GlassicAnnex
Don Updates his Air Conditioning

This page deals with the compressor, see this page for
pics and story of updating the evaporator and in-car parts of the AC.

5/11/04

Here is the saga of my air conditioning update. My 1978 Phaeton had not had working air conditioning for several years. The previous owner's "story" was that the AC was working but when the rebuild engine was installed, it was just not hooked up again. He connected the electric wire to the compressor and showed me how the compressor clutch came on and off on demand. When I finally built my hard top and windows, I was ready to get the AC working.

Well, it was quickly obvious that the car needed a new drier (located under the front bumper). A pressure test showed that it also had a leak at the front seal of the compressor. A local AC shop said they would replace the seal for $90 - but the mechanic said that he really didn't want to do the work, and that most people just buy a new compressor.

The compressor in my car was a Sanden SD 508, which fortunately is a fairly common item that is still made today. They seem to now be called "Sanden" compressors for Sanden/Sankyo (They must have merged later on). They are a also popular in the hot rod business. They can be found in local auto shops for around $200 -- but I was able to find a chrome plated new one for $250. See Rainbow Products info at the end of this article.


There are a few options for the SD 508: whether they are set up for Freon or the R134A refrigerant - also whether they have a double pulley, like mine, or a serpentine belt pulley. The compressors also come in a "polished" finish, priced between plain and chrome. My vendor, listed below, also sent me a chrome plated drier, at a cost of $65 -- plus postage. The drier had a bracket with it, which was backwards for my use, but the bracket was held with a hex head set screw, so I just spun it around.

The issue of whether to convert to 134A refrigerant came up, and I decided to take my chances with the less costly, more environmentally friendly newer system. Discussion of this topic appears here.
Not only was my drier all rusty, but the brackets holding it were also nasty. I made new ones from some 1/4 inch aluminum bar material that I had. It buffed up fairly nicely. The old drier can be seen toward the top of this picture. (I slapped some paint on the rusty soup-can sized drier) but you can still see the rusty bracket and clamp. This picture is looking up from underneath the car. Another view of the old drier with measurements, for use in finding a replacement. The new drier with my home-made arms looks like this:

and a side view:


There were rubber stoppers on the threads when I got it, and the circular clamp part of the bracket came with the drier.

When installing the new compressor, the issue of fittings for the service ports came up. The old fittings can be converted with adaptors, but my new compressor did not have any fill ports at all ON the compressor. So my mechanic was going to splice them into my hoses. I tried to find 90 degree fittings for the compressor with the service ports right in the 90 degree tubing. This proved not so easy to accomplish. The local Advance Auto Products could find nothing in their catalog. A local air conditioning / radiator shop didn't have any in inventory and suggested a hot rod "after market" installer several towns away.

I then called Rainbow Products where I had bought the compressor, and asked them to ship me the fittings 2nd. day UPS. They did and the items were shipped immediately. The fittings were $25.00 plus $11.00 for the two day letter rate UPS.


These fittings turned out to be CRIMP-ON fittings. My local mechanic did not have the crimping machine, so I had to take the car to an AC shop to have them put on. They charged me $20 and did it while I waited. The guy there "warned" me that the hose coming from the dashboard was "an old GM stye hose" with ribs along it, and that they WERE prone to cracking when crimped. Of course, once crimped, the fittings can't be reused. He said that they usually recommended using new hose when installing this type fitting. Since the other end of the hose terminated inside the dash, I said we could take a chance on it holding. He saw no splits when he put the fitting on, but we wouldn't know until the system is pressurized.

There may be other types of fittings designed for slip on with a clamp over the hose. I don't know.


The new compressor was installed, the crimp fittings held, and the system blew cold air! After several days it appears that there are no leaks, and the car stays comfotable in hot weather. My mechanic charged me $120 for the installation which included a new belt since the pulley on the new compressor was smaller than the old one. I had removed the hood and side panels so that the mechanic didn't need to spend time on that.

I noticed that the fan for the air conditioner is noisy, and even the lowest fan speed seems pretty high. There is a definite clicking sound that comes from under the dash when the compressor kicks in and out. The overall conversion and upgrade was a success.

Rainbow Products -- I met Mike Brown at a large hot rod swap meet, and he quoted me $250 for the chrome compressor. He didn't have on at the show, but when I ordered it by phone, he shipped it IMMEDIATELY. The compressor was damaged (probably was dropped even before HE got it) and he very quickly sent me a second one. He didn't ask me to wait until the first one was returned.

The second compressor came very quickly, and, a couple of days later when I ordered the fittings, they also were shipped the day I ordered them. As Mike had said he would, he later refunded my postage to return the first compressor.

The drier that he shipped worked great, and he called it an "old Chrysler drier -- #6 O-ring fittings" Here is the info on Rainbow Products -- I suggest the phone, since I am not sure how often Mike reads his email.

Rainbow Products
Automotive Fans and Air Conditioning
2525 Centenary Church Rd.
Mt. Ulla, NC 28125

www.rainbowproductsonline.com

 click to see more about air conditioner upgrade