Looking at buying a different boat and need to know how to/what to look for on a compression check.I have the compression gauge already,just need to know what to do to check the motor.

Help!!

just screw in the gauge and crank over the engine until the gauge stops going up. I have always heard the psi. should not vary more that 10% from highest cylinder to lowest cylinder but from my experience in the past a good engine wont even vary that much. You need to know what the proper compression should be for your engine. Make sure the throttle is wide open and all of the spark plugs are out.

Thanks for the input gambler,I need to find out what the proper compression is for an Evinrude 200....

I've searched the internet a little but cant find anything but where to order manuals.Got any ideas?

ya, try www.marineengine.com it is a great site for mechanical questions. It will most definatley have more than you want to know about your engine.When you get there click on message boards or discussion links?? and then click on outboard engines then scroll for your answer. hope this helps

fivebasslimit, I went on marineengine.com and looked up your engine.since I did not know the year I guessed at 1998, I figured that may be a starting point for you. A 1998 evinrude 200 should have 100psi. to be in the acceptable range. Most article I found said they were closer to the 110 range.They also said on some of the rudes the starter will kick out when checking compresion with the plugs out so if this happens you will need to put the plugs back in,this wont be as accurate but will still tell you if all of the cyl's are in range.