V Belt Change Instructions

[617collector]

Hello All,
Does anyone know of a good shop manual or website showing the steps on how to change the power steering, alternator and AC compressor belts? The more pictures the better! 1985 300D. Thanks!

[vstech]

it's a pain.
remember this. all devices have 3 bolts and one adjuster!
alternator and a/c compressor use 19mm bolts on the back side of the device.
p/s uses 13mm bolts with nuts you have to hold on the front side.
use penetrating oil on the adjuster for the alt first!!!

[4thesporty]

John makes a good point that all three have THREE bolts plus the adjuster bolt. If you can't find the third, keep looking for it.

If the front of your engine, especially the PS area is grimy it would help to clean with simple green and water hose first for better visibility.

Edit: Also, I don't think any of the bolts need to come out, they just need to be loose to adjust the component.

[andrewjtx]

Make sure to have an assortment of wrenches, extensions and u-joints in the sizes referenced.

What I hate is that the two that are the most important to keep in good shape (alt/water pump) are the farthest back on the crank pulley.

Also, once you get them changed, you'll most likely need to re-tension after they've been run a bit. Hopefully not much.

[toomany MBZ]

There's a pic from the FSM in this Belts Question link.

[mach0415]

When replacing the belts, make sure the length you get from the parts house is correct - before installation -
I did things a little out of order by putting all the belts on first and adjusted tension starting with the easiest one first (P/S) and ending with the Alt. belt when I found out the Alt belt O'*****'s gave me was too long - it was for a 300D, not an SD. So off I went to take it back and totally redo what I already did. We do it nice 'cause we do it twice!

[Beastie]

I have a few pics that I can try to send to you later today. But I think it has all
been said above ( TOOMANY MBZ helped me with some pointers)
It really is not that bad but again I say that after I completed it.
DEGREASE, get a light and confirm which ones. I also used the black chassis book that came with the owners manual that way you can also determine which
P/S pump etc and it shows which bolts.
Engine # I ordered the wrong size belt because I ignored that glaringly large
indicator that there is a diff. belt for a later engine.
As stated by others you do not need and do not want to remove these accessories if you can avoid it just because it is a pain getting the bolts to line
up again ( a lift helps)
DO NOT BUY FROM YOUR NEIGHBORHOOD PARTS STORE (BELTS) they will sell you a belt that "FITS ALL FOR THAT YEAR" BALONEY. Get the right size so you get the full life out of the belt and can install without damaging it.
Anyway if you want me to send the pics I have email me.
It is not a bad job by any means.
Alan

[mach0415]

I concur with Alan. It really is not a bad job and everything is fairly accessible one you know where all the bolts are. My biggest problem was not using common sense and being hasty. my mechanic's brain was not working the day I did mine.

[vstech]

edit...
the alternator uses 17mm bolts... not 19 I just got through changing 3 of them.

[Yak]

Originally Posted by 617collector

Hello All,
Does anyone know of a good shop manual or website showing the steps on how to change the power steering, alternator and AC compressor belts? The more pictures the better! 1985 300D. Thanks!

Do some searches on the individual components. I know there are some pics about the layout of the PS pump bolts and Compressor bolts and the alternator bracket.

Make SURE you understand the alternator tension bolt. There's a reason they're all missing from the PNP brackets.

Buy two alternator belts at the same time from the same place. That'll increase the odds they tighten up easily.

I had/have a problem with my compressor and getting full travel to loosen it based on the oil cooler lines, so keep things like that in mind when you can't figure out why the correct size belt won't fit.