wing according to the description in Haynes. I have gone through the wiring and there has been some mods to it but I can't see anything between the solenoid and coil that looks like the resistor.

Not knowing what's fitted I can't even consider what coil I need so I am going to go and visit the guy who fitted it now. I asked him on the phone about the coil the other day and he said he thought it was 12v and OK for the kit fitted but now I'm not convinced. I also want to know if he removed the resistor and if so is a non ballasted or ballasted coil needed.

Had to cancell the mot for today now.

Thanks for all the help everybody.

[Toledo Man]

The ballast resistor is incorporated in the wiring loom.

[Jon Tilson]

I got so fed up with typing the same stuff about this I wrote this...

https://dollywiki.co.uk/wiki/Ignition_b ... ss_removal

Have a read and it explains things.

What you need is a ballasted coil as OE and to feed the power for your module from a 12V supply.

What may have happened in the past is that someone has wired the 6V coil direct from 12V supply, which is why it is running far too hot and cutting out.

To see what's what you need a cheap multimeter able to tell the difference between 6V and 12V (nominal of course - we all know a lead acid battery is 13.2 V at ISA and will charge slightly higher if the alternator is working as it should)

There is a convenient 12V switched supply at the fuse box...white wire unfused side.

Sorry no PM as yet.

Jonners

[RobSun]

I've just posted and it all disappeared.

Dave I have looked for the ballast resistor, Haynes say it is an easy job its located adjacent to the coil on the left side of the engine bay on the valance and states there are white and white/yellow wires to it. I have a white wire going to the coil and yellow wires also. I assume these were originally to the resistor.

Jonners thanks for that post. I have just got back from the guy who fitted my unit. Having read what you say there is a wire from the fuse box to the distributor then back to the coil and I am sure the resistor is missing. I suspect from my asumtions and your post that this is a 6v coil with 12v running through it now.

Chris who fitted it says it needs a new coil but also thinks to high a voltage is going through it. When he fits them, its a luminition unit, he checks voltages etc and fits coils and ballasts as required. He suggested I get a luminition coil and ballast balanced for the system, which I have done from moss bros. He then said that electronic ignitions are optimised at 9v and if to much power goes through hot start again can be a problem, but then if this set up optimisers the system I may get cold start problems which he was seen a few times on mgbs. To overcome this he says you need to run a wire from the starter using relays. I have decided to let him do it, but he's busy finishing a tr6 that has to be on a ferry to Spain next Saturday so it will be done in about 2 weeks.

I'm not a thickie but sometimes this old brain takes a bit longer for info to register and nothing works better now than hands on but I just didn't feel confident enough to carry on with the electrics. Having read your post and what he was saying I think I understand more but I have a slight suspision that someone may now be baffling me with science.

[Jon Tilson]

Remind me what year and model this dolomite is?

I think but am not certain that ohv cars also had a ballast resistor in the loom as Dave (Toledo man) said.
In earlier cars there was indeed a separate ceramic ballast resistor. On ohc dolomites this was mounted with the coil on
the inlet manifold.

It really isn't that complicated. You just need a simple multi-meter and know where to put it. I am happy to
talk you through the process on a mobile if you need. You dont want to wait two weeks for something that can be fixed
in half an hour.

You can also send me pics of the wiring if you have a suitable phone.

Lumenitions will trigger just at 6V but misfire at higher revs. You need 12V to make them reliable on the supply side.

PM me for number exchange. We can sort this....


Jonners

[Toledo Man]

It is a late Dolomite 1300. Hopefully, the wiring diagram from the factory workshop manual should help.

[Jon Tilson]

Coil here...

http://www.ebay.co.uk/itm/12-Volt-Cold- ... 2edfa4ad03

but be quick.

[Toledo Man]

Bidding has just ended at £21.50

Rimmer Bros sell a standard coil for £18. Their high performance one is £27 The prices include VAT but postage will be extra.