Alternator Reliability

[Paul Bennett]

I've seen several postings re: Powermaster Alternators working well yet quitting after a few years.

I'm wondering if high belt pressure causes front bearing failure. Any thoughts? or Alternative Alternators?

Should bearing failure indeed be a problem...has anyone found a solution?

 

[51 MERC-CT]

Which model are you referring to ?
Have been running a GM alternator for over 20 years with no issues.

 

[PeteVS]

Is it possible that an aftermarket alternator could be using low grade bearings to shave his costs to boost profit? Maybe it would be wise to buy an alternator and replace the bearing with a better quality piece from the get go. The fact that alternators carry only a low current through the brushes and those brushes contact a non-segmented rotating surface is what makes the alternator such a clear cut choice over a generator. You should also cut bearing load by reducing belt tension to only what is required at high charging currents.

 

[JSeery]

I've seen several postings re: Powermaster Alternators working well yet quitting after a few years.

I'm wondering if high belt pressure causes front bearing failure. Any thoughts? or Alternative Alternators?

Should bearing failure indeed be a problem...has anyone found a solution?

I'm currently using a Whitney alternator conversion, but haven't had it long enough to comment on life expectancy.

 

[Bob/Pa]

Like Merc-51 been using for over 10 years, no problem, first one I used new had a humming noise so Powermaster sent me a new one and still going strong.

 

[adileo]

I have a 6v powermaster alt. In my 39 for over four years. No problems yet.

As for tight belt, I’d be more concerned with water pumps, than the alt.

 

[Ggmac]

13 yrs and no problem. Dang it seems like just yesterday .

 

[drolston]

I ran a PowerMaster 12 volt generator-look-alike alternator which burned out after less than three thousand miles. The wiring and diodes failed, not the bearings. That look-alike alternator is really a small car alternator stuffed inside of the look-alike case. Probably does not ventilate as well as it should. I got it repaired by a good alternator shop, but do not expect long life from it.

 

[G.M.]

Which model are you referring to ?
Have been running a GM alternator for over 20 years with no issues.

I had several GM alternators converted to 6 volts. The electric
motor company, Chestnut Hill Electric near Lancaster, Pa. suggested
they use a 24 volt stator and 6 volt diodes and an adjustable
voltage regulator. This allowed it to provide 7.2 volts at idle with
a LARGE 39 Ford pulley. On the 7 alternators I made the adjustable
voltage regulator was mounted inside the rear cover plate with a
hole through the cover plate to adjust the idle voltage. I had two of
them made 10 or more years ago and they still work good. We used
a 39 Ford front generator mount with the big bearing and had to
make a shaft adaptor for the front of the shaft for the pulley to mount
on. The last picture shows the long term end results of an over tight
fan belt. This pump was of a 35 Ford that belonged to a friend of
mines father. The two end covers were 2 of seven alternators I made
a number of years ago and all seven still work good. G.M.