Gas Pouring Out of Fuel Filter

[SpongeBobbed]

Hi Guys,

I picked up another 650 a few weeks ago and have been trying to turn it into a bit of a cafe racer. I've been working on a bobber on and off for the last couple years, so I wanted something I could just ride and add a few things here and there. It was a pretty sad sight when I first picked it up, but I've added a bunch of stuff and have it looking like this now:

Painted the front forks, put the boots and the fairing on, new handle bars, LED signals and taillight, seat, side covers, shocks, pipes, re-did some of the electrical, etc. I wanted this bike to have all bolt on parts for now. I spend tons of time with my other one, so I wanted to keep this relatively simple.

When I picked it up of the PO it was running like crap. Only firing on one cylinder, wouldn't idle, etc. I narrowed it down to a carb issue, and promptly rebuilt the stock BS34s that were on the bike. Bumped the pilots and mains up one size from stock, put the Canadian needles in, new gaskets, etc. Cleaned these things as much as possible. Synched the carbs and it fired right up and ran smoothly through all RPMs. Rode it around for a while and then started noticing a gas puddle under the bike when I was idling it. I looked closer and there is gas pouring out of the new in-line fuel filter I put in. It also seems to be flooding and the bike instantly quits when I put the choke on. I took the carbs off and inspected the lines/fuel filter but nothing looks out of place.

Note that the bike originally had a vacuum petcock on it but I installed a new non-vacuum type. I also installed the rubber plugs for the vacuum barbs on the carbs.

Has this ever happened to anyone? Any advice would be greatly appreciated!!

Here's a video of it running prior to all my gas pouring out of the fuel filter. Still needs some more tuning but it's a start. Cheers!

 

[nonXSive]

I've had the same problem a couple times.
On mine, small debris (rust from tank) gets into a carb and makes the needle stick open which keeps the float down and floods the carb and fuel drains out the air filter and into the engine.

I've pulled the carbs out and cleaned them but still need to clean the tank (CLR method), get a better fuel filter and change the oil.

Gas in the oil will eat up the crank bearings over time from what I've read on here.

 

[ANLAF]

Spongebobbed, I rebuilt my carbs last year, and made an error fitting the float needle into the cylinder - result, the needle stuck in position causing, you've guessed, a stream of fuel. It will be something simple. I take it you have read the carb guide, if not, have a flip through. Something stuck, something worn, something not put back properly, something nor set quite right. Likely to be one of these things - if you can, take off your filters, and with the engine running raise the throttle arm while looking in the back of the carbs (or get a finger in there if you can't see. Both cylinders should rise and fall in a similar way, if not you may be on the track to finding the problem.

Good luck.

ANLAF

 

[SpongeBobbed]

Thanks guys. I'll pull them back apart and see what I can do. The gas is leaking out of the in-line fuel filter before it even gets to the carbs, but with the bike dying when the choke gets pulled that's a clear sign that it's being flooded. So far no fuel is getting into the air filters behind the carbs.

I did just take a quick look at them and realized that the right cylinder is falling at a slower speed than the left. The both go back down, but the right is definitely slower. Maybe that has something to do with it.

I'll keep looking!

 

[jayel]

sounds like a crack in the fuel filter it self, replace it

 

[SpongeBobbed]

Jayel - I think you're right. I can't think of anything else that would cause gas to be coming directly out of the in-line filter. It's brand new and it's oriented the right way, so I just didn't think that would be the case. I'm going to take it right off and see if the bike runs fine with out. If so then that was the issue and I'll pick up another one.
Thanks!

 

[SpongeBobbed]

So it was just the fuel filter. There was a hairline crack in it that was causing it to leak. Took it off and no more gas leaks. Went for a 200 mile ride and found about 4 new things that need fixing. It never ends, haha