part number for aircon belt?

looking for the correct part number for the aircon on a '98 p38 2.5dse bmw. tryed the drive belt and then was geven a, 4pk855. which i've found out is too loose. douse anyone know???

Aircon belt for 2.5 diesel is STC 3397.

is that landrovers own make?

I fitted a 4PK855 no problems?? on a 2.5 Diesel??

But - I did find out that according to a large retailer of aftermarket parts that they sell anything from 4PK830 to 4PK855 for the 2.5 Diesel

Why not just measure the old one? or the route it takes and ask your local autofactors for the nearest size and make a note of this for next time??

the 855 was just about an inch too big. there were two on the books for the 2.5td( so they tell me) so i'm guessing its got to be the other one...i'm about to go there now and see..your fitted ok you say... thats a bit worrying..hope theres two belts on them books....
thanks for your help

This was covered in another thread the other day;
http://www.landyzone.co.uk/lz/f10/aircon-belt-feel-off-189357.html
I'm surprised the 855 is too long. Try putting the adjuster on the upper tapped hole. In a moment of annalness I checked what is fitted to mine - 4PK836 - and the adjuster still has a fair bit of unused movement left. If you've still got the old one and it's not shredded check the number on it.

Bumping up this older thread with new information. I've been struggling to get the air con to work consistantly across the summer. The belt that was on would drive OK for a while but then start slipping and squealing. I think it was either stretching or settling onto the V ribs as I could tension up further and it would be OK for a while......then start slipping, etc. It got to the point where the tensioner was hard up against the air con pump pulley and the belt wouldn't stay on and continually threw itself.

The belt (of unknown make, the markings on the back had worn off) was either stretching a little or settling onto the V's. I suspect that slipping would make this worse. It hadn't started to crack or break up and looked OK.

Anyway I've come up with an alternative solution. I wanted a shorter belt and browsed Ebay on the belt part numbers. You can get belts in 10mm increments from 4PK820 through to 4PK850 as they're fitted to various cars. I noticed that a 'stretch' 4PK830/4PK850 was advertised for the 335D BMW. Browse on 4PK830. It works a treat. It's a bugger to get on as it's too short to slip easily over the pulley's. You have to get it on the crank pulley and work it round the A/C pulley as far as it'll go across the bottom, quick flick of the starter motor plus sideways pressure by a screwdriver and it jumps on. Just like getting a bike chain back on. BUT MAKE SURE YOU'RE WELL CLEAR, be safe. I had to push it sideways again to get the V's and grooves in the right place. It's tight enough to run like this without a tensioner - take it off before trying to fit the belt. But it doesn't feel so tight to overload the bearings. I ran it this way for a week and it worked fine. It must have settled in a bit as I've got the tensioner on now but in the lowest position.

This 'stretch' belt didn't feel like it had any stretch in it. It was a SKF, a known 'name' manufacturer, who make bearings so I'm hoping it's a good quality one and lasts. Unlike the main serpentine that I've also replaced - taking off the new one I put on in April 10K miles ago. I could see it was cracked but there was a chunk of the rubber missing and down to the canvas in one spot when I got it off - about to shred by the looks of it.

Long tome, but try the stretch belt, it worked for me.