speaking of stators........

[Tuck_72]

.........what amp stator is required for 1975 150hp.....serial 4124419..This is the 2 wire one

 

[ricksrster]

Re: speaking of stators........

The part # is 398-4793 or CDI after market replacement 174-4793. I believe they put out 12 -14 amps.

 

[Chris1956]

Re: speaking of stators........

Tuck, I had thought they were more like 6 Amp Stators. They are enough to charge the battery some, and run the ignition.

 

[Tuck_72]

Re: speaking of stators........

I wanted to get one that works, but not willing to pay $285 for a new one......Had an idea......Don't think I am a hack or a nut, but I work on harleys and own one I built...Powered by an 89 model big twin 80 ci motor....The stator ($34.95) in it as well as a 89 or a 90 model sportster stator ($34.95) looks the same, bolts on the same and is the same OD in so it will fit inside the flywheel, as this 75 merc stator does....It has 2 wires as well......If I used the correct sportster regulator ($47.95) or one for the big twin ($47.95) along with it, it should charge the battery with 13.5 to 14 volts as it does the bike, yes? Makes sense on paper.....The one for a sportster is a 19 amp and the big twin is 32 amp BUT, if it charges the battery with 13.5 v, what would or does the higher amp rate do even if it charges with the same volt output to the battery? On the bike I run a headlight and tail light/brake light and power a coil with points ignition only.....Nothing else on it.........

BTW........This motor will run without a stator connected....1975 150hp inline 6 Distributor motor8) yea!!

 

[Silvertip]

Re: speaking of stators........

The higher amperage will have no effect on anything. A higher amperage stator will simply charge the battery faster than the stator with lesser capability. It will also allow running far more accessories and still keep up with the electrical demand than a stator with lesser output.

 

[jddenham]

Re: speaking of stators........

There are two stators available for your 1975 Merc1500cc motor. One is a low output <10amp for models w/o trim/tilt. The other is a 15-16amp for motors with trim/tilt.

Makes more sense, need more battery/power to operate the trim/tilt!

 

[jddenham]

Re: speaking of stators........

Oops, I just realized something. I was thinking of Johnson motors:

http://www.tenkillermarine.com/boatparts/jandesearch.asp?cat=items&cval=4&hval=37&val=49

Not sure if the same applies to your merc. That's what I get for owning both!

 

[AMD Rules]

Re: speaking of stators........

If it were my motor, I would be hesitant to hook up a 'home-made' solution. The electricals for the vintage Mercs are getting harder and harder to come by, and cooking a switchbox accidentally could be financially frustrating. I believe from what I have read, if you install a newer higher amp CDI stator, you also need to install a voltage regulator. I could be out in left field.

 

[Chris1956]

Re: speaking of stators........

Tuck, You could go with a used stator. Since the same stator was used in all the distributor ignition 4 and 6 cylinder inlines, they are fairly common. I also found them to be fairly tough as well. They are also easy to test with a volt/ohmmeter. You should see a few ohms resistance(not quite a dead short) across the two wires, and infinite resistance from the wires to the metal core.

If you do decide to go with the Harley solution, I think the risk is in the physical fit and number and strength of the magnets. If you can get it to fit and charge a few amps (DC) I think you will be OK.

You may not need the regulator, as the original system was unregulated. The battery acted as a load and absorbed any excess current (same as my '73 Yamaha enduro motorcycle). You do need a 25A full wave (bridge) rectifier, if your original rectifier is bad (likely), which is available from Radio Shack for less than $5.

 

[Tuck_72]

Re: speaking of stators........

Well, all of the used ones I have read 0.00 ohms between the wires BUT, my meter is not the high $$ one......Guys at work say the cheaper, $20 meters might not be accurate down to that low of a reading .....All have infinite resistance from the wires to the core....With a good meter what should it read wire to wire set on 20k....BTW, the harley stator reads 0.00 ohms on my bike and it charges great....

 

[j_martin]

Re: speaking of stators........

Wire to wire on 20 K range would be essentially 0. The actual resistance is probably less than an ohm. Could be a couple of ohms, but no more.

Maybe your original one is good and the rectifier is bad.

 

[Chris1956]

Re: speaking of stators........

Tuck, Those cheaper volt/ohm meters can be pretty inaccurate. I had one that could not tell the difference between a dead short and 75 ohms resistance. After I found that out, I only used it as a continuity meter.

 

[jhebert]

Re: speaking of stators........

The current and voltage output from a permanent magnet alternator is proportional to:

--the number and strength of the magnets
--the number of coils and the number of windings in the coils
--the rotational speed of the engine

Even though the two stators may appear similar, they may not necessary produce the same output. The number of magnets and the strength of those magnets will affect the output.

More details of permanent magnet alternators can be found in

http://continuouswave.com/whaler/reference/PMA.html

--jhebert