Gas cap leak too much?

bigheavy150 · 01-13-2011, 09:44 PM

When i got the italika it leaked alot of fuel out the gascap vent.On the underside of the cap there is 3 screws and a big hump. remove the screws and under the hump there was 2 steel balls one big one small. Check valves. Usually there is only 1 so i took the small ball out and re assembled. No more leaks,not a drop. i was able to take the hose thingy off too.

I wonder why they put 2? it really didnt work at all as a check valve. I probably lost a few CUPS worth of gas per tank through it.

mizke · 01-13-2011, 10:48 PM

youre gas needs to breath, as the motor pulls gas out of the tank it creates a suction. if you cap the intake end of the suction, eventually the motor will wont be able to pull any gas out.. try and find a vented gas cap locally and then on ebay.. it will have a small hose with a little cnc aluminum one way valve on top of the vent hose.

bigheavy150 · 01-14-2011, 04:42 PM

Quote:

Originally Posted by mizke

youre gas needs to breath, as the motor pulls gas out of the tank it creates a suction. if you cap the intake end of the suction, eventually the motor will wont be able to pull any gas out.. try and find a vented gas cap locally and then on ebay.. it will have a small hose with a little cnc aluminum one way valve on top of the vent hose.

It does breath air in both directions, but not fuel

. the steel balls are checkvalves that let air pas but not fuel.
But having 2 balls in one hole makes it just a open hole that squirts gas. I should have posted pics. I have no clue why they had 2 steel balls in there, one was about 1/2inch and the other was just bigger then a BB. I took the small one out.

Idk it just bugged me that i had a constant stream of gas running down my new frame/engine.Damn old timey cobble stone streets shake the **** out of everything. Now if i can just get the carb to stop pissing.

01-13-2011, 09:44 PM	#1
bigheavy150 Join Date: Jan 2011 Posts: 119	Gas cap leak too much? When i got the italika it leaked alot of fuel out the gascap vent.On the underside of the cap there is 3 screws and a big hump. remove the screws and under the hump there was 2 steel balls one big one small. Check valves. Usually there is only 1 so i took the small ball out and re assembled. No more leaks,not a drop. i was able to take the hose thingy off too. I wonder why they put 2? it really didnt work at all as a check valve. I probably lost a few CUPS worth of gas per tank through it.
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01-13-2011, 10:48 PM	#2
mizke Join Date: Aug 2010 Location: austin, tx Posts: 1,452	youre gas needs to breath, as the motor pulls gas out of the tank it creates a suction. if you cap the intake end of the suction, eventually the motor will wont be able to pull any gas out.. try and find a vented gas cap locally and then on ebay.. it will have a small hose with a little cnc aluminum one way valve on top of the vent hose. __________________ 200cc beast replica,carsoli cdi,performance coil,fmf powercore 2,uni air filter,hour/tach meter,jetted mikuni carb,msr bars,moose racing grips,yz250f clutch perch,D.I.D chain
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