1990 Force 50

[brian470]

I have a 1990 Force 50 that starts and idles fine. However when I give it throttle it begins to accelate but then bogs down, even though it is turning high RPMs and the motor is racing. I just had a tech check it out, he replaced the water pump and said everything else was fine, yet after this service continued to have same problem. I'm thinking it is a fuel delivery problem but am unfortunately quite ignorant about this. Any suggestions?

 

[eurolarva]

Re: 1990 Force 50

Racing tends to be a lean condition. If this is the case the motor should be repaired before it starts wearing down the pistons. You could have an air leak somewhere that is causing this. Does your primer bulb stay firm when you pump it up. When motor is running does it stay firm. The first thing you should do is get a manual for this motor. Second is buy a carb rebuild kit and rebuild the carb. It could be a number of things but carb rebuild and fuel pump rebuild are the cheapest and easiest things to do.

 

[seekcasey]

Re: 1990 Force 50

I purchased a boat this spring with a 1990 Force 50 that exhibited the exact same symptom (and I thought it was a fuel delivery problem also). The local marina checked it out - first they said it was the coils or CD causing the problem, but it turned out it was a bad propeller! Put a new one on and the motor has been running GREAT since! Even picked up 5 mph on the top end speed. Check it out - maybe it's your problem too. Good luck.

 

[jasper astro]

Re: 1990 Force 50

Seekcasey...I have the same motor also. Have you experienced any electrical problems like power pack, stator or anything like that?<br />I have spent alot of money due to a battery change. ....jas....

 

[seekcasey]

Re: 1990 Force 50

Jas...I have not had any other problems with my motor since replacing the propeller. Starts up first time and idles good too. I added a Sting Ray hydrofoil stabilizer two weekends ago and it works great. The boat nows planes out almost immediately upon accelleration.

 

[jasper astro]

Re: 1990 Force 50

What kind of propeller did you purchase?<br />I was looking for a four blade with a different pitch than what i have on now. I believe this is a factory propeller i have now. Has the pin exposed near the cone. A friend of mine has a Johnson 1990 50 hp and the propeller is 4 blade, and the pin is covered by the housing. <br />My propeller seems to be fine though, believe it or not it outrun the johnson....and eventually towed it in this saturday at the lake....overheated...buzzer....and they were laughing at my Force earlier that day....ha....

 

[12Footer]

Re: 1990 Force 50

You stated "it bogs down even tho it is turning high RPM's".<br />This sounds like a classic case of spun-out hub in the prop.<br />Take some high visability nail polish or Testors model paint, and paint a line from one blade of your prop,all the way to the prop nut. <br />Let dry.<br />Take it for a spin.<br />If the line breaks, and is no longer aligned, the hub is spinning. Remove the prop, and have it rehubbed at a prop shop.