Hot start problem - 1953 Series II

[ROTR]

I have had a problem a couple of times recently and wonder if anyone has ideas on what might cause/ solve it. On a hot day after a 20 mile or so run I stop (to fill up or call in somewhere) for about 10 minutes. The car will not restart. It is pretty hot under the bonnet and I have to wait for 20 minutes or so to let things cool down. It will then start normally. This has never happened in cooler weather or if my stop is for a longer period in the first place. Is it maybe down to fuel vaporisation? I have an in line fuel filter between the pump and the carb which seems not to be filling up as much as it does under normal running.

[oliver90owner]

Probably a fuel:air ratio issue but rudimentary checks needed doing before posting.

Check for a good strong spark when the issue arises. A simple check to avoid hunting for fuel issues if it is really an electrical one.

Check plugs for whether running rich, weak or OK.

Are routine service items within specification?

The fuel level in the carb should not change at a short stop, so the engine should fire - even if it then becomes starved of fuel due to volatilisation.

The fuel filter between pump and carb is not standard. It may be part of the problem and is also an unnecessary extra item to potentially give problems.

[les]

Replace the condenser in the distributor, that could be the problem.

[ROTR]

Interesting. The first time it happend I looked at the electrical side first. There seemed to be no spark at the plug so I checked again and the second time it was good. The plugs are good quality and new and the colour is as expected - very slightly on the rich side. All routine servicing has been done and everything seems to be within spec. The electronic ignition seems fine. I did remove the HT lead to the coil (which is only a couple of months old) and reseated it on each occasion and I wonder if the coil itself may be faulty at higher temperatures? I've got a new Lucas one in my spares box so maybe I should replace the coil. Does that seem like a good plan?

[myoldjalopy]

Quite honestly, if you suspect the coil and have a spare, it won't take long at all to swap over and see if that makes a difference. Even if the current one is 'only a couple of months old', there have been problems with poor quality 'modern' coils on this forum. If you swap the coil it will, at least, prove or disprove your theory, assuming the 'new Lucas one' is any good. Personally, I favour good, old 'proper job' coils and have two - one fitted in the car's ignition system and one in my spares box.

[ROTR]

Point taken! Only hesitation I have is that I can't figure out whether the coil clamp has captive nuts. It's fitted to the bulkhead and I don't seem to be able to get into the cavity to check. Guess I'll just have to take my chances. Hopefully the spare coil is a good one - it came from ESM.

[MM1949]

Originally the coil was mounted on the bulkhead with nuts, bolts and washers...so a bit tricky to remove/mount...

[myoldjalopy]

Like you, my car has the coil mounted on the bulkhead but I have swapped it out in the past with no great difficulty. I can't remember if there are captive bolts but I doubt it. You should be able to get to any nuts and washers behind the parcel shelf, or maybe you will have to remove a glove box liner. I can't remember it was so long ago now but don't think it will be anything worse than a bit fiddly to do.

[ROTR]

Thanks everyone. The bolts have non captive nuts accessible from just above the parcel shelf and I've managed to fit the new unit without any real trouble. Once it was off I could see that the centre HT socket on the old unit was pretty cruddy so there must be a chance that was the source of my problems. I'll just have to wait and see!

p.s. To cheer me up a bit I found that some wag had let down my front tyres overnight and now I'll have to go to the fitters because I haven't the strength, equipment or skill to reseat the beads so that the tubes can be re-inflated. Such fun!