1990 Force 90 idle problem/ Motor dies in gear

[beemerjunkie]

I have a 1990 Force 90 motor on my bayliner capri. Once i get the motor started when i put it in gear it shuts off. I have already emptied the tank and put new gas in. I would appreciate any help.

Joe

 

[badly bent or broke]

Re: 1990 Force 90 idle problem/ Motor dies in gear

Should be idling at 700-800 rpm according to the manual. I had the same problem and through searching this forum I found that I first needed to check for obvious things such as fuel line restrictions, dirty fuel filter, etc. I ended up rebuilding the fuel pump which wasn't too difficult or expensive. That cured my idle problem. If you've got a fuel filter between the fuel pump and the carb, observe it to see if it is staying full or nearly full of fuel. Before I rebuilt the fuel pump, my filter was partially or mostly empty when running. After the rebuild it now stays full when running. I did have to advance the idle speed up closer to 800 rpm to keep it from dying when I put it in gear.

 

[beemerjunkie]

Re: 1990 Force 90 idle problem/ Motor dies in gear

Thanks for the reply. My local Mechanic is going to look at it again tomorrow. This time he is going to look at it on the lake. He did look at the fuel pump and said it was ok. my fuel filter never gets full so i will ask him to look at that again.

JR

 

[GrindKore]

Re: 1990 Force 90 idle problem/ Motor dies in gear

I own the exact same motor 1990 FORCE 90. First of all when you shift in gear, make sure you do it quick. The idle dead-zone on the throttle is large due to the shifter cams that operate gears. If you take your time moving through it, the engine will bog down due to prop being engaged. Unless you quickly add power to overcome this RPM loss the engine won't have enough momentum to turn over and will die. First time I got my FORCE 90 on the water, I was not used to it and thought something was wrong with it.

Also, you can adjust the idle screw, just be careful not to over-rev the idle otherwise you will start grinding the gears in the lower unit when shifting.

 

[college_guy]

Re: 1990 Force 90 idle problem/ Motor dies in gear

mine does that too, but the question is when i slow down after speeding, and i put the forward back into neutral it bogs and dies.. does that happen to you too or do you know what could be the cause of this

 

[NMShooter]

Re: 1990 Force 90 idle problem/ Motor dies in gear

Does your fuel prime bulb ever look like the engine is pulling a vacuum? Make sure that your tank and fuel line couplings are working correctly. I was having this same problem due to lack of fuel at low rpms. For some reason at higher speeds it was able to draw enough fuel through the line to stay running.

 

[college_guy]

Re: 1990 Force 90 idle problem/ Motor dies in gear

I dont know what a vacuum is. Is it where it seems like there is no extra air in the bulb, and at the same time the bulb is not fully out. yes, sometimes it seems like that. i also took off the fuel line leading to the fuel pump. it seems to be pumping a good amount of gas as well. i hope it is the pin in the carb. float. it seems to get stuck when the pin is shoved up by the float. could that be the problem? i should get the new kit by tomorrow. ill letcha know if thats the cause

 

[crump]

Re: 1990 Force 90 idle problem/ Motor dies in gear

The bulb for your fuel line should always be a bulb. Never sucked in so to speak. If it is, that is the vacuum they are talking about. This would mean that your fuel tank is not venting. I also received some good advice about using the process of elimination for problems. Try not to get fixed on just one thing or one system. I would also do a compression check to make sure all is good with pistons and powerhead. I have a 85 hp Force and it would run at idle but the second I went to put it in gear it would die. Went through fuel system and carbs and all was fine. Finally discovered that #2 piston pressure was at 30psi (not good). Problem was blown head gasket between #1 and #2 piston. Hope this gives you some help.

 

[jerryjerry05]

Re: 1990 Force 90 idle problem/ Motor dies in gear

Like someone said do a comp/spark test.Then in the water check RPM.750 -800 in gear.
Usually the vent if clogged will stop you from running at higher speeds.
Check the vent lines and then change the soft hoses going to the motor.Get a new squeezie.The bulb has a1 way valve in it.if the ball goes flat then it could be bad.I like Mercury products for this.Tempo I have found can be bad from the box.Then the pickup in the tank could be blocked.
Ethanol is messing up a lot of motors.It's delaminating the inside of older hoses causing clogs in the carbs and fuel filter.Check for soft hoses and junk in the fuel filter.Check the fuel pump diaphram.Should be flat and no holes.J