18 replies to this topic

[tiger99]

As Doug says, check the timing. Check also the state of the thin pipe for the vacuum advance, the rubber bits at the ends often split, and check for sideways play in the distributor shaft. If there is much, you will need a reconditioned distributor, worn bearings don't allow for a stable points gap or consistent timing.

And, check the oil in the carburettor dashpot. Just unscrew the nut on top, with fingers (it is plastic on all but the earliest models) and pull out the plunger. There should be clean oil in there, almost up to the top of the inner tube. It should be special SU damper oil, or SAE 30 (not multigrade), but others use 3 in 1. If you overfill it, no harm is done, the excess will leak via the tiny gap between the inner and outer tubes and be burnt by the engine.

Before you do that, if feeling adventurous, you could have the complete upper part of the carburettor off, and check that the piston is moving freely. Beware of bending the needle. You could also remove any muck in the float chamber, fit a new needle valve and float, generally give it a good clean, and re-centre the jet, all as per Haynes.

None of this is expensive, except the distributor. Fortunately the Lucas ones don't usually wear, but if you are unfortunate and have a Ducellier they are a right pain.

[Andy.]

Hi mate , after checking all the stuff like oil in the dash pots and dirt in the carb etc ,Call a mobile engine tuning man to come and set it up,he will sort it in less than an hour he will replace the bits that need to be replaced and tell you the bits that are worn,you may have to call a few to find one that is experianced with cars that have points and carbs and nowhere to plug a laptop in to tell them what to do, Last time I got my midget done after she threw a wobbely and would only start if she felt like it and not at 3am when I am on early thank you very much! . I Don't know what he did and I don't care he just did his stuff, it cost me forty quid he ballenced both carbs one of them was worn and I had a stiking float in the float chamber . I saved more than forty quid in fuel alone never mind the cost of replacing differaint parts to solve a problem

[Benjy25]

I'm starting to run out of ideas
Anyone near Chingford / Walthamstow fancy coming to help a rookie mechanic ?
Ben

[petey81]

hi mate ive had same problem
I blew through float bowl into main jet to check for block
I also had a kink on the tube going from float bowl to main jet
I checked overflow pipe and breather
cleaned dashpot and replaced spring
I also checked float bowl needle and valve for wear and sticking.
hope this helps.