1989 Force 85 hp

[rrt2b2010]

I bought this motor a few weeks ago 1989 85hp Force. it came on a 1989 Maxum... 20min on the lake and it started to lose power, so I shut it off and it never started again.. before our journey at the dock, it took a few minutes to start and when I put it in gear it kept dying, eventually it went in gear and didnt stall. the motor ran fine for about 20 minutes. took it to a mechanic close by and the compression tested cylinder #1 100psi, cylinder #2 46 psi and cylinder #3 22psi.. I am still taking the boat to my friend who is a certified mercury mechanic for a second opinion.. but any ideas?

 

[foodfisher]

Re: 1989 Force 85 hp

Check the psi's yourself. Sympathies extended if they are correct.

 

[rrt2b2010]

Re: 1989 Force 85 hp




i have heard that these motors are really easy to work on.. what is an estimate of cost to fix this compression... worst case scenerio... my friend is a certified mercery mechanic and works cheap for me...

 

[jerryjerry05]

Re: 1989 Force 85 hp

Low compression on 2 cylinders next to each other usually means a bad head gasket.
Easy fix.
Just changing the head gasket,I charge about $100.That includes,diagnotics and a $40 gasket,
To rebuild with 1 bad cylinder about $850-1100 and shipping$
That includes a complete strip and reseal along with carb rebuilds,linc and sinc.
1-3 new pistons and bearings.New gaskets etc
Just making sure you mixed the gas/oil 50-1
After the fix,change the IMPELLER!!!

 

[rrt2b2010]

Re: 1989 Force 85 hp

Man. That would be awesome if it is just a head gasket.. I did mix the oil 50:1. I used a mixing bottle and put the ounces required for the amount of gas I pumped. So having good compression on 1 cylinder. And bad on two cylinder beside each other could mean that the gasket between them is bad?

 

[foodfisher]

Re: 1989 Force 85 hp

That's pretty much what he said.

 

[jerryjerry05]

Re: 1989 Force 85 hp

Pull the head and check???

 

[rrt2b2010]

Re: 1989 Force 85 hp

We are gonna pull the head and chck tomorrow.. I will know exactly what the issue is tomorrow.