My M750 Rebuild

utopia · 06-04-2018, 06:05 PM

Well, my instinct says that if fuel is flowing from the floatbowl overflow pipe then the float valve has to be leaking, despite your previous cleaning.
The only other thing I can think of is that you have some pipes connected up wrongly and the fuel is actually flowing from somewhere else.
Both seem unlikely but maybe not impossible.
In the latter case, this could perhaps be compounded by a perished diaphragm in the fuel tap, causing it to remain open ... which would not be surprising after 7 yrs as rumour has it that they don't like drying out.

All the above is a tad tenuous though.
Does fuel flow from the overflow when the engine isn't running ?

06-04-2018, 06:05 PM	#28
utopia No turn left unstoned Join Date: Jun 2010 Location: leicester Bike: M750 Posts: 4,545	Well, my instinct says that if fuel is flowing from the floatbowl overflow pipe then the float valve has to be leaking, despite your previous cleaning. The only other thing I can think of is that you have some pipes connected up wrongly and the fuel is actually flowing from somewhere else. Both seem unlikely but maybe not impossible. In the latter case, this could perhaps be compounded by a perished diaphragm in the fuel tap, causing it to remain open ... which would not be surprising after 7 yrs as rumour has it that they don't like drying out. All the above is a tad tenuous though. Does fuel flow from the overflow when the engine isn't running ?