1985 RM 125 engine problem

adube59

Member
Jul 24, 2009
1
0
Hi i am new to the site i just got a 1985 RM125 for free it sat outside all last winter but ran the previous summer. Coolant had leaked into the crank case so i replaced all the top end gaskets. But i still can't get it running it is no longer leaking coolent i know it has spark it has compression but i can't tell if the fuel is getting into the cylinder. When i put my hand against the air intake side of the carb i can feel very little air being sucked in and a lot being pushed out i don't know if this is normal with 2-stroke engines or not this is my first experience with them. I took the cylinder back off thinking it might be the reed valves i cleaned them up and checked for cracks but it still won't start. I am almost positive the carb is not gummed up because i can see fuel coming out of jet openings on air intake side of the carb, also when i kick it over the bowl over flow port on the bottom of carb starts leaking out fuel. I am stumped by this one any advice would be greatly appreciated.

Thanks
Aaron
 

2stroke

Member
Nov 7, 2001
398
2


Is the plug wet? Thats an indicator of whether or not gas is making into the combustion chamber....

Try this...pull the spark plug, dump a shot glass amount of gas down the hole...quickly replace the plug and start kicking. If it fires and runs breifly then dies, then you do have a fuel delivery problem....= dirty carb... massive vacuum leak, etc.

If the carb is overflowing, the needle valve is probably dirty/gummy, and so the jets are probably also gummed up. And if its always overflowing, then the bowl level is too high and that will mess you up as well