Sticking float

[GrahamF]

This will be a common fault I'm sure. I took the car out this evening for the first run in a couple of weeks and the smell of petrol was strong. I checked under the bonnet and saw petrol in the v of the engine block, and fuel dripping below. I have had this once before, so I checked the screw in tops of the carbs, one had resistance, but the other didn't, so I assume this is the problem. How do I release the float, and what causes this to happen, and how can I stop it happening again?

[Ian F]

Graham

Surprised no-one has replied, but here's my thoughts:

Are you talking about the large black plastic screws on top of the carbs? These are only the dampers, that stop the Pistons in the carburettors from rising and falling too quickly. The oil in them "damps" the movement when they are filled with oil.
Lack of resistance in one or other carb could be a damper piston sticking or that one damper has no oil in it, they quite often leak and lose the oil.

The float sticking and flooding of one or more carbs, may still be the problem, but this could be sticking needle valves, incorrectly set floats, dirt or debris blocking the needle valves or one of many other issues. If you have an owners manual then I would check the carb section and review how to strip and rebuild them with new needle valves. This may cure the problem.

Ian F

[markmark2]

This will be a common fault I'm sure. I took the car out this evening for the first run in a couple of weeks and the smell of petrol was strong. I checked under the bonnet and saw petrol in the v of the engine block, and fuel dripping below. I have had this once before, so I checked the screw in tops of the carbs, one had resistance, but the other didn't, so I assume this is the problem. How do I release the float, and what causes this to happen, and how can I stop it happening again?

Hi Graham, I have had the same fault. It has taken me 3 weeks to cure. Im far from an expert but I am a hell of a lot more savy now! For me it was leaking float chamber gaskets, floats were incorrectly set and the needle valve was faulty. Either way carbs have to come off. Good luck. Mark

[Arbman Al]

First and easiest thing to try, is start the engine, pull up the plunger on the inertia cut out switch (cylinder looking thing on the bulk head near the fuse box) this will cut off the fuel pump , and the carbs will run out of petrol.

Push the plunger back down, turn on the ignition again and the sudden rush of petrol can clear any dirt caught in the needle valves.

[GrahamF]

Thanks for the replies gents. It seems all it needed was some oil adding into the dampers solved the problem. There was no sign of oil leaking, but it will now be a regular check on my list.
Running well now.
Graham