Balmar alternator

[wgstrebel]

Hello all,
I purchased a 65 amp Balmar alternator with regulator a couple years ago and decided to get around to installing it. Therein lies the issue I ran into. The alternator mounted properly to the bracket but when I went to tension the belt something was providing resistance such that I could not move the belt to rotate the cooling fan. As it turns out, the cooling fan was hitting the mounting bracket on the engine. It seems that the fan blades protrude about 1/16" too far such that they hit the bracket keeping it from spinning (lucky I didn't try and start the engine - ouch that would have hurt). Either I was installing it incorrectly (quite possible) or there is some trick that I am unaware of to install it correctly. Fortunately the old alternator is still functioning fine. But it seems sad to let a perfectly good (and expensive) alternator sit in my basement unused (plus provide ample fodder for my wife to ask why I have so many "extra" boat parts just sitting around.

I have a late model A4 and as far as I know, the bracket / lifting eye plate is the original (I was only 2 when the boat was built - so who knows if it is "original"!)

Any advice is greatly appreciated.

[tenders]

I had a similar problem with the 120 amp alternator earlier this season. What I found was that if I put a little more serious tension on the belt, it moved the alternator far enough out of the way of the bracket--but just barely. I then used a Dremel to file off about a 1/16" of the corner of the bracket to give it some more breathing room.

It's also possible that a belt 1" longer than the stock would stop this from happening too but I didn't try that.

[policecentral]

Add a nut?

How about putting a screwing a nut on the tension bolt between the tension arm and the alternator to serve as a spacer?

JSM

[wgstrebel]

Thanks for the advice. I thought about filing down the bracket, but was reluctant just in case I was doing something wrong to begin with. I have wrecked many an otherwise well engineered apparatus due to my hastiness. I'll try the other suggestions prior to letting the sparks fly.

Many thanks.

[tenders]

> I have wrecked many an otherwise well engineered apparatus

You and me both. But rounding off the corner of a square bracket (which is what I'm talking about) wasn't one of those situations.

To get maximum tension on the belt I stand a small crescent wrench on end, jaws up, and wedge the curve of it up underneath the alternator. The bottom of the crescent wrench rests on the engine between the starter and the water pump. Then I tighten the bolt on the tension arm, and finally the pivot bolt. That got my alternator a couple of thousandths off the bracket, and the Dremel work was for peace of mind.

I'm not sure I understand policecentral's suggestion. Extending the bolt on the tension arm would twist (or try to twist) the alternator so it wouldn't be parallel to the plane of the belt.

[Jesse Delanoy]

Indigo makes a great device for adjusting the alternator mounting to get proper belt tension. Look in their website, inside the link for their fresh water cooling apparatus.

[policecentral]

Another try...

As I understand your problem, the tension arm is too close to the alternator cooling vanes and it interferes with rotation of the alternator.

My suggestion is to place a spacer -- a nut or a couple of washers -- in-between the tension arm and the threaded bolt hole in on the alternator. This would effectively move the tension arm aft and away from the alternator vanes; thus giving you the needed clearance. You would tighten the bolt as usual when you have proper belt tension. The tension arm itself is flexible enough to easily move aft to accommodate the spacer.

The tension bar is not a structural element, it merely elevates the alternator to maintain proper belt tension.

Sure seems easier to me than trying to cut down the size of all of those vanes. You could try this in about 10 minutes (and then go sailing -- which is the point of all this, true??) as compared to spending the day redoing the vanes...

JSM

[msauntry]

Just use a longer belt!

No grinding or special tensioners needed. Overtensioned belts cause problems.