Compression on older 150hp evinrude

[bksah2]

Hi All Anyone know what the compression should be on a older 1986 150hp evinrude ..I know on most outboards the comp. should be over 100 psi and even on all cycls.. But I am getting conflicting info on theses motors ..Some posts on google state that the big old motors were only rated at 80-90psi and some other post state 110-120..they state some as loopers and some as crossflows I think,,, which I have no idea what either are..THANKS

[Destroyer]

If it's any help, my 1991 200 HP Johnson's compression is in the low 90's.. right where it should be.

[THEFERMANATOR]

86 150 EVINRUDE will be a cross-flow engine and have a bubble back exhaust on it most likely. The looper engines will have a one piece block whereas the cross-flow engines will have plates that bolt onto the sides of the cylinders and the exhaust will also have a plate bolted on it between the 2 heads. The main thing to look for is that all the cylinders are the same or within 5-10% of each other. Normal compression on that engine should be in the 90-100 pound range on a fresh tight engine, but years of use and carbon build-up can and most likely will change those numbers.

[tsubaki]

Had an "84 150 horse on the V before repowering with the current motor.
At the time of swapping out the engines it had 89/90psi on all cylinders, same as it was 3 years prior to mounting it on the boat.
Like ferm said, most important thing would be near even compression between all the cylinders.