1987 Force Problem

[Atomictmex]

I have a 1987 85HP Force Motor which ran great when I first owned it. Late last summer I started having problems with loss of power as if one cylinder was not firing, lots of smoke, loss of power. Thinking this was a carb problem, I cleaned all three carbs. After cleaning carbs I decarbed engine by running seafoam through motor as instructed on thread on this forum. Engine would run fine for short spurts then seem to start to run rough running rich with middle plug fouling. Over time the motor seem to run worse until it would barly run after starting. Talking to several people with similar problems I replaced the coil for cylinder 2 and had similar results. Compression checks out fine but fuel runs out of lower unit when motor is started and it would hardly run when started. After replacing both voltage regulators the engine starts and runs great until it runs for awhile then starts same problems as previous. I did adjust screws on each carb to 1 and one quarter turn out during process, I am running out of ideas help needed.

 

[Frank Acampora]

Re: 1987 Force Problem

You should not have raw fuel running out the engine leg. This can come from the carb itself, or from a rich running cylinder. Similarly, you should not be fouling only one plug.

This leads me to suspect that you still have a problem with carb #2.

1. Is the float sticking in the down position or incorrectly positioned too high causing a flooding condition? With the carb turned upside-down the float should rest parallel to the casting under the pressure of its own weight.
2. Is the inlet needle sticking in the open position or is the rubber seat (or rubber needle tip if so equipped) damaged so it does not seal?
3. Did you replace BOTH fiber washers (one inside the bowl and one outside) on the brass bowl nut? Failure to replace the inside one will cause the carb to run rich at all speeds.
4. Is the casting dip tube damaged or cracked, usually by overtightening the brass bowl nut, to bypass fuel around the high speed metering jet?
5. Did you damage, enlarge the hole, or remove the high speed fuel regulating jet in the casting near the bottom of the fuel bowl?
6. Did you damage or enlarge the metered holes in the casting above the butterfly? (under the welsh plug on top of the casting)
7. Is the idle mixture screw or seat damaged to the point where you can not lean out the engine to stall?

 

[Atomictmex]

Re: 1987 Force Problem

Thanks for the advice, the valve seats are pressed in on these carbs so no replacing them (very simple carborators). Could be one of the other problems you mentioned. May have to replace entire carb to solve this one.