Compression PSI for a 94 Superjet

[chumbiwumba]

I am looking into buying a 94 Superjet. The owner says it runs but I wanted to run a compression test. Does anyone know what the original spec was new and what is the lowest acceptable pressure and difference between cylinders.? I'm not even sure what the stock engine is for this year a 650 or 701?

The owner told me also that he has used it only in saltwater. Aside from obvious external corrosion anything else I should be wary of. To be quite honest I am put off by the fact that it was used mainly in the ocean but I'm trying to keep an open mind because if it is serviced properly after the ride that can make a difference. His asking price is reasonable.

[K6jet]

Re: Compression PSI for a 94 Superjet

Most two cylinders should read 134 to be decent, but some go as high as 157 like mine. If its under 120 then give it a test ride to make sure it runs good. Im not sure of what it should be for that engine though, so take that in mind

For variance in compression, I'd say more then 14 psi is nearing unreasonable.