1983 FORCE 85 HP, honey do list.

Jack Daniels

Petty Officer 1st Class
Joined
Sep 21, 2007
Messages
266
Ok so you all know by now that i have low compression, approximately 85 on all three cylinders. So i am writing this to present my to do list during the winter in hopes of getting this bad boy to run as long as possible.

1) Decarb the engine using appropriate methods-- I heard that this can increase compression.-- should i wait until spring to do this?

2) carb cleaning-- not sure hwo to do this but will do some research prior to messing with it. Carbs scare me a little, is there a way to give them a good cleaning without removing them from the motor?

3)rebuild the water pump/impellor-- should be easy enough with a repair manual.

4)New spark plugs after DECARB

5)Rebuild the fuel pump, is this necessary? Not sure how old it is or if its even been redone, i heard its really easy to do. Also should i install an inline filter and or a kit that will allow water to drain prior to going to the engine?


Low compression question-- do you guys think its ok to remove the head to determine if they cylinder walls are in bad shape or to check the pistons out. If the cylender walls are not scored to bad is it possible just to replace the pistons and rings without taking the whole thing apart? If the rings were going or bad would that be the cuase of my low compression? How hard would it be to replace the pistons and rings?

I am assuming that the low compression is due to the age of the motor and not the condition of the boat. I have all the maintenance records of the boat and have looked over them. There was a soft spot in the rear of the boat but that was professionally replaced last year. The mechanic said it was very localized rot and was limited to the plywood deck. He said the transom and beams looked to be in good shape. Someone said the low MPH could be due to water logged foam, how do i look into this?

Sorry for such a long post but you guys are very helpful and with yoru help i think i can do all this work myself if necessary.

Thanks again

Jack
 

bgbass.1

Chief Petty Officer
Joined
Aug 1, 2007
Messages
558
Re: 1983 FORCE 85 HP, honey do list.

Do decarb in spring you have to warm it up first then spray into carb. shut it down remove plugs spray into cyl. and turnover by hand a couple times then let sit 2 hours. carb. has to be removed to clean its not hard when you take apart lay parts out in order removed take out high speed jet and clean manual will help. if no problem with fuel pump leave alone.as far as pistons and rings you have to tear motor down. but you can take head off to check cyl. walls and pistons for damage as well as head gasket. you must replace head gasket once removed. if gasket no good that could be your low compression.
 

roadrunnr

Petty Officer 3rd Class
Joined
Sep 15, 2007
Messages
99
Re: 1983 FORCE 85 HP, honey do list.

If you've read other posts on this forum from Frank, I would recommend taking his advice and installing an inexpensive fuel filter that you can get from any auto parts store for about $3.00. Install this filter after the fuel pump and before the carbs. This is cheap insurance from debris clogging a fuel needle, resulting in a lean condition which will trash a cylinder in short order. Frank states that the fuel pump check valves can disintergrate and cause this problem.
 
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