FYI for CP27 owners. I purchased a v-belt from Westerbeke, part no. 302084. What I got is a Gates XL belt, Gates No. 7355. There is a sub-number on the belt as well, 10A0900. Westerbeke price was $40 plus shipping. It looks the same belt can be had online if ordered as a Gates belt for about $10-$15.
Yep, I've been ordering mine from Amazon for a while. You can try different lengths (7350, 7355 or 7360) to best suit your alternator's range of adjustability.
I'm not thrilled with the amount of shedding from the Gates belt. I spend way too much time wiping up black dust. Would love to find a low-shed belt.
Wes
Wes - I'm glad you mentioned belt dust. The belt I have to remove has left a lot a dust, so much that I thought my belt was rubbing or misaligned. I saw nothing that was an obvious culprit, so all the dust I have been getting left me puzzled. Thanks for sharing your experience.