Balmar alternators overheating

[hellosailor]

"Straight edge shows at least 1/16 off at the alternator."
The most common misalignment is probably if the alternator pulley is pressed too deeply (or not deeply enough) on the shaft, so it is "in front of" or behind the plane of the main pulley. If that is the case with your alternator pulley, the solution is often to have the pulley shimmed or pressed into the proper position. DO NOT use a hammer if you need to press it further in, this will damage the bearings.
Sometimes the alternator feet are mismatched, and you can use shim washers to move the entire alternator forward/back on the engine in order to match up the pulley as well.

The question is...which way are you out of alignment? And then, to see what the "wrong" thing is. Sometimes someone has kludged up a mounting arm that just isn't right, or bends under tension. Sometimes you'll even find a pulley, shim, or fan blade set installed "backwards" or in the wrong sequence. Anything's possible.

For extra points, while you're in there:
Measure the alternator pulley size, and the main crank pulley size. Get the specs on the alternator output, and now compare the alternator's speed at "charging" "cruising" and "battle" speed to the manufacturer's recommended speeds for optimum charging, and maximum speed. Sometimes the pulley itself is simply wrong for the installation, but chosen because it was 'good enough" and a stock part.

[James S]

Zena makes high output alternators that sound pretty darn skookum.
Well worth a look
www.zena.net

[Nauticatarcher]

Originally Posted by gettinthere

Could you give more details?

I did a google search and received an enormous array of automotive bosch alternators. Way too many to sort through.

Also, I want drop in capability in replacing my Balmar so I can keep the Balmar 75 as back up with quick replacement.

here is photo of alternator
Bosch catalogue number is BXU12121A

[captchetco]

Another bit of info. Balmar used to make cooling fins for one direction or the other, and the universal one. I took off the universal and put one for the correct rotation, and it solved the problem. Wasn't expensive. Balmar alternator has been working fine for 12 years, Until: I had it worked on New bushings as a precautionary move. I reinstalled it and it worked fine for awhile. Started putting out reduced power, and I noticed sparks coming from the output terminal. Appearently it had not been reset on the case properly when worked on. Now it needs new diodes.