continuous fire on cylinder 1

[fisheymikey]

hi everyone,

i have a 1989 force 125, with the plugs out grounded i could clearly see all cylinders firing but the cylinder #1 firing continuously.

i have swapped in and out 5 different cdi moduals and almost all react differently. i.e 2 cylinder not firing or 1 weak spark etc...

here is what i done to try and diagnose the problem. trigger 48ohms on all cylinders, 768 on the stator, flywheel checked nothing broken changed all connections, i use timing light independently on each wire and seams to fire at the right time, i also tried the spark tester and its jumping 1/2 inch. and #1 is firing hotter

can the trigger even if the ohms are within spec can it produce differen spark at diffent times?

i know it difficult to diagnose from a distance i even tryed bringing to a mechanic told him all my procedure i have taken thanks to you guys and told me his exact word " you are better equipped then me" holy pooper scooper that was depressing..

i just want to thak all you gentlemen that has helped me with this ordeal but im at my last try. unless i get another full ignition system im thinking this force gonna get a scrapyard solution.

i believe in the term KISS= keep it simple stupid but i feel more like im stupid then simple.

 

[gm280]

Oh fishymikey don't give up. There is always a reason for such things. I know you feel like you've done everything, but obviously not or it would be running. So time to regroup and post what you have tried thus far so we can offer suggestions. Your ignition setup is a trigger with a CDI pack and I know there are CDI pack instructions available to explain how to test it out. Others probably know exactly where those instructions are located and will chime in with that info. JMHO!

 

[fisheymikey]

so today im going to do some more swapping of components. today changing the trigger. then redo the timing and linc and sync.

but i did find something odd...

i left the key switch on and found my baterry very low! keep in mind all my electronics except my bilge pump is connected to a switch board therefore there is no other electronics pulling my battery. the plug is out and my bilge pump is not working.

when i turn my key to off i could gradually see my voltage go up slowly and when i turn it off it goes up slowly... i would say 0.01 volts per second up when off and 0.01 sec down when on. hope that make sense. im guessing the only component drawing power when key switch is on is the starter selenoid.. could that draw sooo much power? the battery is a marine starter batter with 1000 craking amps.

 

[Snakeforce]

I typed up a nice detailed response, but this damn site burped and it all disappeared. So, I’m typing this one in Word and will cut and paste it when done. Something to keep in mind if others have run into this problem.

First, I have no experience with your particular engine or EI. But I’ve spent a bit of time with EI’s engines, and troubleshooting. So here’s my two cents worth.

Okay, first, your battery drain with the ignition key ON is probably the EI. The module needs power and will draw down your battery over time. It is not the starter solenoid because it is out of the circuit until you turn the key to START or press the START BUTTON, whichever you have.

I want to restate your problem in an attempt to clarify. You say that all the plugs show spark and appear to be firing at the correct time, which is near TDC. Yet the #1 plug fires continuously. By fires continuously, I interpret this to mean it fires every time another cylinder fires. You can check this by spinning the engine and watching #1 and another plug. Put them side by side if you can. Do it for all the plugs and #1. If it turns out that this is the case, then I suspect your module is bad. It cannot be a short between the wires firing the coils or they would all fire in unison.

You said you tried 5 different modules. I assume they are all used. My guess is they all have problems and each one is different. Used electronics are always a crap shoot. Even NOS electronics are still old electronics. Old solid state stuff has a shelf life, even if it is never energized. The other point is you said that when you changed one module for another, the problem moved to another plug. That tells me, the problem resides in the module.

Before you relegate this engine to anchor status, if you know the history of the engine (not run on Kmart oil) and it is otherwise a good running engine, I would suggest that you convert to aftermarket electronics. I have gone down the route of used electronics (tested and warranted by a local marina) and although they did solve my problems, I don’t expect them to last forever. And they are prices like gold. I too considered retiring my 150, which I bought new, but when I looked at the price of a new Yam 4 stroke 150 or 175, which is $14K, I realized I could put a ton of new electronics in this engine and still be way ahead of the game.

I'’ve stopped buying used OEM electronics. I just put a new CDI Electronics stator in mine when it quit charging. If the EI goes bad again, it will get a CDI Electronics replacement, even if it means I need to replace my new stator with the version that eliminates the converter box. Still cheaper in the long run.

If you buy a used motor to replace this one, unless you know the motor, you are just buying somebody else’s problems. If you know this motor, it is probably better to keep it going than to start over with other used motor of unknown history.

By the way, the Sheriff’s boat on the Hudson had a pair of Force motors on it, I think they were either 125 or 150 and the have thousands of hours on them (based on input from the shop that maintains them) and were still going strong a few years ago.

Lastly, as you work thru this, only change one thing at a time. If you change multiple items, especially if you are using used parts, you will never know if you solved one problem and corrected another. Good luck.

Regards,
Rob

 

[Jiggz]

For cylinder #1 to continuously fire, I can only see two reasons it would do such a thing. First, it could be the trigger wire (orange and green) are shorted to another set of trigger wires, and as such #1 plug (and the other plug it is shorted to) will look like they are continuously firing. The other reason would be a faulty CDM, but in this case the same symptoms on #1 should also be indicated on #2 since both are fed from the same CDM.

Instead of switching CDM's that you are not sure are working properly, try switching instead with a known working CDM, i.e. CDM feeding #3 and #4. Now if the problem follows, i.e. the continuous firing moves over to either #3 or #4 then you know the problem is with the CDM. However, if the problem stays with #1 then the problem is NOT with the CDM.

The next move is to trace the trigger wires from #1 (OR & GN) from the terminal board all the way back to the trigger unit to make sure it is not shorting out to any of the other sets of trigger wires. If there is no indication of shorts (read resistance between the orange wire and all of the other trigger wire sets and it should read open or infinite) and also to ground and it should read open.

Conduct a test again and if possible post a youtube link so we can see how the motor runs.

 

[fisheymikey]

Well thanks guys l.!!

That was a very good read due to the fact i dont know if i have a good cdi i went ahead and baught2 cdis from standard magneto.

I also bought a trigger from a 120 1990.. does that trigger will work in my 125? 1988 or did i waste my 75$ i had no choice store was closing and its about 1 hour away.

Im getting my 2 cdi sometime early september

Let me know what u think?

 

[Jiggz]

Based from your original post, there is an indication the other CDM is working properly on #3 and #4. As previously mentioned, since this is a known working CDM then you should switch it around with that one on #1 and #2. Could it be a bad trigger? One best way to find out is to read resistance between each set of wires and also from each set of wires to the other set of wires. Between each wire there should be set resistance while resistance between each set of wires it should read open. In short, each set of two wires are the leads of each coil in the trigger. There are 4 units of trigger coils (with 4 cylinders) in the trigger each with a set of wires (2 wire leads). But each coil should not read resistance with the other coils meaning they should not short to each other.

 

[fisheymikey]

in regards of my original post ill clearup some issues. i stated that i was having a continuos fire on #1 but also i had many different situation like#3 not firing or #2&4 not firing due to always changing or swapping my cdi boxes.

that is why i ordered 2 new CDI boxes from standard magneto.

but i have a different question i hope someone know how it works. i have read on a diffrent post that the flywhel center magnets could be the problem,

i had to remove one of the "fins" of the center magnet due to the fact it was rubbing and creating a lot of heat. can my flywheel be the problem? does the flywhell tell the trigger when to fire?

thanks for the info

 

[fisheymikey]

No Title

 

[Jiggz]

I'm not really sure which fin you are referring to with the inside magnet of the flywheel. But if the inside magnet is rubbing against the trigger, it is either the flywheel was installed "cocked" or the trigger was off center. Anyways, from the pic you provided it seems the inside magnet looks normal.

As for the question what tells the ignition system to fire, it is actually the inside magnets in the flywheel timed to each cylinder generates a small voltage in the trigger coil sends it to the CDM for the CDM to discharge its capacitor and feed it to the ignition coil and to the spark plug to produce a spark.

If you have a DVA you can check the voltage output of each set of trigger wires (4 sets since you have 4 cylinders) and you should get a +0.5 Vpeak from each set. If you do get these voltages from each trigger set of wires, then the flywheel and trigger should be working accordingly. If not, then you need to check resistance between each set of wires and you should get 48~52 ohms on each set. If you get all resistance correctly, then maybe the flywheel inside magnet is not working accordingly.

 

[fisheymikey]

thanks Jiggz!

the Fin im talking about is the thin metal plates staked up on top of each other.the magnets seem to be held by them. what are they used for deflection of current or heat?

when you stated the term "Cocked" where you saying if the magnets were exceeding those metal thin plates?

 

[Jiggz]

By saying "cocked" I mean the flywheel was installed not aligned properly with the shaft. Although there is a key in the shaft, it is more for aligning the flywheel with the #1 piston rather than being parallel with the shaft. And yes, the flywheel can be installed "cocked" or skewed to the shaft and hence will rub against the trigger unit.

 

[fisheymikey]

wow... i would never guess the flywheel could go on crooked... with the way its tapered and with sooo much pressure on the flywheel.

but good to know ill check if by some chance i have installed it right.

​cant wait to get my new cdi's hope that will be my final issue

 

[Jiggz]

It may be a long shot on why a tapered flywheel can be installed crooked to the shaft but that is no different why such a flywheel will rub against the trigger unit. Obviously it is not the fins on the magnet housing that is causing this nor is it the trigger unit rather something was not installed accordingly why there is rubbing. I doubt the magnet housing fins got old and worn out (or grew up) and decided rubbing against the trigger unit or the trigger unit for some reasons grew due to old age and started rubbing against the housing magnet.

If you think by cutting off some of the magnet housing fins (actually you are probably referring to the steel laminations) has detrimental effect on the trigger unit, then I recommend you get a new flywheel and also a new trigger unit and trigger advance plate. And if problem persists, then you know the problem is neither the trigger unit, advance plate or the flywheel. But if with new units and the new flywheel is still rubbing with the new trigger unit or advance plate then it could be the shaft is too worn out allowing the flywheel to go down lower than it should be.

 

[fisheymikey]

Jiggz i really appreciate all the input you provide..

I found something that i cant explain...

maybe its my trouble from the beginning.

between each yellow and blue sets i get 768 768

when i have one lead to ground check every wire from stator i get 2 of the open, the other 2 yellow or blue reads 12 mega ohms

why should there be any resistance? it should be reading open right?

 

[fisheymikey]

i did some further testing...

with no cdi connected i was able to get some readings with my homemade dva adaptor..

stator both sets 184v 184v

on trigger im getting 0.42 to 0.38v

looked at a video at a guy testing the stator and said sometimes when a engine get too hot the windings could ground within. my engine did get hot once and maybe thats what triggering my short. the question is even if it produces 184v on both could that restance create any problems??