Outboard question but not antique

[billw]

Maybe some of you long time OMC techs can answer me a question. It’s been about 12 years since I worked nearly every day on outboards of all brands. I seem to have forgotten a few things…..

I was helping out a neighbor tonight, with his 80s vintage Johnson cross flow 150 V6. In the process of getting it going after 3 years, I did the carbs and ran it on a flusher. Seemed decent, so after another 4-6 weeks of sitting idle, we finally took it to the lake, tonight. It was very tough to start, with a lot of smoke. I figured it was the VRO thing but then it started to kick like ignition, then the whole port bank went out. NO spark at all. I pulled the stop wires off both packs; no change. I went back to the house and pulled out two different peak reading volt meters. I made a break-out harness for the charge coils and tested the charge coil output. BOTH charge coils PEGGED both peak reading volt meters. This is like over 500 volts, if you believe one meter and over 400 if you believe the other. The engine runs half way decent on the starboard bank, at the dock, even with all three port plug wires hanging off.

I thought charge coil voltage was like 180 to 280 or something like that….not over 400! But it’s the same on both sides, triggers test good, so I am going with a bad pack….but over 400 volts???What am I missing or forgetting?

Long live American manufacturing!

[beerman57]

I’m far from an expert, but a quick, easy test is to swap power packs. If that doesn’t show a bad power pack, then it’s the stator or trigger.

[frankr]

I know you aren’t having a Duh! moment, and have the meters set to an appropriate range, right?

[billw]

quote FrankR:

I know you aren’t having a Duh! moment, and have the meters set to an appropriate range, right?

Ha ha, yeah, I have plenty of duh moments; but this isn’t one of them…..The Mercotronic was set on 500 and the little ES (Mercury) DVA meter was set on its max of 400. Interestingly, this same neighbor also has a 1989 70 Johnson. Just this past Sunday, he couldn’t start it after sitting all winter. NO spark. That was a charge coil, failed open and my meters worked perfectly to find that problem quickly. He had a spare engine, we robbed the stator off it and the 70 is now running fine. I even tested the output of the second stator, when I put it on and it was around 280ish, just what I would have expected.

I don’t know for a fact, what the charge coil output is supposed to be on this 150 model….and since the motor was actually running on the stbd. bank, my output was not cranking voltage but RUNNING voltage….However, I have still never seen that much on anybody’s brand of outboard.

I do know I could swap packs but my concern is that the charge coil’s high output might have ruined the non-firing pack…..and I don’t want to keep messing around until I smoke the other one…..

I seem to get more than my share of weird problems. I can’t imagine how the two separate coils could somehow have shorted so that they are working in phase to produce double the peak voltage they are supposed too…???? I wish I had another stator laying around to try; but they are not cheap.

Long live American manufacturing!

[fleetwin]

Well, let’s start at the beginning. What year 150 is this engine? Does it have the 35amp alternator, or the standard 12 amp system?
Did you check the charge coils with an ohm meter? Is there any chance that parts have been mismatched/swapped around? In other words, did someone put a 12 amp stator under a 35 amp flywheel or vica versa? It seems unlikely that both charge coils failed in the same manner, but anything is possible.
Like Frank says, meters are always suspect. All the settings changed in the late 80s, so it is easy to get fooled.
Finally, you mention isolating the powerpack stop circuits, I just want to ensure you did this completely. In other words, pushing both powerpack stop leads out of their rubber connectors. Simply unplugging the Big red connector will not isolate the packs from each other.

[billw]

I will get you the year….I never did look yet. It does NOT have SLOW or quick-start. That much I know. My guess is 1987.

This engine was supposed to be running great a few years ago, when it got put away without proper winterizing. A few years ago, it had the problem where the lower mounts swell up and make the shift shaft bind in the swivel tube. At that time, I torched it all apart for him and put in new mounts. It was running good then and nobody else has touched it since. So, I don’t see the wrong flywheel or stator being possible…but good idea.

I am using two separate, peak-reading voltmeters that worked perfectly and equally, last Sunday. The same two meters, on the low voltage scale, tested the triggers, er, I mean SENSORS, just fine. I did NOT ohm out the charge coils yet. I didn’t think of it until we were already done for the night. I will do that.

It has the type of packs where each pack has its own single-pin-plug stop wire. I don’t need to back a pin out of an Amhenol connector because each stop wire is by itself. I know the ones you mean, though.

I forgot to mention that I remembered some of the Sea Drives wearing away the wires coming out of the back of the packs, against the block. I checked for wear, grounded the pack and left it hanging off as a test. Still no spark.

I am 99% convinced I have a bad pack; but it’s the high charge coil voltage that concerns me.

Long live American manufacturing!

[mercuryman]

Sounds like a good reason to stick with old motors, points and coil simple.

[Casey Lynn]

What a coincidence. An old dealer of mine called today to troubleshoot the engine below.
V4 Cross flow….mid 80s or higher.
Extremely high charge coil output at cranking speed and a failed pack. The pack that failed on his engine is a CDi pack and now has a swollen section in the pack. Cranking charge coil voltage was 280-300v at cranking. No shorts to ground and no opens.
Off the top of my head the output at cranking on that particular engine should be in the 180-200v range or higher and we typically see a bit over 300v at running speeds. I don’t know what the safe upper threshold for the capacitors in the packs is but it would seem to me that 400-500v would be excessive and this mechanic said that running voltages were pegging his meter as well. The meter is a known good meter.
He is installing a known good stator and should get back to me tomorrow or so and let me know what the new voltage is.

As a side note this engine came in to him a couple weeks ago with an extremely high idle. In troubleshooting it was found that the timing was almost exactly 30degrees advanced with no loose flywheel/key failure and the hub on the flywheel had not moved. A separate flywheel and timer base had been substituted with no change in idle timing. The only part that was not changed was the stator, mentioned above, with the high output.
Finally, the flywheel was indexed and installed minus the key at a 30degree retarded position, proper advance was checked, and he gave the engine back to the customer. Now, before some of you try and sound an alarm about that last procedure just remember that the key simply initially locates the flywheel. Once properly torqued it serves no purpose. There was no unlimited money supply to repair the engine and the mechanic had a ton of free time in it already. Will be interesting to see if the stator output change will affect the timing.

[Casey Lynn]

quote mercuryman:

Sounds like a good reason to stick with old motors, points and coil simple.

Rather run a CD ignition any day of the week. Simple as well and after an extended down time it still works.
We do run into the occasional challenge and those can be fun.

[billw]

That is too funny! I can’t wait to hear what the mechanic finds…..Thanks so much for that post! I was feeling like I was loosing it…..If he puts a known good stator in and finds that his voltages drop to normal, I will do the same. It’s just that my neighbor is trying to sell this boat because now he has TWO girls in college; so experimenting with a new, expensive part is not really an option.

For the record, this 150 didn’t seem to have a high idle, before (a few years ago) or after the pack let go. Also, the way this engine idled reasonably well in neutral, on three cylinders is not that unusual, in my experience. THAT much, I HAVE seen before. (It’s pretty cool, actually.) So I am kind of assuming my timing is okay, for now.

I like CDI better than points and condensers, too. Unlike points and condensers, you usually don’t have to pull the flywheel to troubleshoot them. With the right meters and a logical process, they are usually pretty easy and quick to figure out. This is an exception.

Fleetwin, to answer one of your questions, now that I think about it, it must have the 12 amp stator because the flywheel is solid with no ventalation on top. 35 amp stators had ventalation, right? Not sure I ever saw one of those on a 150 but maybe they had them….

Long live American manufacturing!

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