82 300D How difficult to change a/c clutch?
 

My A/C pulley bearing decided to do the grind...so I had to cut the belt at work.

My question is, how hard is itto pull the clutch and pulley while the compressor is on the car? Will the puller fit in the limited space?

I can't complain too much since it did make it through four summers here in TX.

Thanks guys!!!

I suppose you are going to do this on the W123? I have done this on my 300SD but could not becasue of space on the SDL. This is something I used as a reference (JAG) but it was helpfull
http://www.bernardembden.com/xjs/comclutch/index.htm

I think Sixto did this. Contact him.

I wish MB used the A-6 instead of the R-4...

From all I've read, pulling the R4 clutch is not a job you want to do in situ on a W123. You need room for the puller and to get the puller threaded in, the R4 cannot have any rust on the shaft bolt. Good luck with that! I had my R4 on the bench and it was a very difficult job to pull the clutch because of rust.

Here is another pictorial. I'm afraid your not going to have room to do the job. But you might if you remove the oil cooler and radiator.


http://www.xmanproject.com/tutorials/r4/r4_repair.php




.

I was thinking about just raising up the radiator and oil cooler to get stuff to fit. I do not want to remove the compressor, and the system works fine, and I do not want to spend more money on a new drier, oil and freon. I would if the compressor itself was toast, but it's not.

Rust is a PITA on any pressed fitting, and being that the compressor gets splashed on from nasty puddles full of crud, I hope there is no rust.

Wishful thinking! It'll be a miracle if you find no rust. Gonna be a miserable job unless you have a lift and can get things out of the way so you can see what you are doing.

At least I do live in a rural are, so no road salt. A lift? That's funny!:D The only lift I have is a floor jack and jack stands...

I did this on a 1982 300D (turbo) earlier this year. No lift, stands, or ramps, compressor in place. If'n I had it to do over again I'd leave the lines connected but drop the compressor.

What tools did you use? And what was the step by step procedure? Same as the others?

Thanks man!

When I do this, I'll take pictures and post them.

Remove center fastener (12 or 13mm), make puller (handy to have a lathe), remove clutch, swap bearing, install clutch, wash hands for three hours.

That has been wished about a million times....

The Factory Shop manual from MB on Air Conditioning... has step by step procedures..
and the special tools described to do it right...
I believe the distance on at least one item is critical... and very small....

O'Reilly's has the correct loaner tools, Autozone does not -- or you may need some from both places. Numerous threads on it from last summer. Funola's probably has the most info:

http://www.peachparts.com/shopforum/showthread.php?t=280510&highlight=compressor&page=2

Now that it's wet and cold...sleet, snow and some rain, this repair will have to wait, as I have a car port, not a garage to work in...:(

But, I am glad to see that the repair can be done with the compressor on the car...

Thanks guys!!!

I do have the FSM on CD...The forum is the best place to ask though.

Ok, I FINALLY did this job. (4th of July Weekend) The way I did it was a total PITA!!!! I'm going to invest in one of those mechanics mirrors!!! It would not have been so bad if I had known these two things...


1. The center bolt was missing from the compressor shaft. I had to remove the compressor with the lines still attached...nasty job. I did mount the compressor in it place, so re-assembly was "in situ", and was not a bad job at all.

2. The idler bearing was SPECIAL ORDER only from the chain parts houses. It was a PITA to pound out of the clutch hub.


Parts bought:

Replacement compressor shaft nut. It is not metric, 3/8" x 24 thread pitch. 9/16 socket fit better than the 14 mm socket.

New compressor V belt

BCA bearing from Greenville Bearing Supply (The original bearing was an SKF BA2-6508.)


What I did...Started in July 2nd. Finished on the evening of July 5.

1. Round up the needed tools: 19 mm gear wrench, 10 mm combo wrench, 13 mm socket and 13 mm gear wrench (For the power steering pump belt removal), clutch plate puller borrowed from O'Reilly and Clutch hub puller from AutoZone.

2. Spent about an hour tring to remove a non existant compressor shaft nut.

3. Spent another hour finally removing the compressor from it's mounting bracket to find the bolt was missing. Removing the tranny fluid line and moving fan shroud gave some extra room.

4. Attached clutch plate puller and removed the clutch plate. The key stayed on the shaft.

5. Removed the clutch hub snap ring.

6. Attached Auto Zone Hub puller and pulled off the hub.

7. Spent 15 minutes trying to pound out the pulley bearing. Found out the bearing must be pounded out from the back of the pulley, not the front. There is a lip that limits how far the bearing can be pressed in, from the front.

8. Spent another 45 minutes pounding out the bearing from the back.

9. Spent a few hours washing hands and trying to track down a replacement bearing. (Websites showed bearing in stock...stores said special order after I drove to them) Bearing supply house was already closed and would not reopen until July 5. It was a 4-7 day wait for the parts houses to get the order in.

10. Spent 2 hours remounting the compressor.

11. Washed hands for 3 hours.

12. July 5...purchased replacement bearing for $37.50 at the bearing supply house...it was a few dollars more that AutoZoo, but was BCA branded, not POS Murray Air.

13. Got home and then...pounded in the new bearing. Much quicker since the shop where I work made me a tool the fit the bearing nicely.

14. Installed the hub. (Tapped lightly with a hammer, using 1/4 in plywood as a pad.)

15. Installed snap ring.

16. Using the clutch plate installer, installed the clutch plate, and left a .25 inch gap between clutch plate and hub. Test spun pulley to check for any drag. All was good.

17. Removed power steering belt.

18. Installed compressor belt and adjusted.

19. Reconnected tranny fluid line.

20. Reinstalled and adjusted PS belt.

21. Washed hands again...

22. Tested, and now have nice cold air again...


So, this job CAN be done on a w123 with out remiving the compressor...

Very cool :cool:

My R4 did the same thing and I came pretty close to replacing the bearing.

Funny, the center nut on mine was missing as well. It looked like it had been off for a long time because the threads had rust on them. I wonder if the nut should be checked periodically?


Good (greasy) job :D

I wonder if it should have had antiseize compound on it...

1980SD...Thanks man!!! The threads were not really bad on my compressor, and I have no idea when it went AWOL. This is summer number 5 for this compressor. I used a nylock type nut as a replacement. I am still using the Freeze-12 without problems so far. I did hear that 134a is being phased out. I bought a can of Freeze-12 yesterday, and it was double of what is was last year.

Leather...I did put some anti sieze on the hub bearing only during re-assembly. Made the hub go on the compressor's "snout" go on much easier.

Good news is there was no a/c oil residue in the front shaft seal area. Also the repair cost for parts was around $50.

Yep, my threads were OK as well, just some kind of heavy surface rust.

They must just spin off :eek: I think you'll be OK with the nylock on there.

I went as far as renting the tool to pull clutch but I found the aluminum "snout" was all galled up and the bearing was loose on it :rolleyes:

Mine was cooling pretty well with 134a before the compressor went out.

Kudos to doing this on the car! I'll bet you could do it in half the time now :eek::D

All because of a nut...

Yep, all because ao a nut...Ain't that the way is always goes?...

I saw a remanned compressor that had a nylock on it, so that is how I got my idea...

I just wish Sanden made a simple, non modifying the lines and pulley drop in replacement!! I would have spent the extra cash to do that.

Half the time would be great!!!! Half the heat would better!!!!

Different sources, to include one of the Harrison compressor maintenance manuals, do not include a center nut in the assembly. They might not go missing, they simply may have never been there in the first place.

http://www.google.com/url?sa=t&source=web&cd=7&ved=0CEMQFjAG&url=http%3A%2F%2Fwww.twistedandes.com%2Fforo%2Fattachment.php %3Fattachmentid%3D64175%26d%3D1248701503&rct=j&q=Harrison%20HR100T&ei=KUsWTuGcJMXm0QHX_8E1&usg=AFQjC NFGZEwcazShVQ8F76yJq2onGTPixA

So we can't blame it on the nuts?

Makes sense, it's pretty stupid, but it is a GM product. I did notice that the clutch disk was pretty far away from the hub before I pulled the disk. I could see where the botl was supposed to go based on the color of the light rust. The place where the bolt was missing was more orange than brown, while the exposed threads were brown.

I have never seen anything that is pressed on, that did not have a backup like a bolt or sleeve just to keep the pressed part from moving.