1987 Force 85 HP

[hansencg]

My motor starts perfect, idles perfect and never kills.

However, it is sluggish to accelerate but eventually goes. There is a definite spot at about 3/4 speed where it jerks/misses/sputters. When I accelerate past that spot it loses power and when I decelerate past that spot it gains power. I can go past that spot and it goes pretty consistant at about 25 mph.

Twice yesterday I was able to "accidentally" get it to run perfectly. It jumped up to 30 mph and sounded and felt great. That was short lived.

I have replaced both "switch boxes" and the water pump. I ran SeaFoam through the gas tank and carb cleaner through the front.

Any ideas?

 

[MWBROWN]

Re: 1987 Force 85 HP

If you have not already replaced it, put in a new fuel pump kit. Pretty cheap fix.
Also, timing may be off, if fuel is not the problem. Others will help with the timimg adjustment, as I have not done that.
Check the throttle to see if it is opening the carbs all the way. They should be horizontal when wide open.

Good Luck,

Mike

 

[hansencg]

Re: 1987 Force 85 HP

Is there a way to test the fuel pump before installing a new one?

 

[MWBROWN]

Re: 1987 Force 85 HP

You can remove it and look it over. It should be soft and plyable.
If it is hard, it will probably be cracked, or have a hole in it.
It is it own gasket, so you want to be carefull removing it, in case it is in
good shape.

Mike

 

[hansencg]

Re: 1987 Force 85 HP

The gas line enters into the fuel filter. That has a single screw. That attaches to something with six screws and two hoses. Is that the fuel pump you speak of?

Chris

 

[MWBROWN]

Re: 1987 Force 85 HP

Yup, it is behind that. Clean the screen that is behind the single screw cover also. It is not too hard of a project.

Mike