Alternator Belt Challange

[Dan Stokes]

Just wondering if anyone else has had this issue:

When I got the OM617 (1984, I got the whole car) it had 2 newish alternator/water pump belts. The problem was that they wouldn't QUITE tighten all the way. They were 15-395 - "15" is the belt width series and "395" is the length in inches, 39.5 inches in this case. After a bunch of trips back and forth to the parts store I found out that the right belt, at least on my engine, is a 15-390. Different makers use different numbering methods but the 15 (or whatever series) and the length in inches seems to be pretty standard here in the US. The belts I got are Dayco and actually there is no dash between the width and the length.

Anyhow, they only had one so a second one is on order. The parts store manager seems pretty knowledgeable and he says that the manufacturers no longer package them as a matched set so I'm hoping they are close to the same length when the second one gets here. Double belts seem like a bit of overkill but neither the WP nor the alt have much wrap around them so I'm guessing that's the reason for the twins.

So - any other input on this?

Dan