Fuel leak

[howardmoon]

Hi guys,

I need a bit of advice. I started my bike after a week or two of it sitting idle and had given the battery a charge. Bike starts no problem. There is a fuel leak, fuel runs down the back of the engine but I can't see from exactly where. After a few more checks I have found the fuel leak starts when I switch on the ignition and the fuel pump is priming. Then it stops. When I fire the engine the leak starts again. With the engine running it sounds rough, like it is not running on all 4 cylinders.
My suspicion is a stuck float bowl in one of the carbs. Is there a trick I can do to fix this without having to remove the tank and airbox just to get access to the carbs?

Thanks and happy xmas to everyone

Paul

[Falcon 269]

Could be a stuck float but also consider this:

http://www.yamahafz1oa.com/forum/showthr...ilure+mode

A stuck float can usually be sorted by tapping the float bowl gently.  Wooden hammer handle or similar - don't use the other end!

[red98]

Hi paul......yep, I think you might be right, sticking float in one of the carbs causing the excess fuel to exit via one of the overflow tubes that run down the back of the engine....theres allsorts of carb cleaning additives you could add to the fuel which might solve the problem , not used them myself as not a fan, if that was mine I would remove the carbs and give them a good strip and clean.....just my view and iam sure someond else will be along shortly with another solution...

[howardmoon]

Hi Mike,

The fault has gone away.I ran the bike with the tank removed, it ran for a few minutes before all the fuel in the pump and lines was used up. I refitted the tank , connected everything up and it now runs leak free........and sounds like all 4 pots are in use.
I guess what ever was blocking whatever was blocked has been sucked through.
It this happens again I'll whip the carbs off but it seems OK now.

Cheers, Paul 

[Falcon 269]

Sounds like it's sorted - excellent.  Another way of doing the same without having to remove the tank is to simply drain each float bowl using the drain screw.  Just be careful re-tightening the screw because it's easy to crack the float bowl if you overdo it.