alternator locked up?

[jeremymik84]

hey guys, i have a 1996 caravelle 1750 with mercruiser 3.0 alpha one. i was showing it to a guy to sell today and it was the first crank in a while.. the battery was dead so i put it on jumper cables and it crunk fine but squealed like CRAZY!!! the alternator belt was smoking also and it was pretty dern warm near the alternator pulley. i was cranking the boat and the guy was looking so i couldnt put eyes on, but he said the alternator pulley wasnt spinning until i gave it gas to keep it from idling too low.. is there a way to check and see if its the alternator or pulley or anything else? please help!!

 

[GA_Boater]

Have you checked the belt tension?

 

[airshot]

Remove the damaged belt and try to turn the alternator by hand or a pair of pliers. If that turns ok then try the idler pulley if you have one, sounds like the bearing froze on the alternator.

 

[wrench 3]

It's not uncommon for the rotor in the alternator to rust itself to the stater if it's been sitting for a long time. If it gets spinning, it will ware the rust off. I'd still inspect the belt though.

 

[fishrdan]

^^^, Agree with the others, pull the belt and see if you can spin the alt and water pump by hand, they should spin easily, alt should spin freely with little resistance, water pump will have a bit of resistance. A couple of suggestions:
- Replace the front alt bearing if it's locked, I've replaced a few, easy, $5-10 bearing.
- Run the alt down the a auto-electric rebuilder and have them go through it.
- iBoats replacement (alt or water pump) from the Istore.
- Buy a new aftermarket (China) marine alternator.

What ever you do, DO NOT!!! put an automotive alternator on your "marine" engine.

 

[Maclin]

When the battery is dead and the engine gets jump started there is an immediate heavy load placed on the alternator. If the belt tension was getting to the loose side and or belt is worn then the belt slips and sqeaks loudly, and the alternator may end up not turning. You could see how it all behaves with a freshly charged battery.

 

[FreeBeeTony]

I had the same problem a few years back. I removed the belt, sprayed it down with WD-40 and broke it free with a wrench.

 

[wrench 3]

I had the same problem a few years back. I removed the belt, sprayed it down with WD-40 and broke it free with a wrench.

Sounds like the same thing I mentioned earlier. Once you get it turning, it cleans itself off and runs like new.

 

[gm280]

I just recently repaired the alienator on my Blazer. It would turn by hand (when I removed the belt) but was not as free as it should have been. So I opened it up and there was the problem, rear bearing was powdered. Luckily I had a few in my shop and replace it and cleaned everything else up and reassembled it. Then I took it to an auto parts store and while I watched, they tested it with load and stated it was perfect. So other then my time, it was a free fix... But those bearings are really cheap in most any parts store...