79 Evinrude (85hp) - Coil doesn't fire when cold

CaneCutter79

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(My motor model and type is in my signature below)

The last few trips, my motor acts as if a plug is fouled when cold but only initial start (in winter, cold water).
Today, I ran the motor on the hose and checked eached coil with a timing light. Only the #2 cylinder is not firing. It's not the plug because the power source to plug is from the coil and I would have fire if the coil was doing it's job.

I changed the coil to an older "backup coil" but it only fired once. No intermittent flashing from the timing gun. This told me it's not the coil but either the CDI power pack or the trigger. I have recently changed the stator with a brand new stator so it's not that.

This issue would happen on rare occasions even when motor was warm. Motor would lug and not fire on all cylinders. Then when you try to get on plane, it would lug for a few seconds and then take off like normal. I figured it was a fouling plug. Now, I know it's probably a failing pack about to go or the trigger.

I'm going to swap power packs from one side to the other to see if the problem moves. If so, I'll know which pack is bad and that it IS the pack and not the trigger. If problem stays, it's probably the trigger. Could be a lose connection for all I know and a simple/easy fix.


Has anyone heard of this before? It's consistent when the motor is cold, completely inconsistent when motor is warm. Very rare when motor is warm for that matter. When it's warm, motor runs great.
 

racerone

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

Rig up some sort of tester so that you can check for spark intensity.----Spark when good on that motor will jump a gap of 7/16" or more.
 

emdsapmgr

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

Good call: Switching the identical power packs is a good test. If the "no spark" condition moves to the other head when the packs are swapped, replace the bad pack. If that does not fix it, the timer base would be the next item to check. (you can measure it's output voltage output when cranking.) Weak ignition components tend to run better when cold, then fail once the engine heats up to normal operating temps.
 

CaneCutter79

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

Weak ignition components tend to run better when cold, then fail once the engine heats up to normal operating temps.
That's what I've always heard. This seems the opposite in this case. Which is rather odd. Seems like I read once that a bad pack will act like this when cold and operate fine when warm.


I've already done the spark test by the way. This is getting no spark on #2. When running correctly, spark jumps gap but this cylinder is a few degrees cooler than others. The cylinder below is also colder by 1-2 degrees which leads me to believe it's the pack if both cylinders on one side of the boat are colder than the other side.

A swap of packs will determine if one is bad.

If not the pack, is there a way to test the timer base/trigger?
 

emdsapmgr

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

Yes. You'll need a special "peak reading" voltmeter. If you go to this website: cdielectronics.com, you will find the appropriate specs for your timer base. When cranking, your special voltmeter should read somewhere in the 0.3 to 0.6 (depending on year) volts. The real number should be listed in their troubleshooting guide. If output is less that that nominal voltage and it's condemned.
 

CaneCutter79

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

I've got a DVA adapter. Will that work for this? It's a special too that you connect to the end of a standard meter and it supposedly converts the voltsge to read like a DVA meter.
 

AlTn

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

yep..that's what you'll need
 

emdsapmgr

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

That should do it. See what cranking voltages you read with the adapter..
 

CaneCutter79

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

I never did get the adaptor to pickup a reading. Not sure why. Got frustrated so I swapped the packs from one side to the other and made note of which plug wire did not get fire to check for spark on that plug on the other side. Sure enough, the problem moved with the pack to the other side of the motor which told me it was definitely a power pack issue and not coil, timer base trigger, etc.

Ordered a new pack and I'll be back better in business. I'll fiddle with the adaptor one day when I have time. Thanks for the help guys! As always, a great resource of information!
 

emdsapmgr

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

You got some valid results from your test/swap.
 

boobie

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

Keep us posted with the end results when you get the new pack on.
 

CaneCutter79

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

Ok, I received my new pack today.
Anyone ever heard anything about ArielTek as a part manufacturer? Seems like they are more for personal water craft than OEM marine parts.

The description on Ebay was "New Johnson Evinrude CDI Power Pack 582684 581805 582125". Technically, "CDI" is correct because the motor is a coil distributed ignition (I think I have that right) but I was led to believe that CDI was the manufacturer of the part. Not ArielTek. After looking at the photo on my ebay listing, it clearly shows "ArielTek" in fine print. I saw a blue pack, description said CDI, so I thought it was a CDI replacement part. I can't fault the seller on ebay for my mistake although it does seem a bit deceptive.

My only concern is if the part I have is any good. I'm sure it will work fine, I just don't want it catching on fire or going bad within a year because I got the wrong part.
 

racerone

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

-----------Would it be ----Capacitor Discharge Ignition----
 

CaneCutter79

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

Possible. ;-) I knew I didn't have it correct or fully correct but you knew what I was driving at.

I just want to make sure the part I have is not simply put..........."a piece of junk". Seems OK from a glance and it supposedly was inspected. It has an inspection sticker on it.
 

boobie

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

Why didn't you buy it right here at I-Boats rather than **** around with some off brand ?? Good luck.:watermelon:
 
Last edited:

CaneCutter79

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

Why didn't you buy it right here at I-Boats rather than **** around with some off brand ?? Good luck.:watermelon:

I know. I think I got too focused on the part number, looking up prices for comparison and the one I got was $20 less. I thought I had looked it up on iboats but I don't recall if I found it here. I just looked it up and found it so I know iboats has it. I typically order from here when possible. Like I said, I "thought" I was getting an actual CDI power pack.


Lessons learned.......
 

CaneCutter79

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

Well, new part solved problem. Fires cold with no problems. Smooth running.
 

boobie

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

Well, glad you got it fixed.
 

CaneCutter79

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Re: 79 Evinrude (85hp) - Coil doesn't fire when cold

Well, glad you got it fixed.
Thank you. And thank you for your help!


Now if I could just get a reading on my DVA adapter. I gotta learn how to use that thing.
 
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