Force 50 dies when throttle advanced when engine hot

Malahini

Recruit
Joined
May 11, 2011
Messages
2
Symptoms on early 90's Force 50:
Engine cold; engine starts, usually first crank, and runs to full throttle OK.
After running at mid-hi power for 30 minutes or so, I shutoff engine.
Wait 5 to 10 minutes and engine is 'hard to start'. Finally after a few attempts engine starts to idle 800 rpm and seems OK. When throttle is advanced, RPM rises to ~ 1200 rpm and then engine immediately and abruptly dies. Scenario happens repeatedly. Occasionally I get engine to go past 1200 rpm and it runs fine until shutoff then restart is attempted.

Have replaced most ignition system components and Carb has been rebuilt by 'professional'.

Is this a fuel pump problem?
 

gramkaran

Cadet
Joined
Sep 12, 2004
Messages
8
Re: Froce 50 dies when throttle advanced when engine hot

Re: Froce 50 dies when throttle advanced when engine hot

Malahini, I would check the fuel pump diaphragm for hair-line cracks... what happens if you pump the fuel bulb before starting?
 

Fullscreen

Recruit
Joined
Apr 14, 2010
Messages
3
Re: Froce 50 dies when throttle advanced when engine hot

Re: Froce 50 dies when throttle advanced when engine hot

I would replace the fuel pump altogether as they are usually pretty cheap.
That problem sounds like a fuel problem so I think you can focus your attention there starting at the tank.
Look for air leaks, change old hoses and check the float as well as the needle and seat especially the o rings and crush rings if there are any in there. I know you said the carb was just done but you are going to be your own best troubleshooter here. Post your findings. Its funny how writing the stuff down helps you keep track and focus on what you are doing next. Good luck, you can get it done.
 

exp2000

Petty Officer 2nd Class
Joined
Dec 10, 2009
Messages
148
Re: Froce 50 dies when throttle advanced when engine hot

Re: Froce 50 dies when throttle advanced when engine hot

Man, I have exact same problem with my 90hp force. And I cannot figure out what is going on. Carbs rebuilt, pump rebuilt, fuel lines replaced, rechecked and re-rechecked. Idle screws checked to 1 turn out. I am pissed.
 

emoney

Commander
Joined
Jul 19, 2010
Messages
2,551
Re: Froce 50 dies when throttle advanced when engine hot

Re: Froce 50 dies when throttle advanced when engine hot

Definitely look at the diaphram at the very least. Are you using a fuel/water separator?
 

Malahini

Recruit
Joined
May 11, 2011
Messages
2
Re: Force 50 dies when throttle advanced when engine hot

Status of problem on Force 50 dies.....
Purchased fuel pump gasket/diagphram rebuild kit and installed it last weekend. Hope to make test run at lake this holiday weekend. I will post outcome.
thanks for the input.
 

shadow7g

Cadet
Joined
May 9, 2011
Messages
23
Re: Force 50 dies when throttle advanced when engine hot

Man this seems to be quite an issue with these engines. Mine is doing the same exact thing! Ill let u know what i come up with
 
Top