One more alternator question (F-L 120)...

[Tazling]

Still trying to figure out what killed my alternator.

When I started investigating the problem I found that the drive belt was quite loose (as in, I could turn the alt easily by hand without the belt moving). This was totally my bad, as the alt was a new install about a year ago and I know that drive belts stretch so I should have checked it a couple of times. But there was other bigger stuff going on with the engine last spring (head gasket job) that distracted me.

So here's the question: can a loose belt (with increasing slippage over time) cause alternator burnout?

I really am hoping to find some simple and immediate cause that doesn't involve a long, frustrating search for some subtle flaw in the larger electrical system

I will have to replace it no matter what, so... is there a preferred brand of alternators for Ford Lehman 120's?

 

[Cigatoo]

40 years in and around auto service business. Never heard of a loose belt ruining an alternator. I would tighten the belt and test the charging system / battery as a whole before replacing anything. Maybe something else loose? Connections?

 

[Tazling]

40 years in and around auto service business. Never heard of a loose belt ruining an alternator. I would tighten the belt and test the charging system / battery as a whole before replacing anything. Maybe something else loose? Connections?

thanks, that's not the answer I would have preferred but it's a good solid answer. eliminating one thing after another, eventually I may figure out what's the real problem!

 

[C lectric]

I have HEARD of loose belts heating an alternator to the point the alt. fails.
Long time ago and no experience with it pesonally but maybe ask at an alternator rebuild shop.

Odd though that the belt and alt. also would not be hot and stinking of burned rubber and wiring. But ask.

 

[jwag956]

My understanding is that if an alternator doesn't have anything to charge - it will burn out. How does that happen? - (master) battery switch turned off or in our case, on our GB - the shunt that feeds the amp meter at the helm was burned out (like melted).

 

[socalrider]

How do you know the alternator is dead?

You may be able to get an alternator shop to rebuild it for pretty small $$.

Alternatively you could source a replacement - but also consider upgrading depending on how the rest of your systems are configured. We dropped in a nice externally regulated Balmar which wasn't cheap but provides a very valuable high current (100a+) charging source to augment solar on our non-generator boat.