3.0 belts always breaking

[loie587]

I have 2 friends that have Bayliners with 3.0 Mercruiser I/O. Me and another guy I work with which are both auto mechanics for more than 20 years experience each keep up with the maintence on these boats. Anyway last boat season these 2 boats went thru belts like crazy almost every 2 times we went out they would break. Nothing locked up and all the pulleys seem to be lined up. Just dont get it. anyway my ? is do they make some kind of tensioner that can be installed to help keep the altenator tighter to keep the belt tighter. Or is there any thing people know about that we dont. Thank You

 

[Bondo]

Re: 3.0 belts always breaking

I have 2 friends that have Bayliners with 3.0 Mercruiser I/O. Me and another guy I work with which are both auto mechanics for more than 20 years experience each keep up with the maintence on these boats. Anyway last boat season these 2 boats went thru belts like crazy almost every 2 times we went out they would break. Nothing locked up and all the pulleys seem to be lined up. Just dont get it. anyway my ? is do they make some kind of tensioner that can be installed to help keep the altenator tighter to keep the belt tighter. Or is there any thing people know about that we dont. Thank You

Ayuh,.... Welcome Aboard,.... The Biggest Killer of belts on boat motors is Rusty Pulleys,...

The alternator swings, which tightens the belt,... No idler necessary,...

 

[Starcraft5834]

Re: 3.0 belts always breaking

What Bondo said... your alternator bolt on the swing arm is probably wiggling loose causing slipping and scrapping,= snap! clean pulley slot, get new lock washer, the belt's probably 42 inches,,,, you can find em at Auto Zone,, I did....... keep a spare handy too

 

[Starcraft5834]

Re: 3.0 belts always breaking

if you see "black powder residue" on the floor of engine compartment below the main pulley, your belt's being sanded off...litterally.. that's what mine was doing...

 

[sweet addiction]

Re: 3.0 belts always breaking

At one time I had the same problem with my 3.0. I put on this belt - http://www.summitracing.com/parts/gtr-15402 and put a helicoil in the alternator so I could actually tighten it properly. It has been running for about 6 years now without breaking a belt.

 

[Starcraft5834]

Re: 3.0 belts always breaking

I bought two like belts.. mine broke late in the season, about 2 miles from the dock (naturally), noticed a "hot smell" as I was full throttle on one of the NYS Finger Lakes, , saw my temp guage over 200.. wow!!! backed it off and limped in at low rpm, temp went down to 160deg...no damage at all...thank goodness.. used it in Sept at 1000 islands, was fine,,,,plan on getting a new lock nut with teeth to keep that baby tight....

 

[grewvin1]

Re: 3.0 belts always breaking

I go with Bondo and the rusty pulley look for rubber dust above and below and any rust on pulley will eat a belt.

 

[fishrdan]

Re: 3.0 belts always breaking

to help keep the altenator tighter to keep the belt tighter.

From that comment I take it that the belt is getting loose... As the others said, rusty pulleys are eating up your belt. Clean the rust off, paint the pulleys, let the paint cure (get hard) and then reinstall the belt.

Check to make sure the bottom alt bolt is tight too.

And, loop a spare belt around the front engine mount while you have the spacer removed and zip-tie the belt out of the way (ready to go for the next time the belt breaks).

 

[loie587]

Re: 3.0 belts always breaking

Thank You guys. We will try it this season.....