1989 Force 125 Bored .30 over NOT RUNNING RIGHT!

[pnwboat]

Re: 1989 Force 125 Bored .30 over NOT RUNNING RIGHT!

I experienced similar issues like you after re-building a 1988 125HP motor. Turns out that I had a several wires on the trigger that only had a single strand of wire making connection with the spade lug connector on the end of the wire. On my motor, there was a small piece of black heat shrink tubing that covered the spot where the wire is crimped and soldered to the spade lug connector. You cannot visually tell that there were broken strands because the heat shrink tubing covered that spot. The trigger OHMed out per factory specs. I replaced all of the spade lug connectors, crimped and soldered new ones on and it solved my problems. I also added an additional ground wire from the coil/CD Module plate to the engine block.

Sounds like in your case you may also have a couple of bad CD Modules since the problem moves around with them, but first check those wires that I mentioned above.

 

[92rslt1]

Re: 1989 Force 125 Bored .30 over NOT RUNNING RIGHT!

Mark,

I really am sorry to hear about your difficulties with that engine.

I am not an expert on outboards though I am rebuilding an earlier version of that motor right now.

That being said I used to run a garage and was an expert in engine tuning.

After reading your thread I have a few comments I would like to make that may help you get to the bottom of the situation.

First of all when a spark plug is fired the more fuel/air mixture and the higher the compression the higher the resistance to the spark or in other words more energy that is required to make the spark and the higher the load on the coils and triggers.
Also the faster the motor runs the higher the compression and fule/air mixture which also increases the resistance to the spark.

Now another thing to consider is that engines can be picky about which spark plug you are running. Sometimes when rebuilding an engine it s nessesary to raise or lower the "temp" or resistance of the spark plug. For instance with Bosch spark plugs you will have a series that runs from HR7P to HR9P with the 7 being the coldest and the 9 being the hottest. We often had to run colder than spec plugs on Chrysler engines for them to run well. Champion plugs which I believe are the recommended plugs for Chrysler/Force outboards is one of the coldest running plugs on the market.
You may want to look at running a different plug or the stock one i fyou are not.

Finally when the resistance increases on an ignition circuit all kinds of things can happen. For instance connections that are weak or have poor contact will fail or wires that have excess resistance will find a new route to disperse the energy like via a short or I have even seen it go right through shielding, carbon can provide just enough conductivity for electricity to cross a barrier.
You see it sometimes inside distributer caps when spark has been arcing under load as fine black lines around the cap.
I have been shocked a few times by the spark jumping right under/through the cap and even the spark plug boots.

I believe you mentioned that you found wires that had melted shielding, those wires should be replaced. Once wires are over heated they almost never perform as they should.

Also if any wire looks old, dirty, oily, cracked or somewhat rigid replace them. These tasks only take a little time and a little money and can often solve problems like you are experiancing.

I once came across a 1952 Metro that hadn't run in a decade. The owner had spent over a grand on mechanics trying to repair it with not luck. It took less than an hour and turned out to be the trigger wire going from the points to the coil. it was broken inside of the boot. Looked perfect and passed an ohm test but failed under load.

Good luck!

J

The thing I see that you didn't mention is when changing heat ranges.. nothing in the plugs electrode is different. The heat range of a plug is merely a measurement of how fast the plug disperses the heat created by combustion. A hotter plug IS NOT a hotter spark... same spark, different heat retention properties. The only way to get "hotter" spark is by adding a larger coil. So by running a hotter plug then normal, theres more risk of pre detonation occurring due to the plug not cooling fast enough.

 

[Unforcefull Force]

Re: 1989 Force 125 Bored .30 over NOT RUNNING RIGHT!

Everybody who uses these forums are great people! Another reason why I love boating so much; boaters usually stick together. You can drive on any given roadway in the United States, break down, and have 100 cars drive by with no one stopping to make sure everything is okay. Break down on the US waters and you can't get people to stop trying to help! Me personally, I?ll stop to help anyone anywhere any time, no matter what the situation. Thank you all for the continued responses!

I spoke to CDI electronics today. He seems to think that it is the CDI Packs as well. He said there is about a 7 day turn-around. I will send them in today. I really hope that is the problem.

I tried switching out the trigger to the old one again just to make sure. (I am starting to get really quick at removing the flywheel/stator). Same thing again, I re-installed the brand new trigger. Now, the waiting game.

-Mark