A/C compressor

[cyclemike]

Does anyone have experience installing the Sanden a/c compressor kit? I've been telling myself I was going to replace my broken compressor and switch my system over to 134a for some time. Well, this weekend I began the process. I put the new compressor on(after getting it lined up and shimmed correctly) and I seem to be stuck, somewhat. I need some help with the hoses that go from the compressor to the condenser and evaporator. The fittings don't match up. If anyone has done this procedure before your input would be greatly appreciated. Please let me know, I want to finish this job before the summer is over and I don't need a/c. Thanks.

[Walker944]

Mike,

I did the Sanden 134a conversion earlier this summer. What is it that your having trouble with? I'll try to help.

--Mike

[cyclemike]

Here's the problem, the barrier hose that came with it doesn't fit on one side of the compressor. Please explain how you connected the hoses to the compressor and the condenser. I also don't know how to figure out when my system is fully charged. If you need more info. please let me know. Thanks.

[Walker944]

I’m still a little vague on your specific problem, so let me dialog what I did and see if any of it helps, or if it provides a point of reference for additional conversation. I did this on my early ’85 944.

I got my new 134a compressor ‘kit’ from Vertex Automotive. In addition to the compressor, the kit came with two male compressor fittings, a new length of hose (about 14-18"), hose fittings, hose clamps, 0-rings, and the shims (washers) you referred to. Oh…and NO instructions.

Let me explain what I did for each component:

Compressor: I had to grind one of the unused ‘ears’ to allow proper A/C belt tensioning. Also, I had to install the two male fittings.

Hose from Evaporator to Compressor: Since the new fittlings for the Sanden were different than the Nippondeso, I had to cut the hose just above the compressor fitting and insert the new hose fitting, then clamp it. (Later, due to leaks, I paid an A/C shop to properly crimp the hose.)

Hose from Compressor to Condenser: Removed and discarded the old hose. Discarded the hose clamps that came in the kit. Gave my local NAPA auto part about $8 to crimp both ends. I was careful to note the proper orientation of connectors on either end of hose prior to going to NAPA. If I recall, there is about a 90 degree difference in how the two ends are situated in the hose.

At this point everything was fairly easy to connect together. It took a little effort, but was not insurmountable.

Okay, did this help? If not, where are we still off?

--Mike

[cyclemike]

Bingo, that's exactly what I was looking for. I'm going to grind that mounting tab off tomorrow, I thought about doing it today but wanted to wait to see what others had to say. Yeah, mine didn't come with instructions either however, I consider myself a fairly mechanically inclined person and was looking for a good challenge. If I get stuck, I have learned that it's better to stop and ask questions than force things.(I learned this the hard way)
Thanks man, you've been a wealth of knowledge. When you charged your system, how did you know when it was full?

[Walker944]

The sticker inside the engine compartment says 2 lbs of refrigerant. So I put in two cans. I also have a buddy with access to a vacuum pump and guages, so he pullled a vacuum the system and filled the two cans. He also confirmed that the guage readings were correect for a fully charged system. I'm not sure what the readings should be.

p.s. If you haven't already done so, you may want to consider replacing the expansion valve and receiver-drier. I picked up both (new) locally for far less than what Vertex wanted. I believe the receiver drier locally was about $13 and the expansion valve about $20. Neither is too difficult of a task to replace. It was recommended to me to replace both with the conversion.

--Mike

[cyclemike]

Where is the expansion valve located?

[Walker944]

I must have been a little tired when I wrote the long explanation yesterday...the car I did the work on is my '86 951. On that car the expansion valve is located under the cowling (the black plastic covering at the back of the engine by the firewall) and under the blower.

To get to it and replace the expansion valve here's what you do:

1) Remove the windshield wiper arm that bolts on in the middle of the windshield area. Also, remove the large nut, metal washer and rubber spacer under the wiper arm.

2) Remove the rubber protective strip that runs the width of the engine, towards the back.

3) Gently lift the plastic cowling, taking care not to crack it. The front just fits on the same ridge as the rubber strip you just removed; but, the rear is held in place by two-sided foam tape.

4) Once the plastic cowling is removed you are now looking at the top of the blower. The blower is held in place by six (6) screws (8mm). Remove each of them.

5) Now gently lift the blower out very carefully. It’s a little tricky, but can be some with some maneuvering. Be very careful as you lift the blower in that there are vacuum hoses attached to it from underneath. The blower can be carefully laid toward the engine area.

6) As you look down into the area where the blower was just removed, you should see some black tar tape over on the left-hand side. The tar tape is wrapped around the expansion valve. I just used a utility knife to carefully cut away the tape. Removing and replacing the valve is very straight forward once you see it. NOTE: There is a temperature lead that is clamped into place. Be careful to note the location and manner in which it is clamped for re-installation.

7) Get about 2’ of the black tar tape from an automotive parts house and tape up the new expansion valve.

The whole process only took me about 2 hours.

Just going from memory...hope I didn't forget anything.

[pst]

I did the conversion on my '84 944. I didn't buy a kit because I think they are overpriced. You can buy the Sanden compressor from any street rod parts supplier for $200. I used brackets from a '77 924 (the factory A/C uses a Sankyo compressor--it's called Sanden now), made the shims and mounted the compressor. Yes, you do need to remove the ear. I ordered my compressor with the correct fittings. This way the hoses fit without changes.
The correct charge for R134A is 85% of the R12 charge. So for a 2# system you would use 1.7# or 27.5 oz.