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vindy500
19th March 2009, 00:04
So my bike hasnt been starting recently. was leaking a bit of fuel too from somewhere. Today i replaced the plugs, sweet as starts now one of the plugs had a bit of petrol on, hmm ok. now when i start it petrol is actually flowing at a reasonable rate from the sprocket. like the bit where the chain attaches too. looks like its mixes with a bit of oil as well as its a dark colour. why on earth would it be doing that?

awayatc
19th March 2009, 04:24
not an overflow tube from your carb?.....
(float in carb stuck probably and now it overflows from a smal tube/hose attached at bottom of carb.)
Drain you carb bowls (smallish screw bottom bowl) and blow through your fuel line/drain tube and try again...

Ixion
19th March 2009, 07:59
Leaking float valve(s). Or the carb bowl has fallen off .

MSTRS
19th March 2009, 08:10
Likeliest is the floats not working. Pull off the drain hoses from the bowl/s and see if petrol is visibly leaking from the little (brass?) tubes.
Otherwise, petrol has got into your crankcase and thinned the oil so much that it leaks out of the final drive seal. :buggerd:

vindy500
19th March 2009, 11:36
i did notice the clamp around the hose to fuel tap had loosened from taking it on and off so much and it was leaking out of that until i tightened it. but i cant see how that would get petrol inside the engine...

MSTRS
19th March 2009, 11:56
It won't. But if a float or float valve is not doing it's job, then petrol will keep flowing into the carb bowl until one of two things happen...
1. Petrol is voided through the overflow system and tickles out of the hose running from the carb bowl down to around the swingarm pivot. Or behind the front sprocket cover.
2. If the overflow system also fails then petrol just keeps on rising above the bowl and runs through the carb and into the inlet port, where it pools if the valve is closed, or runs through the open valve into the cylinder where it runs down past the piston/rings and into the crankcase. In your case, this is most unlikely, because you would not have been able to start the engine were it so, plus with a cylinder full of liquid, turning the engine over would be impossible.

Racin Jason
26th March 2009, 08:31
Not sure of you bike. But some have the crankcase vent going into the bottom of the airbox, so if the carb is overflowing due to a worn/sticky float valve it can run into the airbox and staight into the crankcase and the sprocket seal is the lowest point for it to run out . a fuel soaked airfilter will make the bike very hard to start.

You should get that fuel out the engine (drain the oil) soon as its not good for the seals. Carbs (or at least bowls) will need to come off and be cleaned/ checked. Also does it have a vacum fuel tap? if so this would also have to be failing to work properly if fuel is still flowing with out engine running. Could be that youve got crap in the fuel tank that has gone through the fuel lines.

vindy500
26th March 2009, 17:40
it doesnt have a vacuum fuel line. i got new oil today to do an oil change, just waiting on a new seal for around that shaft. i actually think it might just be oil coming out of the shaft and the fuel was just coming out of the hose which wasnt clamped on tight enough. well see after i replace that seal :)