Proper Compression for a 200 Ocean Runner

[mikey456]

I am considering buying a 200HP Johnson Ocean Runner. Its a 1991. I am told the Compression in all cylinders COLD is 100PSI. Does this sound acceptable or should it be higher and I am potentially buying a worn out motor. Also, does $2K sound like a lot for this Motor? Any other suggestions when looking at this year and HP is greatly appreciated. Tks!

 

[Jayrock]

Re: Proper Compression for a 200 Ocean Runner

A compression test should be done when the engine has warmed up. If those numbers are the same when it is warm, varified by you being there during the test, all is good. I rebuilt a 1992 200 and after break-in my compression numbers were not that high. These big V-6 2 strokes do not typically have compression over 100 psi as far as my experience goes. If the seller will let you, check the lower unit oil. If the oils comes out like a milkshake, or has lots of big metal particles on the plug be cautious. If the motor runs well and looks good, 2k is the absolute limit of what I would say is acceptable. Since the engine is 20 years old Offer 1600 and try to meet in the middle.My .02

 

[nymack66]

Re: Proper Compression for a 200 Ocean Runner

Here if FL you can pay a certified mechanic to verify the engine for issues beyond the fresh paint, and the stories the seller tells you.
I recommended this upfront money its worth its weight in gold..
Compression is grossly overrated in a purchasing decision, for example if I simply spend some money to have the heads milled bingo high compression ..you get the idea ...I agree unless this motor is well taken care of and have a replaced power-head with low hours ...

 

[mikey456]

Re: Proper Compression for a 200 Ocean Runner

Thank you for the input!!