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MG MGB Technical - Still Have a Slight Fuel Smell

After replacing the rear float and re-adjusting the carbs, I still have a faint fuel smell after idling (at a stop, etc.). The float replacement was required due to a major flooding condition that resulted in fuel discharge through the evap canister overflow.
Have changed the oil - no indiction of fuel getting into that area. Don't see any other indication of leaks or flooding.
Is it possible that the odor is remaining in the evap canister? Good idea to replace the charcoal? The entire canister?

Thanks for any ideas,
Pat
'73BGT
Pat

I suppose it's possible, although if all the plumbing is intact I can't see where you'd smell fuel. Are you sure it's coming from under the bonnet and not the boot? A cracked hose at the vapor recovery can in the boot will cause a faint fuel smell in the cockpit.
The charcoal can be replaced with aquarium type from a pet store or dept. store that handles pet supplies or if you have a spare cannister you could swap it out.

Mike
'79B
Mike Janacek

If you have an SU pump (clicks initially then only as fuel is used) you can check the float valves (and for other leaks) by leaving the ignition on but not starting the engine. After any initial flurry of clicks it should not click more than once every 30 secs. More than this indicates a leak, or possibly a bad non-return valve in the pump. This latter won't cause smells, but possibly fuel starvation at large throttle openings when the valve gets bad enough.

A flooded cannister will take time to clear, but if all the emissions hoses are sound and not blocked you shouldn't get any fuel smell when the engine is running anyway, as the crankcase breathing system is drawing fresh air through it.

The top of the tank having rotted through will also cause smells, more prominently at the rear of course, and more so with a full tank. You may also see dark staining down the sides of the tank.
Paul Hunt

Mike & Paul,
Thanks - all good info. Guess I will have to start eliminating one thing at a time. Don't recall noticing any odor until after the carb flooding problem that I had. That resulted in a significant amount of fuel pumping through the canister (which is why my first reaction was to suspect that as the cause).
Smell seems to occur after idling (I don't even notice it while stopped) - get a small dose of odor just as I begin to accelerate from a stop. Also a small trace after turning the engine off.
I'll try to work my way through your suggestions, one at a time.
Thanks again,
Pat
Pat

You may well just be smelling the fuel residue on the greasy engine ? . or perhaps if was really flooding badly the oil has been diluted and needs changing - filter too
give the dipstick a sniff to see if it's the oil .

-Nate
Nate

Nate,
Engine compartment is pretty clean, and have replaced both the oil and filter - all with no signs of fuel.
Only seems to happen while idling.

Pat
Pat

This thread was discussed between 05/11/2002 and 07/11/2002

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