1989 85HP Force, CDI problems

[devl]

This motor has 3 cylinders and 2 CDI boxes. The front box controls cyl 1 and 2 and the rear box controls cyl 3. Originally it was only firing cyl 2 and 3 so I swapped boxes and cyl 3 wouldnt fire so I replaced the rear CDI box (note at this point the boxes were switched so the front became the rear). Now the original CDI box that wasnt bad is only firing cyl 1 but not cyl 2. Before we swap boxes again I was wondering if there is some other issue I should look at that would cause the box to go bad or did we just run into some bad luck? Really need some help on this as Striper season is getting shorter and shorter by the day.

 

[CharlieB]

Re: 1989 85HP Force, CDI problems

The ignition system has a three triggers, one per cyl, a poor connection or a dead trigger will not trigger the box.

A DVA Meter is used to test the cranking output voltage of each trigger, somewhere in the range 1 1/2 to 3 VAC

Remember that there is NO RETURN on electrical parts, test TWICE, buy once.

 

[john from md]

Re: 1989 85HP Force, CDI problems

Get a Clymer manual and a Multimeter. Check the resistances in the trigger and the CDI modules. Clean all of your connections and grounds. Many times, no spark issues stem from poor connections.

John

 

[devl]

Re: 1989 85HP Force, CDI problems

We swapped boxes again and cyl 2 still doesnt fire. So is this most likely the trigger or stator? What is the proper way to test the trigger and stator and can it be done with just a multimeter or is a DVA really necessary? All the wiring and connections look good but I fried my multimeter trying to read current from the coil (probably a rookie move). Im going to get a new multimeter but would really appreciate the proper testing procedures to make sure I do it right and track down the faulty component.

 

[john from md]

Re: 1989 85HP Force, CDI problems

Forget the DVA if you fried a multimeter. Just get a meter and follow the troubleshooting section of the Clymer manual. CDI modules go bad more than any other part in the system. You can ohm out your stator and trigger coils and know for sure if they are good or bad. The process of elimination will take you to the CDI modules without using a DVA adapter.

John

 

[devl]

Re: 1989 85HP Force, CDI problems

John I appreciate your reply but its all foreign to me....Im a car guy so I know the basics but these outboards are crazy...can you let me know a step by step guide? I know the stator and trigger wires but how do you perform the tests needed to make sure they are good....and what equipment besides an expensive DVA do you need?

 

[shytownborn]

Re: 1989 85HP Force, CDI problems

your trigger has three pairs off wires, each trigger has two wires org/grn is no 1 red/wht no2 and another org/grn for no3. disconnect org from no1,red from 2 and org from3 from your terminal board. take your meter set it on ohms and connect one of the leads to one of the disconnected wires and the other to its mate you should read between 45 to 50 ohms on a good trigger pair, if no readings on any set your trigger is probably history. your stator wires should be blue yellow, youll have two sets of them, one bl/yell will feed the front mod and the other will do the rear mod, take your meter and ohm the matching sets, on a good stator you should read between 500 to 700 ohms good luck don oh ya all you need for these tests is just a regular vom meter

 

[john from md]

Re: 1989 85HP Force, CDI problems

All you need is a Digital voltmeter from Radio Shack or Harbor Freight and a Clymer Force Outboard Shop Manual. The manual has all the information on resistance, volt and amperage readings for the entire electrical system.

If you know Ohms Law and can work on cars, you can work on these engines. They are much easier than working on today's automobiles.

John

 

[devl]

Re: 1989 85HP Force, CDI problems

Thanks Don, I tested the trigger and stator wires and all of them were within spec. Retested the coils by swapping...those are all good. Unhooked the kill wire still no change. Even tested the spark plugs on the off chance but all good. So I guess we are back to the CDI box. Is there a procedure I can test the boxes with only a multimeter? John, we're going to order the Clymer manual for future use but would really appreciate a quick CDI test procedure so we can get parts ordered if needed.

 

[devl]

Re: 1989 85HP Force, CDI problems

Also John I checked every connection and they are all clean and tight, wires look good as well.

 

[john from md]

Re: 1989 85HP Force, CDI problems

There is no way to test the output of the CDI modules without a DVA adapter for the multimeter.

One test you can do is to see if one CDI module is shorting out the stop circuit of the other. Disconnect the boat harness White (early stop circuit) or Black/Yellow (later stop circuit) wires from the terminal board and separate the blue CDI stop wires. Crank the engine and see if you get spark. If you do, the good cdi has a bad circuit that is causing it to short out the others stop circuit.

When you are spinning the engine for troubleshooting, make sure you ground your high tension leads or plug shells. If you don't feedback will ruin the CDI modules.

John

 

[devl]

Re: 1989 85HP Force, CDI problems

One test you can do is to see if one CDI module is shorting out the stop circuit of the other. Disconnect the boat harness White (early stop circuit) or Black/Yellow (later stop circuit) wires from the terminal board and separate the blue CDI stop wires. Crank the engine and see if you get spark. If you do, the good cdi has a bad circuit that is causing it to short out the others stop circuit.

Is this the test you were referring to: If readings are good, disconnect kill wire from one pack. If the dead cylinder starts firing, the problem is likely the blocking diode in the other pack. http://www.boatpartstore.com/page8.asp If so I tried that and it didnt work. If using the yellow/blue wires is a different test Ill try that. Im going to get a DVA adapter but will probably have to get it online as I have no stores near me that would carry that.

My concern now is if it is CDI related how would both of them go bad at once? Is there an underlying cause I should look for? I tried each of them on cyl 1 and 2 and both only fired cyl 1 which would mean they are both bad, is that correct? Would it be harmful to get a new CDI for cyl 1 and 2 and use one of the ones I have now for cyl 3?

Thanks for all your help, it is much appreciated.

 

[devl]

Re: 1989 85HP Force, CDI problems

I always think of one more thing after I hit reply. If the ohm tests are good is it still possible the trigger or stator could be bad? Im just having a hard time wrapping my head around 2 bad CDI boxes at the same time and if they are bad what caused it.

 

[shytownborn]

Re: 1989 85HP Force, CDI problems

sent you a private message

 

[devl]

Re: 1989 85HP Force, CDI problems

sent you a private message

Don I didnt receive it.

 

[shytownborn]

Re: 1989 85HP Force, CDI problems

should have it now

 

[john from md]

Re: 1989 85HP Force, CDI problems

CDI modules go bad because the are electronic vs electric and are more sensitive to voltage spikes. If you swapped cylinder harnesses and it still doesn't work, your issue is the module.

The stator and trigger can be ohmed out to determine if they are good or not. This resistance check is valid so if they check good, they are good.


www.esitest.com sells DVA adapters if you still want to buy one.

John

 

[CharlieB]

Re: 1989 85HP Force, CDI problems

Guys,

Ohms test only get you into the ball park.

But......

A broken winding in a coil, such as found in a trigger or a stator, CAN Ohm OK yet FAIL to generate voltage once placed under load, as in normal operation.

This is where the DVA Meter shines, the resistance used in charging the capacitor places adequate load on the coil to effectively LOAD TEST the generative capability of the coil.

No If,
Ands, or Buts about it.

Your triggers one and three are fine, but I'd bet a dime to a donut that trigger two FAILS the DVA test.

Noe there IS an alternate method of load testing a trigger but if I spelled it out here some of the guys might squawk, it works, but if done incorrectly you can let the smoke out of the trigger, then you'd be SURE it's toast.

A 1 & 1/2 V Flashlight battery and a 3 volt flashlight bulb in SERIES

If the light lights, the trigger is good, no light, it has a broken winding and will not carry the load, won't generate the voltage & current needed to trigger the CDI Box.

IF you do NOT know what a SERIES CIRCUIT IS, then go get the DVA Meter.

Oh, and your smoked meter, try changing the fuse inside before you give up and throw it away. Even the cheap Radio Shack Meters are fused inside.
(I smoke mine every couple of years, cause I'm too forgetful to switch it to the right range).

 

[devl]

Re: 1989 85HP Force, CDI problems

Thanks Charlie, sent you a PM. I already trashed the old meter and got a new one so no big deal there...need it for my cars anyways.

Don thanks for the alternative tests, will definitely try them tomorrow.

John thanks for the insight and DVA link....I hope I dont need it but will probably get it anyways for future use. This is my buddies boat but I plan to get one pretty soon so I might need all this learnin' Im receiving!