Drive Belts again!!

Okay. I confess. When I refitted the HP pump last week, I also changed the water pup/ alternator drive belts again! I was still finding the '983' belts I'd fitted last August too long so....... I bought a pair of 975s in the autumn. They are 'Gates Delta Narrow SPZ975s' and - at last - they are *just* right. But i've said that before.

I'd already tried several different sizes of belts, but hadn't really been happy with any of them. You can read about that HERE.

It took me ages to set this photo up

On my car, the 975s give adjustment room on the alternator bracing bar.......

.............and don't put the alternator too close the the engine.

Now, although they are clearly marked '975' these aren't the same length as the '10 x 975' belts you can buy. The reference number seems to relate to the 'datum' length. The belts I'm now using are 975s, but have an outside length of 988mm. They are 10 x 988s.

Saga of my drive belt lengths

For a 10 x 975 belt, the 'datum' length (and so part number) is '962'.

'10 x 975' belts are ''962s'..........

For most Ds I believe that 10 x 975 belts sold by the D parts people will be just fine. It's the larger size of the pulley on my alternator that makes them too tight on my car.