I just got a used YS 140L and it seems like it is low on compression I can turn the prop over and over with little resistance im not sure how much compression they should have does any one know what the compression should be at


Thanks Tim

One way is to start the engine and let it run for a minute, then shut it down, let it cool then flip the prop over, if it is still low then most likly a new ring is called for, or the liner is scored and the ring can't seal.
Or if it won't run then it has other issues.

Will YS Service Aus

OK I will give that a try thanks


Thanks Tim

Well I fired the YS 140 up it did start right up and ran great I ran 20/20 fuel through it with a 17-8 APC and it was turning 8800 rpms ran a tank and a half through it and it ran great

I got this motor and a world models fun 3D with 6 futaba 3151 servos new in box and a reciver and battery all new in box for 175.00 the guy thought the motor was tost and so did I but once I got fuel in it and ran it had lots of compression


thanks Tim

Pleased to help

Will YS Service Aus