1989 125 Force Spark ?

maxum247

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1989 125 Force Spark Problem!
Cylinders 1 and 3 have a constant but weak spark and the motor is misfiring on those cylinders.
Cylinders 2 and 4 have a constant strong spark at all times.
I changed out the stator with a new one when I first got the boat a few summers ago and that didn't help, still the same problem.
Have checked and cleaned all grounds several times over the seasons.
Checked and rechecked the wiring and all appears to be correct with no broken wires.
Swapped coils around and the problem didn't change.
I feel like I'm overlooking something but am not sure what else to try at this point.


max!
 

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jerryjerry05

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Re: 1989 125 Force Spark ?

Is the magnet under the flywheel loose or broken?
How about compression?
Check the connections on the keyswitch. J
 

maxum247

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Re: 1989 125 Force Spark ?

Is the magnet under the flywheel loose or broken?
How about compression?
Check the connections on the keyswitch. J

Forgot to mention that the engine picks up cylinders 1 and 3 and runs on all four from about half throttle on to full throttle topping the boat out at around 37mph.

Reglued the magnet a while back but there is a gap of 1/4" or less were the ends of the magnet meet, could that be causing the problem?
Is it possible that at low speed the gap in the magnet could cause the miss and weak fire on 1 and 3 then as the rpms come up as the throttle is advanced the gap in the magnet is passing fast enough that the gap no longer is a problem thus letting the missing cylinders gain spark and fire correctly?

Compression has been strong on all four cylinders each time I've checked it, in the high 140's or more on each cyclinder as best I can remember from the last check awhile back.

Haven't checked the switch. How do I test the switch to be sure it's working properly?






Thanks!

max!
 

maxum247

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Re: 1989 125 Force Spark ?

I've still had no luck getting cylinders 1 and 3 to fire correctly on my 1989 125h.p. Force outboard, still have a weak spark on those two cylinders.
Trying to get the boat out on the water for the 4th. Thanks!

max!
 

maxum247

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Re: 1989 125 Force Spark ?

I cleaned the connections on my 1989 125 Force outboard motor and also cleaned all the terminals and wiring under the center console as best I could, now cylinder no.3 seems to fire a little better but the spark is still weak where before the engine just misfired on no.3 producing a weak spark.
Cylinder no.1 hasn't changed at all, still misfires all the time and spark is weaker than no.3.
I ordered a new ignition switch today, I don't know if that will help or not but I should have it after work tommorrow. The switch that's on the boat is nearly 20 years old so I thought I would change it out for a new one.
I disconnected the rectifier and that didn't make any difference in the spark on 1 and 3 as best I can tell, but after hooking it back up the volt guage shows roughly 16 volts where before it read something like 14.5 volts or so I think, so I'm gaining a little here and there maybe.
I don't have the proper test equiptment to do some of the test that might help solve the problem I'm having and can't afford to throw parts at it so I'm sort of stuck guessing what to try next. I've checked everthing I can think of over and over again.
Any help solving the firing issue's I'm having with my motor will be greatly appreciated! Again thanks!

max!
 

tjello327

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Re: 1989 125 Force Spark ?

try to swap your cdi boxes around just to see if the problem follows the swap. If so, there's your problem. I dont think that is what it is but it might be. My engine did the same thing on the same cylinders, and when it was running it had a miss fire so I would tap on the cdi box and the miss fire would get better just for a very short time. I ended up buying a complete used ignition system off of e-bay and it solved my problem.
 

bustermin

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Re: 1989 125 Force Spark ?

you dont mention plugs or wires. have you changed plugs? they may be cracked or maybe a bad plug wire.
 

maxum247

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Re: 1989 125 Force Spark ?

try to swap your cdi boxes around just to see if the problem follows the swap. If so, there's your problem. I dont think that is what it is but it might be. My engine did the same thing on the same cylinders, and when it was running it had a miss fire so I would tap on the cdi box and the miss fire would get better just for a very short time. I ended up buying a complete used ignition system off of e-bay and it solved my problem.

I've checked about everything else but have not switched the cd modules around yet, waiting for new ignition switch to arrive today hoping that the it will take care of the spark problem, if not then I will try swapping the modules around. Thanks!

max!
 

maxum247

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Re: 1989 125 Force Spark ?

you dont mention plugs or wires. have you changed plugs? they may be cracked or maybe a bad plug wire.

I've put in brand new sparkplugs a couple of times even changing the brand of sparkplug and have swapped the coils around with the spark not following. I even changed a couple of the coils out with uesd ones recently that are known working with no change on cylinders 1 and 3. I've even run the motor at night looking for spark leaks in the plug wires, none found. Thanks!

max!
 

tonycrespo

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Re: 1989 125 Force Spark ?

I just went through a simular problem and it was the cd module...
 

maxum247

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Re: 1989 125 Force Spark ?

I just went through a simular problem and it was the cd module...

Thanks for the tip on the module.

I installed the new ignition switch I ordered today but it didn't help. So I removed all the wiring coming from the cd modules and swapped the modules around, rewired everything from scratch, same problem, weak fire on cylinders 1 and 3.

max!
 

tjello327

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Re: 1989 125 Force Spark ?

After all that you tried, there is one more swap I would try. Knowing that your ignition circuit for #2 & #4 are working properly, the stator is the last swap I would try. All you have to do is locate #2 or #4 stator lead that comesw from the stator and goes to the terminal strip and swap around with #1 or #3 (I would do one at a time) and see if the condition follows. I would bet it does. It almost has to. This is what I did and found that the no spark on my #1 followed when I swapped around.
 

maxum247

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Re: 1989 125 Force Spark ?

After all that you tried, there is one more swap I would try. Knowing that your ignition circuit for #2 & #4 are working properly, the stator is the last swap I would try. All you have to do is locate #2 or #4 stator lead that comesw from the stator and goes to the terminal strip and swap around with #1 or #3 (I would do one at a time) and see if the condition follows. I would bet it does. It almost has to. This is what I did and found that the no spark on my #1 followed when I swapped around.

After I rest up a bit I'll give it a try, I've been mowing the yard and working on the motor part of the morning.

max!
 

maxum247

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Re: 1989 125 Force Spark ?

I swapped the stator wires around as sugested (I beleive I did the test correctly) and there was no change.
I even tryed different ways of swapping the connections, I even swapped the coil wires at the same time no change. Still got a weak spark on 1 and 3 no matter what I did and strong spark on 2 and 4.
I think the only other thing I haven't tried is switching the trigger wires around, don't have a clue on what to do there.

max!
 

tjello327

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Re: 1989 125 Force Spark ?

Hmmmm, now you got me stumped. As for swapping the trigger wires around, I would think you do those just like the stator. You know what circuit is working and the ones that are not. Your trigger wires should be marked for which cylilnder they go to. Swap around #2 & #3 or whatever other combo between working and non working. It dont seem like the trigger would cause a weak spark but I am not too sure about that. I was told by my local marina that if you dont have the right test equiptment, then the best way to rule out things is by elimination by subsitution (swap.) Be sure you battery is fully charged. I doubt that will cause just two week cylinders, but it won't hurt. If all else fails, keep your eye on e-bay for a complete ignition system. I paid about $140 for mine and I changed everything. I kept blowing the same channel on one of my cdi boxes so I checked the stator and found #1 & #3 where not working right. I changed everything and have been boating ever since (have a few bugs to work out yet.)
 

maxum247

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Re: 1989 125 Force Spark ?

Hmmmm, now you got me stumped. As for swapping the trigger wires around, I would think you do those just like the stator. You know what circuit is working and the ones that are not. Your trigger wires should be marked for which cylilnder they go to. Swap around #2 & #3 or whatever other combo between working and non working. It dont seem like the trigger would cause a weak spark but I am not too sure about that. I was told by my local marina that if you dont have the right test equiptment, then the best way to rule out things is by elimination by subsitution (swap.) Be sure you battery is fully charged. I doubt that will cause just two week cylinders, but it won't hurt. If all else fails, keep your eye on e-bay for a complete ignition system. I paid about $140 for mine and I changed everything. I kept blowing the same channel on one of my cdi boxes so I checked the stator and found #1 & #3 where not working right. I changed everything and have been boating ever since (have a few bugs to work out yet.)

Thank's I'll try the triggere wire swap tommorrow.

New battery, battery cables are in good shape, new clamps at the battery, all grounds check out.



max!
 

maxum247

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Re: 1989 125 Force Spark ?

I think I may have found the problem!
I decided to get out my ohm meter and check the kill wires from the cd modules instead of just disconnecting them to see if the engine picked up cylinders 1 and 3.
I tried this test with the (new and old ignition switch) installed and found that with either switch in the on or off position that my analog meter needle would go about three quarters of the way across the scale, my understanding is that there should be no reading at all on the two white wires (kill wires) while disconnected from the circuit board. I beleive it states in my manual that the problem will likely be in the ignition switch or wiring harness if there is a reading. I've ruled out the switch as I have the new and old switch that I've tried with the same results, so I'm thinking it's going to be in the wiring from the console back to the motor.




A little later in the day!

UPDATE:

Ok now I'm really confused, after disconnecting the battery I decided to test the cd module kill wires again while they were still disconnected from the engine terminal thinking I would see no results but got the same results as when the battery was connected. What's with that, should it do that, is the wiring harness the problem, now I have my doubts about my findings.

max!

max!
 

chitownborn

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Re: 1989 125 Force Spark ?

max, try swapping the trigger wires around on your terminal board, on your no 1 cylinder take the org & grn and reverse them see if theres any change in the spark for that cylinder, if it works do the same for the other if not it was worth the shot it worked for me on my spark issue good luck don
 

maxum247

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Re: 1989 125 Force Spark ?

max, try swapping the trigger wires around on your terminal board, on your no 1 cylinder take the org & grn and reverse them see if theres any change in the spark for that cylinder, if it works do the same for the other if not it was worth the shot it worked for me on my spark issue good luck don

I'll give it a try tommorrow. Thanks!

max!
 

maxum247

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Re: 1989 125 Force Spark ?

I went to work on my motor today after taking a couple of days off from working on the weak spark on cylinders 1 and 3 issue and when I hit the key to start the motor I had no guage lights and the motor didn't make a sound. I did remove the ignition switch at one point but rewired it back according to a wiring diagram that came in a booklet with the boat when it was new, but it has run since then. I checked the circuit breaker and fuses and they looked ok. The trim/tilt and running lights still work fine. It had started everytime before today. Any ideas? Thanks!
 
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