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MG MGB Technical - Fuel overflowing

I have a 67 BGT - this morning when I went to start it I turned the key to the first position so that the fuel pump starts to tick until the float chambers are full. This time it carried on ticking - after popping the bonnet I saw that fuel was pumping out of the little overflow type nozzle on the top of the float bowl ... right onto the exhaust. So - I took a different car to work today! I am sure this is a really simple thing - but any thoughts on what it could be and what I need to do? If it's any help, I did the head gasket a week ago so the carb assembly was off - since then when the car warms up, the throttle seems to stick open until I blip it which makes it settle back down to idle again. Could this be related?
Thanks in advance
martin

The needle valve in the fuel float chamber is sticking open and not shutting fuel off when float chamber is full. Could just be a matter of a clean. If not new ones are cheap.

Frank
Frank Amey

...also check the pivots on the floats themselves.

Any out-of-roundness or wear in this are will cause
a major fuel hemorrhage.
Daniel Wong

Related? Probably since you have disturbed things. Disconnect the fuel pump at the connector between the whites in the main and rear looms by the fusebox and run the engine till it runs out of fuel. Reconnect the pump, and the resulting rush of fuel through the wide-open float valves should dislodge any dirt (normally the float valves are either closed or only slightly open). If that clears it all well and good, if not fit new float valves. If it cleared but comes back again change the valves, and if it comes back again you have dirty fuel.
Paul Hunt

Martin, from experience, I cannot overstress the need for you to correct the jets post-haste. Unknown to me, perhaps from dirty fuel ( doubtful, I had a new inline filter set), probably from a failed Grosse jet, I had raw fuel overflowing, washing into the cylinders, and the engine blew. I urge you to just replace the jets, and filter now, and run the car with air cleaners off at startup, to ensure you fixed the problem. Use a srew driver and halogen light to check each carb and be sure neither is spewing raw fuel into the manifold ( which, by the way should be accompanied by rough and stumble running and a belching tailpipe)
vem myers

Martin- Its been a while now....Have you fixed the leak??? Vic
vem myers

Thanks Guys - I'll get onto that tomorrow and let you know what happens.
Martin

This thread was discussed on 08/09/2003

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