Searching through older posts, within this site, they all seemed too old to hold much value. I have a 2000 MKII with a Universal M-35BC with the standard alternator and I have had two belts completely come apart, leading to a high temp alarm. Both were caught early and replaced. These events both happened within 2 years of each other. I don't know how many hours the previous belt had, but the first I replaced lasted less than 30 hours of run time I would guess. I replaced that 2 days ago and have run it on a delivery for about 5.5 hours. Any thoughts? That seems like too many in too short a time. Tension appears good. I'm wondering if it's running too close to a hose clamp for the water hose.
Thanks in advance
On my M35B the belt would rub against the engine and there was black dust everywhere and the engine would vibrate excessively. It was mostly due to cracked alternator hinge which broke eventually.
After replacing it I also had to place a washer at the semicircular alternator bracket bolt on the engine side to keep the belt rubbing against the engine. No more black dust.
Also check the propeller shaft coupling alignment.
Sail La Vie 1999 Catalina 36 MKII, M35B-17031, Coyote Point, San Mateo, CA
About Sail La Vie
Are you using the stock Westerbeke/Universal belts? I had tried others to include a NAPA belt that was supposed to be a direct replacement, but for some reason could never get my tension right and they would slip and ultimately shred. Checking alignment should help. Make sure nothing is rubbing.
Also check the pulleys themselves. Some can get a bit rusty and create extra wear. My crank pulley was rusty as hell from a leaky raw water pump so I needed to wire brush it and clean it up a bit.
Finally, is there a ton of black dust in the engine bay?
Hope this helps!
"Luna"
2003 MKii
Standard Rig, Wing Keel
Hull #2160
Bristol, RI
If you remove the engine compartment cover and run the engine in neutral, can you see the belt contacting any thing? Also try adjusting the throttle speed and see if the belt touches anything then. How do the the pulleys look? Any unusual wear on the inside of the flanges?
Even a well-tensioned belt vibrates to some degree between pulleys. Our belt creates a minor amount of dust, and it generally lasts for at least 3-5 years. (We only do 50-75 hours/year).
We changed to an Oberdorfer pump and the belt comes close to one of the lower nipple, but does not come in contact.
Paul & Wendy Keyser
"First Light"
Rye NH
2005 C36 MKII #2257
Wing, M35B