1996 Force 90 HP Idle/Low RPM Question

[FISHVA88]

Hey guys,

I have a 90 HP Force on my bass boat that I purchased about a year ago. I probably had it out about a dozen times last season, and I took it out today for the first time this year.

Just a little background: The motor fires up everytime pretty easily (first few cranks), and runs great at/near WOT. I have no idea what kind of RPM's I'm getting at WOT, and I've never had a compression test done. However, it's been a very reliable motor for a first time boat owner on a budget. Has never left me stranded or anything like that.

The only issue I've had (ever since first time I took the boat out) is the motor wanting to cut off at low speeds, specifically causing a problem when loading the boat back on the trailer. When I'm approaching the trailer and easing off of the throttle, the motor will cut off while still barely in gear. It's never caused any major problems, but it puts me in a potentially bad situation if the boat isn't perfectly lined up with the trailer on final approach, as you can imagine. I basically have to assume I will not have control for the last 10-20 feet of my approach. If I keep the throttle at a level that allows the motor to keep running, I risk running the bow through the bed of my truck lol.

I have a Seloc manual for the motor, and I've heard Force motors are fairly easy to work on, so I could probably figure out something basic if I'm pointed in the right direction. Is there anything specific that I should look for? Is this a timing issue?

Sorry in advance for my lack of knowledge/terminology. I'm pretty green when it comes to mechanical issues.

Thanks!

 

[foodfisher]

Re: 1996 Force 90 HP Idle/Low RPM Question

Hi, sounds like your idle rpm's are too low (tach). Without knowing what the rpm's are (tach), most if not all engine problems will be very hard to diagnose. I suggest you invest in a tachometer as an important tool to make your motorboating experience more pleasurable. (tach). Compression test is said to be also as important. Clean plugs help.

 

[jerryjerry05]

Re: 1996 Force 90 HP Idle/Low RPM Question

Profile? Location? You might be close to someone who can help???
boats . net Remove the spaces. They have parts diagrams for your motor.
Look it up and start getting familiar with the parts and pieces of your motor.
Find the towershaft. That's how you adjust your idle.
On the carbs,there is a screw with a spring. Towards the rear of the carb.
Turn it in till just seated(gently)then out 1 full turn.
That's the initial setting for air/fuel slow speed mix.
Then in the water,motor warm,slowly turn in the top carbs screw until the motor cough,.bucks,stalls.
Then out 1/2 turn. Do the same on the other.
Like food says get a tach it will only benifit you.

 

[FISHVA88]

Re: 1996 Force 90 HP Idle/Low RPM Question

Thanks for the replies! I'm located near Harrisonburg, VA.

Jerry, I appreciate you taking the time to lay out those steps for me. I'll check out that website and see what I can figure out from there. You said to make final adjustments to those carb screw while on the water. I guess it wouldn't work with the motor running on muffs on land due to the backpressure difference between running on muffs vs. actually running in the water? Just checking.