[munro_capri]

Hi all, first post!
I have had an old evinrude 85hp v4 motor and was wondering what compression do you put in new rings/pistons... also is there an amount of time/hrs to do impellers and water pumps???? I have had the boat for a few years, no problems so far just replaced one throttle cable last year, do regular stuff, clean carbs and fog and change lower end oil yearly. Right now the compression is between 118 and 122 between all 4 cylinders. It starts fine runs good.
I do a lot of work on snowmobiles, rebuilds and maintenance and when the sleds get down to 120lbs time to rebuild.
Any other tips or info about this motor would be great.

[iwombat]

I'd say you have a looooong way to go before a rebuild is necessary.

With 120 in each hole, you might still be compressing the factory air.

[iwombat]

Oh, and welcome.

[munro_capri]

Thanks for the welcome!
Just leave well-enough alone for now or if it aint broke, don't fix it.
I have been reading the posts and am learning a lot from this forum, just like doo-talk, thanks to all those that share their knowledge!
Thanks iwombat.

[iwombat]

So, chiming in with my own experience and the piles of other posts I've read here.

The rule of thumb seems to be:
You're fine until it hits 100psi, then keep an eye on it. The idle will go first.

My '77 85hp reads 90psi in all the holes and runs like a champ at all RPMs.

[tashasdaddy]

the main thing is that they are with in 10% of each other. i like to do the impeller every 2 years, whether it needs it or not. they go out when they want to. i had a 71 135 merc, that i had put off the impeller, started on muffs in driveway, all good. got to the ramp 4 miles away, launched, started and no telltale. back on trailer, for an impeller. rather it went there than 7 miles down the river.