1991, 740, non-turbo, Regina Ign System
190k


We have a Denso alternator on our 91, 740. The alt drivebelt spec is always 11.9 X 1000 mm size. That belt is too long for our Denso Alt. For example, I just replaced all three belts new, and on the re-tensioning of the belts (after the new belts "set" in), the adjustment screw on the Alt is already at the maximum position, and cannot be adjusted any further. I took some pics. I'm not sure how to upload them though ( never tried it before ).

This belt issue has been ongoing. But I also learned that Volvo did not use the Denso Alts until 1992 model years, so if that is correct info, then why does our 91 have a Denso on it?

Either one of two things are the answer. 1: This Denso-Volvo Alternator #1398327, was superseded nine times, and Volvo forgot to give the belt size number for this alternator, and kept using the Bosch Alt number; or 2: the vehicle came with a Bosch Alt. and someone changed it to the Denso, As you know, when you buy an Alt you dont get a pulley, so, I suppose the Bosch pulley would not fit and the person either put on the wrong Denso pulley or any f _____ pulley they had available ( I dont know that yet, that is part of what I am trying to find out, and am waiting for info from Denso ).
Another fact, this car was sold used at 50k, at a different Volvo dealership (Keystone Volvo) than from where it was purchased new (Burdumy Motors) - not sure if that indicates anything. We have had our share of problems with it too (perhaps it was a lemon?!).

Of course, the easy answer is to just get a shorter belt, but I am curious as to what the answer is about why this situation is the way it is. I thought perhaps another Volvo owner might be experiencing the same problem, or better yet, no one else is, and that would also explain what most likely happened, which I mentioned above.

Btw, the other drive belts are fine - no issues.

Thank you all,
Diyer