mercruiser 120 bracket question

[rpatton]

Hi guys.has anyone had any issues with the alternater adjustment bracket arm cracking at the thin part of the adjustment slot. This will be my forth time replacing the bracket. Is this a common problem . the boat is a 1986 mercruiser 120 . thanks

 

[JustJason]

Re: mercruiser 120 bracket question

Yes, they do crack. When adjusting your tension use a belt tension deflection tool or else you will keep on cracking them. The belt does not need to be as tight as most people think. It only needs to be tight enough to not squeal, and that's it.

 

[fishrdan]

Re: mercruiser 120 bracket question

Do you make sure the bottom bracket bolt is tightened after the alternator belt is tensioned? If it's loose the alt can wiggle around.

I'd check the pulleys to make sure they are running true and straight. (I had to replace the waterpump pulley on my 140HP since it was tweaked...)