ignition works fine when engine cold then no spark when warmed up?? help!

[contessaman]

Probably best to replace the battery, carburettor, engine and gearbox, too, just to be sure! ;-)

come to think of it the boat is getting a bit long in the tooth too!

To the poster who says about relocating the electrical gubbins - that would be nice but im afraid that cant be done as it needs to be next to the rotating shaft inside the distributor for it to work. if you click the link earlier in the thread to the unit you see what I mean.

However those who have suggested some cooling spray thats a REALLY good idea as I can cool specific parts one at a time which should really aid diagnosis! thankyou I shall buy some!

 

[contessaman]

I meant as a fault-finding exercise, to prove it is the red box.

its a good idea nige but as we replaced them when they were burned out we did not keep them. cant bring ourselves to buy anothe set for diagnosis just yet. Just found somewhere selling the electronic units at £28 inc p&p so it will be as cheap as anything else to just try a new one of those.

I put my ohm meter across the new and old coil when hot and got circa 3 ohms which is about right so I dont think there is a problem in the LT side of things. we also had a spare coil in the gargage which we tried to no effect so I think the chances of 3 coils being faulty is pretty low.

 

[RichardS]

Unlikely to be distributor cap or HT leads. I would be surprised if these would fail so predictably simply because of a heating effect.

I replaced the points on my Carlton many years ago with an after-market CDI unit from Halfords. It ran perfectly for about 6 months and then started misfiring when warm. I replaced the rotor arm and points as a test and it ran perfectly. Took the control box back to Halfords who replaced it FOC. After that the car was fine.

Richard

 

[TWINSCREW]

I would look at the distributor, what happens is that after a short while running, because of the heat, condensation forms inside the cap and leads to "tracking" of the spark, old Fords were noted for it, next time it happens look inside the cap and you may find it wet, and the reason it starts later is because the cap has dried out. a spray of WD40 when completely dry and wait for the WD to dry before use may cure your problem.

 

[nigelmercier]

I would look at the distributor... a spray of WD40 when completely dry...

I remember when a can of WD-40 was mandatory for BMC Mini owners; the distributor was directly behind the grille.