85hp force motor

[Jimbo82]

I have a 1989 bayliner capri.With a 85hp force motor.The previous owner said it will do 45mph.I only got it to 20 tops.Motor seems to be stressing.I cleaned out the filter and so on and can't find the problem.This is my 1st boat.Bought it for 700.

 

[UtahBoating]

I had a similar issue recently on a new purchase of my 85 hp. For me the problem was 2 fold. First I had the engine trimmed wrong and was running the lock pin in the wrong position so I was plowing water - basically I was forcing the bow down into the water and trying to push it the way I had the motor trimmed. I also found that I was getting some slippage in my prop. The rubber bushing was shredded a bit and causing the hub to slip. When I trimmed the motor properly and put a new prop on I gained 9-11mph. I still don't think I am where I should be but I can go 32mph now which is a HUGE improvement.

Other factors to check are make sure you are getting spark, I used one of the those inline spark testers. Also a compression test to make sure all 3 cylinders are close to each other in compression are good places to start.

 

[UtahBoating]

No Title

In the photo if you look closely you can see the rubber is torn up near the center of the hub causing some slippage.

 

[foodfisher]

45 sounds a bit embellished. Mid 30's more realistic for normal use (nonracer).

 

[SkiDad]

most Bayliner hulls are not fast - they are easy to plane and ride nice family boats, but not fast. My boat tops out around 37 mph with my current prop - will get about 40 with a higher pitch prop but useful for serious skiing. Most 85 hp bayliners were good for about 35 mph. that being said i would think you should at least be in the low 30's - i would check for a spun prop hub if you hear the rpm climbing on you. If prop is good look at Franks video at top of the Force forum.