aftermarket ignition

[woodnknots]

I have a 1991 Force 90 hp. It runs pretty good, but when it idles for a while (like sitting waiting my turn to come in at the dock, or idling past the "no wake" zones) it will sometimes die.
My father recommended I get an aftermarket ignition upgrade that would give it a hotter spark, thereby hopefully burning more fuel, more efficiently, and preventing the "quits" at low idle.
Has anyone done this, and what are the possible ramifications of doing so. Also, does this kit even exist for the Force?

 

[roscoe]

Re: aftermarket ignition

I don't know what ignition upgrade you could possibly put on there.

With proper maintenance, that motor should be able to idle without dying.

Properly mixed fuel, fresh fuel, using synthetic oil, and using the correct sparkplug, all will help.

Cleaning and rebuilding the carburetors, along with a proper link and sync, is probably all you need.

Three different ignition systems were used on the 90hp, in 1991.
You need the correctly matched sparkplug for the ignition you have.

System 1 - 1991E models, used blue coils and cd modules, and Champion UL-18V plugs.

System 2 - 1991H thru 1992C models, used Black coils and a switchbox with exposed terminals, Champion QL-76V plugs.

System 3 - used black coils and an enclosed switchbox with bullet connectors, L-76V plugs.

The fuel recirculation system should also be cleaned out, and a thorough decarb process should be done.

All time consuming, but pretty easy and cheap to do, and is supposed to be done every few years. Previous owners probably never did any of it.

 

[woodnknots]

Re: aftermarket ignition

I agree... A thorough decarb is probably LONG overdue. I got this boat late last year, and the previous owner had someone take care of the motor periodically, but I have a feeling he never did good decarbs, if ever.

After de-winterizing the boat about 5 trips to the water ago, I didn't have any problems with stalling at idle until yesterday, while sitting and waiting for my turn at the dock (dock was VERY busy). I remember a minor decarb I did last year (just ran a full can of seafoam through a tank), and it seemed to help a lot.

I'll try the decarb.
Thanks Roscoe!!

p.s. Thanks for the spark plug info. I don't think I have the correct plugs. I'll check.

 

[woodnknots]

Re: aftermarket ignition

I made a mistake in the year... It's a 1990 Force 90. Does that one still take the champion UL-18V plugs?

 

[roscoe]

Re: aftermarket ignition

yes - blue coils and cd modules = Champion UL-18V plugs.

 

[steelespike]

Re: aftermarket ignition

I don't have the specs on your motor but you may want to be sure the carbs are synced, need to open the same amount at the same time.Also carefully adjust the idle mixture screws should be adjusted as close to the same as possible.Adjust warm in gear.Idle speed around 700 rpm.If you do a lot of no wake operation you may want to consider a conventional plugs just be sure of the heat range and reach.