Hi all,

I just want to know if this is normal, and if so how to stop it maybe?

If i use my Favorit (carbed) everyday then it starts well after a second or 2 cranking and runs ok (if a little rich). But if i leave it more than a day, say up to 3 days, it requires a lot of cranking to start.. If i leave it more than 3 days i need to pump fuel by hand (from the little lever on the fuel pump) to the carb till it fills then it starts immediatly.

So it seems that fuel is evaporating/leaking from my carb somewhere. There are no leaks when its running (and fuel pressure is highest) so i cannot think whats happening, maybe it is simply evaporating through the air filter? but no other carbed vehicles did this.

Does anyone else have the same thing or any ideas to where my fuel is going?

Thanks

Courior

Could it be flooding the engine, causing difficult starting after 3 days?

its just evaperation, does your fuel pump have a manual lift lever on it to prime it? could just use that to prime it if its been stood for a few days to save cranking for so long.

Check for a loss of priming between pump and tank...ie air leak at fuel pipe connections, etc...or perished fuel pipe.

Simple solution is to bypass the mechanical fuel pump using an electric fuel pump [wired into the ignition circuit]....thus, when the ign. is turned on, the pump will prime the carb.

Certainly your existing mechanical pump seems weak if simply turning the engine over a few times doesn't result in fuel at the carb.

Heat from the engine can result in fuel in the carb's float chamber cooking off.....one reason why there is a vent on it...a good condiditon mechanical pump should prime the carb quickly....I suggest trying as above , or replace existing pump, and check fuel line connections..[can be loose enough to allow air in [losing priming] yet not allow fuel to leak out.

Also check fuel cap on tank..in case a vacuum is being created in the tank..

Edited 8 December, 201114 yr by alastairq