940 alternator belt issues

[vickyg]

Hi all, the troublesome 940 again...

When I bought this car it was fitted with 10 x 925 on the alt belt. This was shedding teeth! On replacing I understood the correct size to be 11.9 x 888. Mechanic who fitted it said it was far too tight and to revert to 10 x 925 at earliest chance which I duly did. Belt slipped and squealed, it was never happy. All Volvo sources I've consulted with insist it's 11.9 x 888. The wider width is fine but but can I fit the shorter belt? I cannot. Slackened off as far as poss, I know how the threaded bolt works, locking etc.

11.9 x 925 doesn't seem to exist.

I could use considerable force perhaps to pry on the 888 but was warned before of damaging alt bearings. Interested in what others have found with their 900s. Car has no aircon.

[Laird Scooby]

Originally Posted by vickyg

Hi all, the troublesome 940 again...

When I bought this car it was fitted with 10 x 925 on the alt belt. This was shedding teeth! On replacing I understood the correct size to be 11.9 x 888. Mechanic who fitted it said it was far too tight and to revert to 10 x 925 at earliest chance which I duly did. Belt slipped and squealed, it was never happy. All Volvo sources I've consulted with insist it's 11.9 x 888. The wider width is fine but but can I fit the shorter belt? I cannot. Slackened off as far as poss, I know how the threaded bolt works, locking etc.

11.9 x 925 doesn't seem to exist.

I could use considerable force perhaps to pry on the 888 but was warned before of damaging alt bearings. Interested in what others have found with their 900s. Car has no aircon.

https://www.ebay.co.uk/itm/324399341778

https://www.ebay.co.uk/itm/303889726063

First is from Lithuania, second from London. They definitely exist!

If you have a local bearing supplier you can probably get an 11.9 x 925 belt which is what Volvo use as it sits "on" rather than "in" the pulleys to improve contact area, even when worn.
In fact, if your local bearing supplier is helpful, they may let you take the car there, remove the belt and push the alternator all the way in on the adjuster and then find the right belt for it.

Alternatively, phone your local Volvo dealer or FRF in Swansea.

[Ian21401]

I just order both my auxiliary belts from my main dealer when I order a cambelt and change them when doing the cambelt as they have to be removed to change the cambelt. Haven’t had any problems so far and the OE belts have the part number and dimensions printed on them.

[vickyg]

What I have is a genuine Volvo belt from a main dealer. They insist as do most part catalogues that it's 888 in length. It's so tight you can't even use the long threaded adjuster, I've have to remove it. Doesn't make sense. Everyone is telling me 925 is wrong but 888 would seem very wrong. I think this car is an odd model, so many anomalies, this isn't the first.

[vickyg]

It is all the way on the adjuster, I ended up removing it altogether to force the 888 on. 925 is I would say too long, took a heck of alot of winding to get it tight and only just.

[Laird Scooby]

I'd suggest going for something like a 900 length then.

I had a few strange things with the 740s i had, all GLE models so same spec and engine but one of them had different length drive belts for no apparent reason.

Like i often say, Volvo seemed to fit whatever they had to hand or on the result of a sacrificial trolls entrails. Sometimes you just have to go with that mind-set and find what fits and does the job.

[vickyg]

Gates has a 11.3 x 912 which maybe will be a compromise, again not found in the UK yet! But what I do not understand is how this car doesn't properly fit any original length. Something must have been changed or a different bracket used yet it's the original alternator.

[Laird Scooby]

Originally Posted by vickyg

Gates has a 11.3 x 912 which maybe will be a compromise, again not found in the UK yet! But what I do not understand is how this car doesn't properly fit any original length. Something must have been changed or a different bracket used yet it's the original alternator.

https://www.heritagepartscentre.com/...c-engines.html

In Shoreham near Brighton so just along the coast from you - well quite a way along the coast really but in the UK.

Are you sure nobody has changed the alternator? What's the Bosch part number on the green label starting "0 120"?

[vickyg]

Yes checked alt with main dealer as well, original and correct 80A . It also has 93 stamped on it so it's done well. MOT on Friday.....

[bob12]

Ah, belts! I use Gates 6375MC belts on the 745 (B200 etc F) without ABS/AC on the Alternator,PS pump,fan. The current ones are about 7 years old with no signs of wear.

They are 11.9 width x 1010mm. The length is just fine assuming you have the original Volvo long screw adjusters on the alternator and PS pump. They will adjust with correct tension at about midway on the adjuster which being Volvo provides mm+++ of adjustment!!

You won't be disappointed!

https://www.gatesautocat.com/p/v-belt/gates/6375mc.html

Bob