What is it with 3.0 Mercruisers eating alternator belts?

[mark1905]

Just brought home my second 18' BR with a 3.0 Mercruiser, and am having the same exact problem that I did with my last one: It eats the alternator belt.

What is it with these engines that makes them do this?

The pulleys are fine.. not rusted. Everything in alignment. Not over or under tightened belt. Front belt is fine... just the dang rear belt.

Still yet, it takes total vigilance to keep it tight.. It wears it skinny and sucks it down and down into the pulleys and requires re tightening all the time until it just plain wears it out. Front belt is fine... just the dang rear belt.


Any suggestions or input?

 

[Don S]

Re: What is it with 3.0 Mercruisers eating alternator belts?

Probably rusty pulleys. Rusty pulleys acts just like sand paper and quickly grinds them down to nothing.
Sand and paint the pulleys and keep them that way and the belts will last.

 

[chiefalen]

Re: What is it with 3.0 Mercruisers eating alternator belts?

the bottom pulley hows that one.also the alternator could be freezin up burning your belts.is there any black stuff in your engine bay?smell that belt burning?if it aint the alternator than do what don says take the pulleys off sand them smoother than a babys butt paint them black and put them back or new belt and put another one around the bolts so if one goes when ya on the water all u will need is a 1/2 wrench with a piece of pipe to put the new belt on.