It dribbles...

[Andrew Craig-Bennett]

The "subject" is a bronze flywheel Forty Plus. It is a very good little engine, but it is inclined to drip petroil slowly, when laid flat, even on those occasions when I have remembered to stop it by closing the fuel tap and have shut the tank breather.

Is anything to be done?

I am worried by the thought of an inadvertent conflagration!

[charlesp]

When laid flat they do dribble - mostly out of the carburettor, which is probably a Villiers. You'll notice a small hole in the float chamber body. It from this orifice that your dribbling emanates.

The suggested 'fix' is to close the fuel tap and let the motor run until the fuel in the carburettor has all been used. It's not a bad idea to keep to this regime even if the motor will remain vertical - any fuel remaining in the carburettor may lose the petrol component to evaporation and contain only oil. This makes starting difficult

[headcase]

If your carb is fitted with the plastic float chamber you could unscrew it and pour the petrol back into the fuel tank. This also gives you the oppurtunity to wipe out the debris that seems to gather there...

[Andrew Craig-Bennett]

Yes, it's a Villiers carburettor. I always do stop it by running it dry, but I still get the odd dribble. Perhaps "dry" is not really "dry". I was suspecting the tank filler.

[Ian Malcolm]

There is (or used to be) a tank service kit consisting of new sealing washers for the cap and the vent and a new retaning spring for the cap. John may well be able to supply the sealing washers at least.
I prefer to transport a filled seagull flat with the carb up. Unless the tank is over-filled this will put the filler above the fuel level but I still tighten the cap and vent firmly. As to the few cc of fuel left in the bowl after running the carb dry, I usually tip that out onto some paper towel and wipe the excess oil off the leg before putting it in the boot.

Its possible you have a slightly leaky tap in need of a new cork. It would be worth taking the fuel line off and checking if the tap is weeping slightly. While you are there, clean the crud out of the fuel line

The other possiibility for an unexplained leak is a hairline crack in the tank itself which sometimes happens around the mounting studs. It may be so short and narrow that it doesn't actually weep a noticiable amount of fuel untill the tank is stressed by lieing the engine on it :-(I

[Andrew Craig-Bennett]

Thanks, Ian.

I suspect the tank washers, and will also look hard at the petrol tap, then contact John.

Meanwhile, will try "carb uppermost" transport!