1986 Johnson 90HP VRO electrical problem.

[pochejp]

Hello everyone. This is my first post here.

This past weekend I was out on the water running my boat for the first time in 6 months. It ran very well for an hour or so at all speeds. Then while at 3/4 throttle and just cruising the motor started abruptly missing, so I slowed down to an idle. At that time the motor sounded like it was not running on all four cylinders. I tried to throttle up but it would only run at 1800 rpm's. I pulled the cowling off to see if any plug wires were off or anything obvious that would cause this problem. I pulled a plug wire and would start the motor. I did this on all four to see when a change would show up. It turns out that both of the right side cylinders were not getting any fire. So I started back to the landing only idling. I made it halfway back and the motor lost fire to the last two cylinders. Dead in the water at that point. It would still turn over like normal just didn't have any fire to the plugs.

Is this a failure of the stator? Power packs? Coils? Flywheel magnets? Voltage regulator? Ignition switch? Emergency kill switch?

What could be causing this problem? First time this has ever happened in the long and reliable life of this motor. Any info is appreciated.

Thanks,

JP

[pochejp]

Anyone?

[Boat Doc']

more than likely powerpack, remove the stop wires and check for spark to isolate the control then get a book and check the stator first.

[pochejp]

I was thinking power pack at first because the two cylinders that had no fire run off of the same pack. But when the second bank of cylinders running on the other power pack went dead it makes me think it is the source of the energy that has failed. That would be the stator. I'm going to check resistance (ohms) and DC voltage on the stator this afternoon. I have already tried the black/yellow kill wire. It still did not have any fire with that system disconnected.

Whats the chances of two power packs going out within an hour of each other? This might turn out to be a real headscratcher.

[Lou]

Power pack (s). I've had it happen to me.
After markets work fine, for me anyway.
Your a long ways from the NW. Did I miss your
story or report?:)

[Chrome Bumper]

Get the factory manual, it makes it easy to trouble shoot. The after market electronics are a lot cheaper. Find out which single component only effects those two cylinders. Pulling the flywheel and clean around and cleaning contacts might fix it, it could be some crud in a bad spot.

[pochejp]

Yea I do need to go ahead and buy a manual.

So you guys have no problems with the aftermarket parts I see. Thats good to hear because the OMC stuff is expensive as heck. I've looked at aftermarket power packs for my unit for 75.00 and a new stator for 175.00. Thats not bad at all. I'll be doing the work so I might just go ahead and change them all just for piece of mind. Being broke down on Lake Maurepas in South Louisiana in the summer is dangerous. Thats where I was when the first two cylinders lost fire. At least it idled long enough to get me back into the river before dying completly.

[Lou]

Yea I do need to go ahead and buy a manual.

So you guys have no problems with the aftermarket parts I see. Thats good to hear because the OMC stuff is expensive as heck. I've looked at aftermarket power packs for my unit for 75.00 and a new stator for 175.00. Thats not bad at all. I'll be doing the work so I might just go ahead and change them all just for piece of mind. Being broke down on Lake Maurepas in South Louisiana in the summer is dangerous. Thats where I was when the first two cylinders lost fire. At least it idled long enough to get me back into the river before dying completly.

$175 for a starter! Mine was almost $500, when I had it rebuilt for
$80. Those are good prices.

[pochejp]

OK gents the headscratching continues. I checked the ohms on the stator leads today. 595 ohms on each. Its supposed to be 400-600 ohms. So that looks ok. I turned it over to check voltage next. 149v on one bank and 170v on the other. Thats supposed to be 150+ on each bank. So that looks good too. I think the stator is good. That leads me to the power packs next. This thing has two seperate power packs that supply fire to two cylinders each. One went out first and then the other lost fire an hour or so run time later. Whats the chances of that?

I think i'll cut that kill switch black/yellow wire just to be sure its not that. Theres no way to unplug just it from the power packs because they're sealed units with only a plug.

I'll keep you guys informed.

[DJD]

OK gents the headscratching continues. I checked the ohms on the stator leads today. 595 ohms on each. Its supposed to be 400-600 ohms. So that looks ok. I turned it over to check voltage next. 149v on one bank and 170v on the other. Thats supposed to be 150+ on each bank. So that looks good too. I think the stator is good. That leads me to the power packs next. This thing has two seperate power packs that supply fire to two cylinders each. One went out first and then the other lost fire an hour or so run time later. Whats the chances of that?

I think i'll cut that kill switch black/yellow wire just to be sure its not that. Theres no way to unplug just it from the power packs because they're sealed units with only a plug.

I'll keep you guys informed. When I lost the stator on my 115 v-4 the motor ran fine until it heated up and then lost all spark. After it cooled off it would run again Just my 2 cents DJD

[pochejp]

Hello everyone. This is my first post here.

This past weekend I was out on the water running my boat for the first time in 6 months. It ran very well for an hour or so at all speeds. Then while at 3/4 throttle and just cruising the motor started abruptly missing, so I slowed down to an idle. At that time the motor sounded like it was not running on all four cylinders. I tried to throttle up but it would only run at 1800 rpm's. I pulled the cowling off to see if any plug wires were off or anything obvious that would cause this problem. I pulled a plug wire and would start the motor. I did this on all four to see when a change would show up. It turns out that both of the right side cylinders were not getting any fire. So I started back to the landing only idling. I made it halfway back and the motor lost fire to the last two cylinders. Dead in the water at that point. It would still turn over like normal just didn't have any fire to the plugs.

Is this a failure of the stator? Power packs? Coils? Flywheel magnets? Voltage regulator? Ignition switch? Emergency kill switch?

What could be causing this problem? First time this has ever happened in the long and reliable life of this motor. Any info is appreciated.

Thanks,

JP

[pochejp]

Well the problem has been found. After much troubleshooting and checking I have found the problem.

Both power packs failed. Replaced both and the motor runs great. Everything is working fine. Stator, trigger, voltage regulator and now power packs. I bought a used one first from a local boat repair shop for 40 bucks and tried it. After it worked I bought two new ones and installed. It runs better than it has in years. Got a spare now too.

Thanks for all your ideas and comments. Very helpful.

Good day.

JP

[Hunt'nFish]

Good to hear your back up and on the water.
Now, what brought you to IFish all the way from Louisiana?....how did you find IFish?
Welcome aboard.
Hunt'nFish