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From: nomorespameventhoughthejapanesespamgivesmeachuckle on 1 Jul 2006 15:20 I just recently noticed a gas leak on my bike. I first noticed it dripping from my left-most carb (#1). It was leaking from many different locations that it should *not* be leaking through because of gaskets (like the float bowl seam). It then started leaking from the overflow on the crab. Well, I took the gas tank off and found out that the petcock leaks. I drained it and took apart the petcock and while everything *looked* normal, I placed an order for a petcock rebuild kit (which will be here on July 5th because of the holiday). Anyways, I played around with the petcock last night by lightly pushing down on the diaphragm with a flat-blade screwdriver. I reassembled the petcock and no leaks for hours. I rode it around last night and parked it for the night. I awoke in the morning to crab #1 flooded again. I unhooked the gas tank lines and the petcock was leaking again. Now my question: Do I likely have a problem with just the petcock leaking or with a carb too. I find it odd that only carb #1 leaks... but this may be due to the fact that when I put the bike on the side stand that the lean causes that carb to leak. By the way, I did rebuild carb #1 with a new valve seat and valve needle after this happened the first time last week because the needle was slightly worn; but this didn't seem to help. Could I have a bad float in that carb? Thanks!
From: FB on 1 Jul 2006 16:25 nomorespameventhoughthejapanesespamgivesmeachuckle wrote: > It then started leaking from the > overflow on the crab It's not so bad when your crabs overflow. A little bit of mayonnaise mixed with cooked shredded crab meat makes a nice sandwich. Seriously, though, your float valve is either sticking or there is trash on the float valve seat on that one carburetor. You might try squirting some Berryman's B-12 down the fuel line to dissolve whatever gum and varnish might be keepingthe float valve from sealing properly.
From: nomorespameventhoughthejapanesespamgivesmeachuckle on 1 Jul 2006 17:50 FB wrote: > nomorespameventhoughthejapanesespamgivesmeachuckle wrote: > > It then started leaking from the > > overflow on the crab > > It's not so bad when your crabs overflow. A little bit of mayonnaise > mixed with cooked shredded crab meat makes a nice sandwich. > > Seriously, though, your float valve is either sticking or there is > trash on the float valve seat on that one carburetor. You might try > squirting some Berryman's B-12 down the fuel line to dissolve whatever > gum and varnish might be keepingthe float valve from sealing properly. But... I changed out the seat and the needle with known good ones out of a rebuild kit and the problem still persists. Do you disagree that there is definitely a problem with the petcock that it keeps leaking -drip drip drip- when it's in the ON or RES position (it's vacuum operated). I stored the tank for the entire winter with Stabil in it and it never leaked once. I'm wondering if the petcock was the original problem or if that became a problem because of another (i.e. pressure built up and the gas had to go somewhere so it put a small hole or tear in the diaphragm). I say this because I was watching the problem persist as I was working on the bike and the leak started at the carb and it wasn't until an hour later that a leak started to develop from the petcock (not saying the petcock wasn't *leaking* then it's just that the pressure built up so much that with the tank attached gas was coming out of the seals and overflow screw on the petcock.) Thanks! =) Yeah spell check doesn't catch that but proofreading should... Guess I should learn to proofread.
From: FB on 1 Jul 2006 22:46 nomorespameventhoughthejapanesespamgivesmeachuckle wrote: > But... I changed out the seat and the needle with known good ones out > of a rebuild kit and the problem still persists. Do you disagree that > there is definitely a problem with the petcock that it keeps leaking > -drip drip drip- when it's in the ON or RES position (it's vacuum > operated). Yes, you might have a problem with the petcock diaphragm, the automatic valve operated by the diaphragm, the spring that pushes the valve shut, or you might have a bad grommet in the selector side of the petcock which allows fuel to leak from the PRI side to the ON port. The float in the left carb may be set too high, the needle valve could be leaking, and there could be trash on the float valve seat that has accumulated there since you installed the new seat. > I'm wondering if the petcock was the > original problem or if that became a problem because of another (i.e. > pressure built up and the gas had to go somewhere so it put a small > hole or tear in the diaphragm). There just isn't that much fuel pressure in a gravity feed system where the highest point in the gasoline level is maybe 12 inches above the float valve. Gasoline has less than half the specific gravity of water, so the pressure is maybe 1/4 of a pound at the float valve. That's why the tiny little float has enough bouyancy to close the float valve. > I say this because I was watching the > problem persist as I was working on the bike and the leak started at > the carb and it wasn't until an hour later that a leak started to > develop from the petcock (not saying the petcock wasn't *leaking* then > it's just that the pressure built up so much that with the tank > attached gas was coming out of the seals and overflow screw on the > petcock.) It's not the pressure, as I said above, but gasoline is thinner than water, so it weeps pasts gaskets and goes through tiny gaps in rubber parts easily.
From: nomorespameventhoughthejapanesespamgivesmeachuckle on 6 Jul 2006 23:36
FB wrote: > nomorespameventhoughthejapanesespamgivesmeachuckle wrote: > > > But... I changed out the seat and the needle with known good ones out > > of a rebuild kit and the problem still persists. Do you disagree that > > there is definitely a problem with the petcock that it keeps leaking > > -drip drip drip- when it's in the ON or RES position (it's vacuum > > operated). > > Yes, you might have a problem with the petcock diaphragm, the automatic > valve operated by the diaphragm, the spring that pushes the valve shut, > or you might have a bad grommet in the selector side of the petcock > which allows fuel to leak from the PRI side to the ON port. > > The float in the left carb may be set too high, the needle valve could > be leaking, and there could be trash on the float valve seat that has > accumulated there since you installed the new seat. > > > I'm wondering if the petcock was the > > original problem or if that became a problem because of another (i.e. > > pressure built up and the gas had to go somewhere so it put a small > > hole or tear in the diaphragm). > > There just isn't that much fuel pressure in a gravity feed system where > the highest point in the gasoline level is maybe 12 inches above the > float valve. Gasoline has less than half the specific gravity of water, > so the pressure is maybe 1/4 of a pound at the float valve. That's why > the tiny little float has enough bouyancy to close the float valve. > > > I say this because I was watching the > > problem persist as I was working on the bike and the leak started at > > the carb and it wasn't until an hour later that a leak started to > > develop from the petcock (not saying the petcock wasn't *leaking* then > > it's just that the pressure built up so much that with the tank > > attached gas was coming out of the seals and overflow screw on the > > petcock.) > > It's not the pressure, as I said above, but gasoline is thinner than > water, so it weeps pasts gaskets and goes through tiny gaps in rubber > parts easily. If it's not pressure, then why does gas not weep through gaskets when the carbs are presumably flooded? The parts that the gas is weeping through are exposed to gas even when the carbs are not flooded, though they weep not then. Thanks for you help! (Also if you don't mind, privately - or openly, your choice - mail me how the carbs on my bike work because it seems I might not understand them correctly.) nousenetspam<removethis>@gmail.com |