Mercury 850 What to do? Help!

[outdoorsman37]

Hello, I just was given a Wellcraft 165 Airslot which has a Mercury 850 on it. The lower unit is off and taken apart. Some of the parts are rusted. The powerhead looks clean. I tried to compression test it by hooking up a battery and turinging it over. It tested at 95-100 for all four cylinders. I sprayed some WD40 in the cyclinders and then the compression was around 110 in all cylinders. So, what should I do? Should I keep it and try to fix it up or buy a lower unit or replace the rusted parts or dump the whole engine or sell some of the parts? The controls are all hooked up. They seem to be working fine. The engine turns over fine.

Any help would be greatly appreciated. Did I do the compression right. Could it be higher if I missed a step?

Thanks!

 

[64osby]

Re: Mercury 850 What to do? Help!

I think 110 is OK for a free motor, 120 prefered, as long as they are all equal your doing pretty good.

Rusted parts - clean them up and see how bad they really are. If they are pitted at a seal or bearing location you have some issues.

Buy a new impeller / water pump housing kit and you should be good to go.

I've never used it but Seafoam seems to be the thing for bringing an old motor out of storage. Somewhere on this site there is a "sticky" on how to bring an old motor out of storage and do it the right way.

If your close to SW Mi I'll take it off your hands and you won't have to worry about it