1983 Yamaha G1 New Everything Wont Run

Bobdabiker

New Member
I have a 1983 Yamaha G1 2 stroke. I'm totally stumped. New parts so far.
New carb
New plug
New fuel pump
New coil pack
New fuel filter
New gas
Compression at 122
Will not start. Took off exhaust. It turns over sputters. Notice oil gas coming out exhaust hole. Carb is adjusted correctly. Will not fire up even when Spraying ether in carb. If I choke or open throttle if floods it I can smell the gas. Please help I'm at my wits end.
 

Bobdabiker

New Member
There is some oil on the passenger side when it's turning over. But its holding 120 lb compression. Notice some oil coming out exhaust when it tries to fire.
 

Rstaley

Cartaholic
When the crankshaft seals leak on those old 2-stroke engines, it doesn’t have anything to do with what comes out of the seal. It is all about what goes in. In a 2-stroke engine the entire fuel mixture goes through the crankcase to get to the combustion chamber. That is how the innards get lubricated, because of the oil in the gas. When the crankcase seals start to leak, they suck in air during the stroke that supplies the fuel to the combustion chamber and “lean” out the mixture to where the air vs the gas (with the oil in it) is way out of proportion (was too lean). The ratio of to air to fuel should be about 14.7 to 1, and it gets WAY too much air. Good luck, Ron.
 

Rstaley

Cartaholic
P.S .I’d try squirting some starter fluid in around the ends of the crankshaft while trying to start the engine to see if it tries to start while doing it. If it does, the seals need to be replaced.
 
Top