Charging 85 hp 1972–upgrade stator?

[fleetwin]

amuller wrote:

Yes, that’s the kit I was looking at. And the stator is only $20, so I might order one. There are various rectifier numbers, with varying numbers of leads and some claiming to be “regulated” and some not. Sometimes there is a separate regulator, sometimes not. Is the kit intended to be used with a rectifier, a clipper, and a regulator? Hard to tell without the instruction sheet for the kit. Some sources recommend removing the clipper as doing more harm than good…. Then there is the advice to NOT use sealed batteries, which are pretty much the only type readily available these days. This kind of makes sense when the charging source is unregulated, as water will be boiled out of the battery and not readily replaced.

Well, in this case, if using the “kit”, the clipper and the regulator seem “redundant”, so I would be shocked if the instructions did not advise removing the clipper. But, keep in mind, that this kit is old, and so are the instructions. The regulator in the kit does the job of the “clipper”, which is really only a simple regulator….
And yes, would definitely use a refillable battery. There won’t be much draw on this higher output system, and the “regulator” will only cut the output in half….I would probably install a voltmeter in the dash….I would skip the ammeter because the wiring is so messy….You have to disconnect the rectifier output lead, then run a lead up to the ammeter, along with another lead coming back to the engine/battery…Messy, and problematic…

[amuller]

As far as I know marineengine has some of the pieces but isn’t offering the whole kit.

Wiring a direct reading ammeter would be a pain but wiring in a shunt isn’t such a big deal. But of course then you have to decide where to put it. Do you want to know the alternator output, or the net charge into and out of the battery…..? I’m for the most part satisfied with a good voltmeter. Easier to install and gives a direct warning of overvoltage, in which case turn on some loads.

By the way, I picked up a (free!) ’72 100 hp parts motor (quite likely could be a runner) and I see it has a breakerless ignition. Of course it uses a different CD box–one even more expensive–but does anybody know if the breakerless ignition can be installed on a point-ignition motor? And how it compares in reliability?

[frankr]

Pretty sure it would have a different crankshaft, cam for points, vs key for notched timer rotor. But I haven’t actually looked it up.

OK, Motorola Amplifier (breaker points) vs Prestolite (breakerless) Pulse Pack. They are pretty similar in the way they work, except for the triggering method. Both systems use that POS distributor cap. The Prestolite had a nasty habit of suddenly stopping dead in the middle of nowhere and working just fine by the time you got it towed in. I found it hard to like for that reason. On the other hand the Motorola system had the points. I don’t see that as a big problem because the distributor required maintenance service anyway. The points themselves never burn and pit their contacts like “regular” breaker points. But with many hours running they wear mechanically just from opening and closing a few million times.

So it is mostly a matter of choice and opinion. My personal choice would be the Motorola. Matter of fact I had a new one on my own boat back in “The Day”, and it never gave a bit of trouble.

[amuller]

Thanks, frank. This motor isn’t idling properly–it sneezes and revs up and down. I have no evidence but my gut feeling is that it’s the POS distributor. I looked for carbon tracks and other obvious stuff when I had it open and didn’t see anything. I can try to localize it to a cylinder, but aside from that, what should I look for?

This ignition kinda seems like the worst of all words–potentially troublesome and expensive CD box, and POS mechanical distributor. I like the old 4 cylinder West Bend ignition: four point sets, mounted at 90 degrees, each firing it’s own coil. No electronics. No distributor. I suspect if I got motivated I could gin one up.

[amuller]

I spent a few minutes comparing part numbers on marineengine.com. *IF* they are correct (as they generally are) the crank, crankcase, flywheel, charging stator, etc are the same. Only the timer base and the electricals are different. Plus the triggering rotor of course. So it *should* be possible to swap the systems.

[glastron71]

Hi. Just found this post. I have a 71 Johnson 125. I am having an issue with the motor running only when I have had the battery charging over night. After about 15 -20 mins it will begins to start missing. The shift diodes and rectifier were bad. I also have a new CDI box. I’ve replaced those with the same issue. The stator checks good. The battery does charge. But only at high rpm’s. I am wondering if this 15 amp stator will work on a 71. I’ve looked up the part number for the 9amp and it’s the same between the years. I can not find an original stator any were. Thanks.

[amuller]

Sounds to me as if you have a weak battery. If the only draw is the ignition, and the battery is in good condition and fully charged, it should last for a lot longer than 15-20 minutes.

Does your motor have the breakerless ignition or the double-point ignition?

Check the voltage at the feed to the CDI box, and see at what voltage things start to go to pot. Compare that to the voltage at the battery terminals.

In general, my experience is that old motors/boats tend to have rats nest wiring and there might be a high resistance somewhere.

I expect the higher-amp stator would work on your motor, but if you have checked it for shorts and opens it probably isn’t your problem.

I still don’t have mine sorted, because I’m too distracted with other projects to get to it.

[glastron71]

It’s a new battery. I have 12 volts at the CDI. It doesn’t have points. I have 8 volt ac on both wires off the stator at idle.

[glastron71]

It also has a hard time starting. I have to jumper the ign wire to the battery wire. If I remove the jumper it dies. But after it been running and remove the jumper it stays running and will start normally.

[frankr]

glastron71, you are hacking onto another topic. That only causes confusion.

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