150cc won't run

[mira88]

Have a Chinese 150cc that just stopped running. Installed all new ignition has good spark. New carb, good comression timing right on. Will start hard and run fast only with lots of gas out the exhaust. Vacuum all check fine. HELP

[chris-bob]

How many miles?  Are you the first owner?  Any modifications?  Have you adjusted the carb recently?

[mira88]

2010 scooter about 400 miles just stopped running at stop light. Installed new carb and runs same. Lots of raw gas out exhaust pipe. Will only run very fast and very hard to start. Has been running fine up til this time. Ignition timing checks fine. Good blue spark at spark plug, new spark plug. Motor runs same with new carb as with old.  No real adjustment on this carb. Vacuum appears to be good with no leaks. Has 95# compression. Thanks for reply.

[goosestale]

Start with the valves, here's a link to the valve adjustment guide.

http://www.scooterforumonline.com/index.php/topic,1720.0.html

[mira88]

Just check valve clearance and right on.005. Timing chain looks good and very clean inside with only 400 miles. Everything appears to line up right timing mark and cam shaft. Can't figure it out. Running fine then all of a sudden died and appears to be getting too much gas. New carb installed and acts same as original carb. All vacuum lines checked and good.

[chris-bob]

Double check your intake.  Sounds like a leak to me if the carb and valve clearances are fine.

[mira88]

Found a bad diaphragm in the vacuum fuel pump. New fuel pump stopped the flooding but motor still hard to start. Taking it to a shop in the morning. Thanks for all the replys and web site on adjusting valves.