1988 evinrude 225 compression

joshcom

Recruit
Joined
May 8, 2011
Messages
5
Boat - 25' Aquasport walkaround cuddy
Motor- 1988 evinrude 225 v6

I was Having a problem with low power and poor idling, after it had sat for nearly 2 months end of last season, pulled it out and winterized it.

Drained the fuel, changed fuel filter, all new plugs, added fuel stabilizer to new gas.
Started it up and running nice (out of water), and sprayed out carbs with carb cleaner.

I then tested compression, 60,60,62, 60, 62, 62.

Are these considered low comps? I was under the impression that I didn't want to below 90 and within 5 across the board.

Should i just put it in and run it and see what happens or should I swap out the head gaskets and take a look at the cylinders, pistons and rings?

Thanks,
Josh C - RI
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: 1988 evinrude 225 compression

You may have had a slow cranking engine or a faulty gauge. The good part is that all of the readings were fairly close. I'd run it one time, pay atentioin to the running quality, power, speed, rpm, etc. THen check the compression again with a different gauge.

Compression of that model is normally about 95 psi on the starboard bank and 90 psi on the port bank.
 

dehydrated

Petty Officer 1st Class
Joined
Dec 25, 2009
Messages
299
Re: 1988 evinrude 225 compression

when you sprayed the carbs did you take all the jets out and spray the passages put new kits in them
 

j_k_bisson

Lieutenant Junior Grade
Joined
Oct 6, 2010
Messages
1,082
Re: 1988 evinrude 225 compression

Hey, my just reringed motor is only in the low 80's. I know it is the guage, bought it from harbour frieght. It's the spread, not the number. You could "drop" the guage and get higher numbers. Is your guage certified?
 

joshcom

Recruit
Joined
May 8, 2011
Messages
5
Re: 1988 evinrude 225 compression

Have yet to do the carb kits, although its on the list. My fear was that by rebuilding carbs without being certain about the issue, it could be waste of time and/or money.

I'm going to take the guage to a local shop and have them test it, or I'll just hook up to my compressor and see what I get.

Thanks for the great ideas and input.

JC - RI
 

Ancloter

Seaman Apprentice
Joined
May 3, 2011
Messages
36
Re: 1988 evinrude 225 compression

Was it pressure tested cold? That'll produce low readings. The numbers are pretty even so that's a good sign. It's running nice though so why 'fix' it? If you want peace of mind on engine compression:

Warm up engine. Disconnect wires and plugs. Unhook fuel line or disconnect fuel injector elec. connectors. Move throttle/idle control to WOT. Crank 4x and read pressure.
 
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