gas in oil help!  By  bcgreatness (Read 12,391 times)

Here we go again, charging a buddy to fix something that we don't know how to fix!

1. I am wondering if this scoot has a canister to catch fumes and it is drawing gas through the vacuum line from the intake. When it draws vacuum it is on the downstroke so it would be sucking and if the canister is getting gas and not working it would draw gas through the vacuum line on the down stroke.

2. The Fuel Ratio screw could have fallen off or is missing or you forgot to put it back in. My crankcase got lots of gas in it because once the Fuel Ratio screw vibrated Loose and fell out. It would idle and run good and you can hear the difference in the tone of the muffler RUNNING RICH AS crap and a lot of the gas is going down into the crankcase.

Just a Thought
Alleyoop

update. upon inspection of the scoot today, none of the fuel has leaked into the motor overnight. 1 small victory. i checked the oil level and it was slightly higher then what i put in to it, slightly odd. ran the scoot for a few hours to let it warm up so i could check the oil again and see if it was where i filled it to. when i went to check the oil, it was still good looking, but i could smell the gas a little more then yesterday. not a super heavy smell like before but still a noticeable difference. for the hell of it, i borrowed my neighbors northern tools compression test kit and the motor was throwing out 80-90 psi almost good but a little too low for ignoring although it does run and i rode by a police speedometer showing a solid 41mph! .from my years of experience wrenching on cars and semi trucks, and all of my tests i performed, all the signs pointed to one thing. it was time to get down and dirty, oh joy... first order of business, check the piston rings. how does one do this? if you dont know, heres a tip. some people run compression tests with oil dry or oil full. you want to run an oil full test so you get accurate pressure. so first order of business, get a meat injector ( VERY handy tool for mechanics! ) fill it up about a quarter of the way with fresh oil, set aside. run compression test normally, note PSI. next, remove pressure gauge fitting from spark plug hole, then grab your injector. inject a very small amount of oil into spark plug hole a LITTLE! but enough to cover top of piston. tap the starter enough for the piston to make a full revolution. repeat the process 1 more time. next you hook the gauge back up and run your compression test again. if your rings are good, you will get a 5-15 psi gain on next test. that = good rings. so i know the rings are good. on to the next test today. next thing that comes to mind when having a some what low psi is the valve seats. time to pull the valve cover off. upon checking the valve adjustments, i noticed that the intake valve was set perfect but the exhaust was a little loose, but not enough to cause it to stick. while i was thinking about sticking valved it reminded me that if a valve does not seat properly then that would cause a lowered compression test and a possible fuel oil mixture but the adjustment was not that far off. the seats looked in excellent health upon outer inspection. so as i was saying about the signs pointing to one thing, i was certain of it now. it took only 30 mins to take the scooter apart enough to get to work on the head of the motor. after about 2 hours of removing parts and marking parts and jumping on computer to watch videos on here to double check i was not going to bomb this job, i finally got the head of the motor off and discovered that a very small piece of the head gasket had blown out from the piston side going to the exhaust port side. the side of gasket on piston side was blown out to about the side of a horizontal grain of rice, and the size of the gap on the exhaust side was about the side of a pin needle head. scraped off gasket, lightly sanded gasket seat area with 1000 grit sand paper. got a sheet if cork gasket maker and traced out the gasket shape, cut it out, and sealed it off with the red super high 700degree temp silicon gasket maker. it took me from 7am to 10pm today to finish putting it all back together. ive done a few head gasket jobs on cars and trucks, but i do have to say doing one on these small motors is a real PITA!!!!!! the most difficult part was juggling the valves, springs, and rocker arms while trying to align everything up! and i thought that the hard part was going to be getting it put back to proper TDC. its actually very simple assuming that you MARK ANYTHING AND EVERYTHING THAT MOVES WITH A REAL TIRE CRAYON! other then that it was all pretty simple once i took it apart to see how it all goes back together. so i finished the gasket job around 3 or 4 pm, and while i let the head gasket dry up, i started work on the CVT, taking the cover off, cleaning it out, checking the bearings. once that was finished and put back together, i took a short dinner break. i went out, lit a smoke, walked over to the scoot and kicked it once, no start, twice? nope, 3rd times a charm! nahh, 4th kick, fired right up! i let it idle while i finished my smoke and then took it for a ride. i tell you what that thing was pretty quick for a 50cc before but its almost as if it took a good 12 hour nap and woke up with the energy of a 5yr old. it runs about the same speed but gets there slightly faster. i dont even have to do a compression test to know it will be right but i will do one tomorrow for the hell of it after i change the oil a few more times, flush gear oil and refill that and maybe a new spark plug. now i know yall are wondering where the pics are, well sorry, im not sure if i posted it when it happened but i threw my phone at a wall. it still works but the screen is broke. too bad that would have made this a good post... well im beat, this little 50cc has put my body and mind through a 1000 mile marathon. happy scooting all