Check out the forum entitled "Fastlane feedback". It's accessed from the first page. Most folks who order parts from Fastlane get them in two days or less because they use the closest WorldPac warehouse. And, if you get the order up to $100., you don't pay a dime for shipping. Otherwise, you pay actual UPS shipping costs.

So, your excuse to use inferior parts is eliminated.

Thaks for the tip, Brian. I continue to learn more and more all the time.

The outcome...for now
 

I said I would report back, and here it is. I received the belts and changed them out. Thanks to the great tips on this site, with a little patience, it did not prove to be too difficult of a task for me. That's the good news. I do continue to second guess myself as to how much tension to put on them. Any good rule of thumb for this novice?

Within moments after starting the engine, the power steering belt began to abrade slightly on its edges. I can see that the pulley on the power steering pump is not spinning 100% true and attribute that to the cause.

The bigger issue continues to be the A.C, compressor. I no longer have the squeel that started this ordeal, but with the A.C. on there is a noticable, rough sound. Some what irregular, like a few pieces of gravel being slowly shaken in a box. Almost like the sound of a playing card in a childs bicycle spokes, but irregular, as mentioned above. Once the A.C is turned off, the sound becomes much less noticable and the faint growling that is heard has a regular rhythm. Sorry that I am not better at describing the sounds, On the bright side, at no time while letting the car run for the 10 minutes or so did I hear the awful squeel.

I guess I'll wait and see what the compressor or belt throw at me next and try to decide on a course of action based upon that.

Thank you all for your help and suggestions and as a novice I welcome any further insights you may have.

That Harrison compressor is a POS General Motors spec R-4, with MB spec of a 9 o'clock clutch placement so the wire hook up is at 3 o'clock when looking at it from the front. The gravel sound you hear is the compressor getting ready to sieze up. Sometimes they will sieze up for a moment and let the belt snap then release. Other times the lock up hard. You need to turn it again by hand in the direction the pulley spins. Some time you can turn them 3 or four time, then you feel it lock.

I cut my teeth on the POS R-4 working for a Cadillac dealer. I replaced more of those than I care to remember during my summer of high school employment.

Why MB used a POS GM part makes no sense.

Does synthetic oil help?
 

I too am working on my ACC. I determined that the low pressure switch on the dryer is either bad or there is not enough pressure in the system. If I bridge the wires that go to the pressure switch, the compressor clutch engages and the compressor turns freely. AFAIK it still has R12. I recieved a set of guages in the mail today and will check my pressures when I get home.

Now the question: I read the writeup Diesel Giant did on replacing the compressor and using synthetic oil. Does anyone know if this really makes a difference in the long term. Will it really make these POS compressors last longer? Does anyone have real world experience with this?

The sound I had was a horse walking on cobblestones, or perhaps a marble in a clothes dryer.

Belt tension was the problem. I bought a kriket tension gauge at NAPA for $10, found the belts loose, and the noise went away when the belts were tightened properly.

This was on a newly installed reman R-4, with all new Conti drive belts (from Fastlane :D )!

On borrowed time
 

Just got back from picking my son up. boy, was he embarrassed for his friends to hear the sound the car is making.

I have a better description of what the sound has developed to,the sound is back to what I originally heard when this ordeal started: Fingernails down a chalk board. Not constant, but with some regularity. When it's not making that sound, it's the rough gravel sound.

I guess the POS belt from Auto Zone, that I wouldn't have had to wait for and could have had for half the price of the one I bought, would have worked just fine for this application:behead: I guess I'll run it until it seizes up all together and then go from there:mad:

Check the tension. Using the Kriket gauge was a real eye opener. Properly tensioned belts were WAY tighter than I would have guessed by feel.

All noises stopped for me when the tension was correct.

Thank you for the suggestion. I'll pick up the Kricket tool tomorrow, but I don't expect that to be the answer to my problem.:mad:

I'll bet you the "rock tumbler" sound you're hearing is being caused by the compressor belt not having the right amount of tension. They have to be really tight to funcion properly and not make that noise. I went through a major a/c overhaul last month because the clutch on my compressor had seized, a new compressor with the stepped ports, not a remanufactured unit. My belts were old anyway and I was getting that sound. I tightened it up, the noise went away, and the belt promptly snapped a week later. I've got a new belt and a new remanufactured compressor on there and the belt is slipping a little at highway speeds(higher constant rpm) but its fine around town as long as I don't go over 35 mph. I checked the belt tension with my thumb and its stretched into place over the last three or four weeks so it needs tightening. I bet if you tighten yours the noise will go away.

As I said, I will pick up the Kricket guage that has been recommended, but from what I'm reading here, I guess it's best to have the belt too tight and err in that direction as oppossed to not tight enough.

When the time comes, probably sooner than later, for me to get a new compressor, what is the best source and manufacturer you recommend?

Watch out for the offshore stuff
 

Go with a GM or Harrison compressor. I don't know if rebuilt is as good as new or not. In my experience with other rebuilt parts it is a crapshoot. I know putting a compressor in is a major deal for a DIY, so I would tend to go with a new one, and I would stay away from any off brand.

You may also want to search other threads for R4 compressors imploding. I think there is the possibility of sending chards of metal into the system if the compressor self destructs. There has also been much discussion about the amount of oil in the system. If some of the oil has leaked out you don't know how much to put in to make the system right. Too little and it reduces the life of the compressor and I think too much also has detrimental affects. I think the only way to know for sure is to start from scratch by removing the compressor, dumping the oil, refilling with the correct amount, etc. Do a search for Diesel Giants AC compressor replace and flush write up. It is very good with excellent photos. He also uses synthetic oil in his system.

When I did this job last month, I went with a rebuilt unit.

My theory is that most of the bad rap the R-4 gets is due to the higher head pressures encountered with R-134a conversions. Since I stayed with R-12, my head pressures should be within the original design range of the compressor, and lead to longer life.

The second reason (and the deal sealer for me) was that the new compressors come with "stepped ports". This means the suction and discharge ports are on slightly different "planes" at the manifold connection. In order to get a seal, you have to use seal rings, which are metal/rubber combos that raise the sealing surface on the lower port up to be coplanar with the higher port. There have been numerous reports of getting leaky seals at the manifold using these seal rings since our manifold hoses have "non stepped" or coplanar ports. I think all new R-4's come stepped, remans come both ways. I bought the compressor locally, so I opened the box to examine the ports before purchase. When I saw non-stepped, the deal was closed.

The last reason was price. $108 for reman, $220 for new.

No Kricket guage to be found
 

Techguy512,
Thanks for your input. When this compressor completly gives up the ghost, I'll have my mechanic put in the replacement, but I will discuss your thoughts with him.

I went to NAPA, Auto Zone and Advanced Auto looking for the Kricket belt tensioning guage you recommended, all to no avail. No one had even heard of such a thing.

I guess I'll pop the hood and just tignten the belt to the point of having it as taut as possible.

I got mine at Napa. It was a cheaper, plastic version of this one, sold under the part number KR-1:

http://www.midwayautosupply.com/detailedproductdescription.asp?13199