Compression test

[BobbyL]

Hello all...I have a 12 year old Briggs and Stratton Intek 20 hp model 406777-0139E1. Did a compression check and got 120 on one cylinder and 150 on the other. Both numbers seem acceptable but I'm thinking they should be almost the same. Any thoughts on this? Thanks for any input. -Bob

 

[ILENGINE]

The standard is normally no more than a 10 percent difference. Those are not bad number though.

 

[BobbyL]

Thanks for the info. Was wondering if the compression release function during starting was causing the difference. I'm in the process of installing a new carb due to rough running and having to run on almost full choke. Figured I'd check compression first. Thanks again. -Bob