Changed the oil today and I found that it was very thin due to gasoline mixed with it. I know why there is gas in the oil, I had a leaky petcock that I have fixed now. My question is, could I have messed something up by running it like this? I didn't run it much but I did rev it up. Thanks
Probably nothing damaged. Would take more gas than a leaky petcock(there's that word again)would provide. You didn't leak a whole tank full did you. Anyway change the oil and filter and forget about it.
Make sure that your carburetor float valves are not leaking. Gas has to go thru the carb to get into the crankcase. If it is hard to start after sitting for awhile and locks up at top dead center when you turn it over then you have leaking needle valves.
Yeah I've been through the whole ordeal with that already. In the process I actually learned alot about how a carb works, which I didn't really understand before that. I cleaned the carbs and got all that green stuff out of the seat. then I turned them upside down and blew into the the float cavity and confirmed that a seal was possible. I put the carbs back on and still the leak was there. What was happening was the petcock is vaccuum operated off the negative pressure from the throat, and the seal that separated the fuel flow area from the vaccuum area had deteriorated. The fuel was bypassing the carbs completely and flooding the cylinders. I don't know how much gas made it down there, but, It was enough to back up a leak out of the air cleaner. I mean the oil was THIN.
You need to have the carbs properly cleaned. They should be SPOTLESS !!! Your float needles should stop the flow of fuel completely or you have a problem. Some carbs use an O'ring to seal the float needle seat to the carb body and these need to be replaced. The above statement does not relieve one of the need to always turn off the gas when parking the bike. The smallest speck of trash can cause the float needle to hang up and create all kinds of problems { like your house burning down }. If this is a race bike you should ditch the vacuum petcock. Ray
EXKid, listen to RB. Ditch the vacuum operated petcock if this is a race bike. I assume this is an EX by your user name. I modified the petcock on my EX. Remove the vacuum diaphram cover on the petcock and take out the rubber diaphram. On the inboard side of the diaphram is the piece that seals the flow when the engine isn't running. Gently clamp this piece in a vise and use a fine blade hack saw to remove just the part that sticks out from the diaphram leaving what will be the rubber diaphram itself. The diaphram will now look like a flat piece of rubber with the metal insert still in place. What you are doing is turning your vacuum petcock into a manual petcock. Put the petcock back together now simply using the diaphram as a gasket for the square cover. Plug the hole that the hose used to connect to, and cap the vacuum fitting at the carb. The major benefit of this modification is better acceleration and more power in the higher rpm range because the you are now not losing small amounts of vacuum to operate the petcock and the petcock itself now flows fuel much better. I picked up approximately 3 hp above 8000 rpm because the motor now wasn't starving for fuel. If you have modified your motor you will notice that it will pull better on the straights. If you have any ?s about the conversion e-mail me direct and I will try to explain better. BTW a Pingle won't fit between the tank and the frame. Dean
I would insure that all the fuel is out by running some fresh oil draining and replace it doesn't take much fuel to degrade oil. You can also buy new needle and seats which it sounds like it is time for, normally they are sold as a package (needle/seat) but most times it is the needle that has most of the wear.
What 591 says is correct. I've "gutted" my petcock and also no longer have reserve and have had no problems with my EX. More flow-the more better, especially if you are going to use CR carbs.
Yes I gutted the petcock when I found out that it was the source of my problems. I took out the little piston in there and cut a gasket to seperate the cavities. now there is no vacuum nothin. just a straight petcock that I turn off when I'm not running.
Arghh...where were you guys at last week when I asked about a Pingle for an EX500? I ordered one last week!
