1986 85 HP Force - 2 problems

[mveley1]

Hi all, Noob here. I just bought an 86 Bayliner with an 85 horse motor in very clean condition.

My first problem is that the engine has no power. I could only get up to 25 MPH with 2 people on board. The boat does not have an RPM guage, but it does not rev very high. I have not done a compression test yet, but will within the next day or so. When I got home I looked at the plugs which the previous owner had just replaced. Two of them looked good, but the third actually looked brand new. It wasn't dirty at all. That was all that I had time to do so far. Does this mean that this plug was not firing or maybe not getting any fuel?

My 2nd problem is the trim does not hold. The motor raises and lowers nicely, but when I accelerate (if you can call it that) the motor drops all the way down and will not raise until I am nearly stopped.

Thanks for any help that can be offered.

Mark

 

[jerryjerry05]

Re: 1986 85 HP Force - 2 problems

When you do a comp test do a spark test too!!!. The trim if it leaks all the way down will probably need the pump replaced.Not the electric motor just the hdy pump.
There is a thread earlier this week about a place to buy that pump motor. Jerry

 

[roscoe]

Re: 1986 85 HP Force - 2 problems

Need to check compression.

Sounds like low compression, or no spark on one plug.

Don't run the engine in its current condition.

 

[mveley1]

Good comp - no spark @ #1

Good comp - no spark @ #1

OK, my friend finally remembered to bring his compression tester along, and all 3 cylinders are at or near 125. The first plug is not firing. After swapping around the wires etc. I think that I need a new CDI switch box. I tried the "spare" wire from the 2nd box, but did not get a spark. Does something else need to be wired to the other side to create the spark? The cheapest CDI box I can find is $217. What is inside of this mysteroius magical box that makes it cost so much? Am I missing anything? Does anyone know where to find parts like this that do not cost an arm.

I will deal with the tilt/trim later, I just want to get running first.

 

[jerryjerry05]

Re: 1986 85 HP Force - 2 problems

Sometimes on E-bay.Most places are expensive.
Make sure all your connections are tight.Sometimes a loose wire will cause your problem.Jerry