1989 force 85 loading up and fowling plus at idle trolling

[nhogan171]

I have a 89 force 85 and do a lot of slower trolling at idle for walleye, I just installed this motor and noticed the other day that after trolling for a couple hours that I had fowled a plug when leaving to go in. I pulled all three plugs and they all looked like it was running rich. should I adjust the mixture screw to try and solve this problem or is this just common problem for this motor?

Thanks in advance!

 

[pnwboat]

Re: 1989 force 85 loading up and fowling plus at idle trolling

Most older 2-stoke outboards in that horsepower range manufactured in that time frame do not like to run at trolling speeds for extended periods. If you try to lean out the mixture, then you risk burning a piston when you run at higher RPM's.

You can minimize this problem by making sure your fuel recirculation system is in good working order.

 

[jerryjerry05]

Re: 1989 force 85 loading up and fowling plus at idle trolling

Like PNW says check the fuel recirc system.
If only fouling one plug?? What one?
The middle runs the fuel pump and possible the diaphram has a hole?
Set the air screws at 1 turn out and leave it them there.
I fished Saginaw Bay for 5 years trolling for Eyes and never had a problem.
Compression test?Spark test?

 

[nhogan171]

Re: 1989 force 85 loading up and fowling plus at idle trolling

Good Compression and good spark, I'll have to check the fuel pump. I just bought this motor and I believe it sat for some time. I will also try setting all three mixture screws at one turn out.

 

[foodfisher]

Re: 1989 force 85 loading up and fowling plus at idle trolling

85 hp engines weren't built to troll! You'll have to add an additive (sea foam), to help prevent fouling, or carry an extra set of plugs to change out, or clean the plugs as needed.

 

[jerryjerry05]

Re: 1989 force 85 loading up and fowling plus at idle trolling

My opinion. If your gonna add anything to your gas add a fuel stabilizer(for winter) an E stabilizer for water(regular operation)
Seafoam doesn't do anything for carbon build up. It might?? help with water/condensation?
Mercs Powertune or OMC's Engine Tuner is the best carbon remover.It can be used in your gas,small amounts.

 

[tater76]

Re: 1989 force 85 loading up and fowling plus at idle trolling

When you troll with a 2 stroke motor for extended periods of time, it is wise to stop every 30-45 mins and rev it up for a few seconds to clear it out, then proceed on. I have done this with my 89 85hp for the last three seasons of Kokanee fishing, and never have fouled plugs.