85 HP force motor

[GT2efiero]

I've been struggling with this boat for a while and spent countless dollars taking places to get it fixed. This my last resort before i sell it. I will put the ear muffs on it and it runs fine but when i put it in the water the engine will idle but as soon as i try to accerlerate it dies and i have to paddle back to shore. I was wondering if anybody had a step by step guide on what will work. It will go into all gears and stay running but as soon as we try to move it kills right away. I am extremly greatful for any help you can provide. Thanks,
Dan

 

[roscoe]

Re: 85 HP force motor

Hi Dan, sorry for you troubles.
But welcome to iboats.

Engine needs 3 basic things to run.
Compression in the cylinders, fuel delivered to the cylinders, and spark from the ignition.

And an outboard mechanic needs a repair manual. The Clymer manual is pretty good for Force engines.

Check for compression, hoping for 120#+ on each cylinder.

Check for spark, a good strong blue spark, that will jump a 7/16" gap.

If you have good compression and spark, then you have a fuel delivery problem.
A dirty or misadjusted carburetor will cause poor fuel delivery, and it will die when you try to accelerate.

Can you tell us what you have had done to the motor so far?

What year is the motor?

 

[RRitt]

Re: 85 HP force motor

this probably won't help you but my first guess would be plugged up fuel filter. My second guess would be fuel pump diaphram. My third guess would be a pressure leak between engine block and fuel pump diaphram. My fourth guess would be low compression on the cylinder that drives fuel pump. My fifth guess would be something other than fuel delivery. It just seems unlikely that all three carbs would give out at the same time.

if it was a compression or spark problem then it probably wouldn't start very easily or idle smooth. That's why all my guesses focus on fuel delivery having a glass ceiling.

 

[GT2efiero]

Re: 85 HP force motor

I believe it's a 92. I've had the ignition box replaced. I believe that the compression is good across the board. I'll check the spark, and i don't think the carbs have been clean or adjusted since we bought it in 95 i believe. It worked well for 4 years then started to act up. Last time i took it out, it would idle in gear and the only way that i could get going was to gun it right away. The engine was screaming but the boat was only going about 10 or 15mph. the front would raise up and the back sink but it really wouldn't go any place. I know that a while back it was really tough to start and i think there was something with the blub and fuel filter/line but i'm not sure if those have been replaced.

If i remember anything else i'll post it.
Thanks,
Dan

 

[johnson1989]

Re: 85 HP force motor

Sounds Like you have a Dropped Cylinder from either Bad Compression or Not Getting Spark. Do Like Rosco Said and check all the basics, I bet you will find the culprit there. Test Spark By Joe Reeves Directions or just pull your kill and check spark off the plug out grounded to the block. You can also pull plug wires while it is running to see if you see a change to find the faulty cylinder.

Also Check for pinched wires, broken wires. They can cause issues, check at night and try running with the cover off. It doesnt seem like you are getting full power.

Lastly you will need to get your Carbs rebuilt sometime. Manuals will help. Check those, report back and someone will be able to help

 

[johnson1989]

Re: 85 HP force motor

Disregard pulling your kill switch, Haha I dont know why I said that. Your not going to get spark if you pull the kill switch. If pull the plug and look for sparknig to the block it can give you an idea but best to use reeves way. Just be careful of igniting Gas

 

[GT2efiero]

Re: 85 HP force motor

Yeah i'll give those a shot this weekend, I'm finishing up my first year of college so things are hecktic.

I'll write back once i figure things out, or don't figure things out.