1994 Force 40 hp outboard acceleration problem. Please help!

SilverRsx

Cadet
Joined
May 20, 2011
Messages
6
The boat has been in storage for the past 2 years. When I tried to prep it for this season a few weeks ago, it wouldn't start. Took it to the shop and the technician cleaned the carburetor and fixed the primer. Everything appears to be in great working order.

I had since taken it to the lake twice now and have the following problems. My motor started fine, but doesn't want to idle sometimes and the motor tends to cut out after a few minutes when the throttle is at 60% or more. It would run great, but would suddenly and quietly cut out (sounds like it just ran out of gas). After it died in this manner, it would take a few tries to start back up. When I maintained a slower throttle speed, it was fine. Prior to this, I actually had never had any problems with this boat!

Any advice is very much appreciated!
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
17,923
Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

Sounds like the vent is clogged or the hose is collapsing.The Ethanol were putting in the gas can mess with older hoses.Replace ALL hoses,squeezie too.
Put an inline filter between the carb and the pump.Rebuild the pump.J
 

SilverRsx

Cadet
Joined
May 20, 2011
Messages
6
Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

Thank you for your advice. I checked my vent and replaced the hoses and primer bulb. Found some green sludge at the hose connector too so I will be replacing that as well. Anyways, waiting for some parts to come in so I can rebuild the fuel pump and change a few other things as well. We'll see!
 

SilverRsx

Cadet
Joined
May 20, 2011
Messages
6
Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

Ok, the parts came so here is a list of what I did so far. Unfortunately, these didn't fix my problem. Engine still idle poorly just like it did before. The old diaphram seemed a little scretched, but it wasn't too bad looking.

-replaced the diaphram in the fuel pump (wanted to replace the valve as well, but the repair kit didn't come with any)
-replaced both spark plugs
-replaced inline fuel filter

Now, that we know it isn't the diaphram, does this sound like a bad valve in the fuel pump or something clogged the carb?
 
Last edited:

Endevor

Cadet
Joined
Jun 6, 2011
Messages
8
Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

I have an 85' 50 hp force with similar problems. I have gone through the carb, rebuilt the fuel pump, changed the plugs and water pump (just needed changed not relevant to the problem). Just before mid throttle there is still no change in power. last to check is the float level and fuel pressure. Those valves in the fuel pump didn't come in the kit and are hard to inspect.
 

Endevor

Cadet
Joined
Jun 6, 2011
Messages
8
Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

I found my issue. After checking the fuel system again I checked the electrical side. Fouled points was the culprit. Cleaned them up now running like a champ.
 

SilverRsx

Cadet
Joined
May 20, 2011
Messages
6
Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

ok, so I opened the carb and found a bunch of particle that was clogging it up. It appears that the particle were small pieces of gasket that had broken off due to wear and tear.

Anyway, the WOT is fixed on the engine after replacing the gasket and cleaning the carb. She runs like a champ at WOT. Unfortunately, engine still has a tendency to die sometime at idle and she does produce more smoke than normal. IF I shift to forward gear slowly, sometimes, engine will cut out too. Engine does start back up fairly easy though so I have been avoiding the problem by shifting to forward gear and accelerating quickly.

What do you guys think? Is this a mixture screw problem? Does this sounds like the engine is running too rich?
 

jerryjerry05

Supreme Mariner
Joined
May 7, 2008
Messages
17,923
Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

Re: 1994 Force 40 hp outboard acceleration problem. Never had this before!

Sounds like the idle is too low. 750-800 in gear and warm.
Air screw:gently in to bottom and out 1 turn.In water and warm in gear,turn in till it coughs/buck/stutters etc.Then out 1/2 turn.
install a small filter between the carb and the pump,it will stop a lot of junk in the carb.J
 
Top