Installing Silver Top CA20E A/C into Black Top CA20E

tgposkitt · 03:01:34 AM / 29-Dec-19

I'm considering installing an A/C system from a post 02/86 XE which came with a silver top CA20E with ribbed accessory belts into my '84 black top CA20E with v-belts. I would have to swap out the ribbed pulley and clutch from the compressor for v-belted ones, and a matching tensioner pulley for a v-belted one. Has anyone done this before? And, are there cars that share parts with the '84 A/C compressor system?

JonB · 09:47:08 AM / 29-Dec-19

I have no idea. I think i have the compressor for the ca20 black 1984. And one from a dr30 there too. Not sure i can id which is which.

weitrhino · 12:08:46 PM / 29-Dec-19

The 84 had a different compressor model even though it looks physically identical to the later version. The main difference is the high pressure and low pressure sides are opposites. Youâ€™d need to account for that. Two years ago I rebuilt the system in my 85. It had a dealer installed A/C system - not factory installed - and they used an 84 compressor. You can read more about my process below.

https://club-s12.org/forum/index.php?topic=38453.0

tgposkitt · 12:35:54 PM / 29-Dec-19

I'm actually installing a dealer installed A/C kit for 1986.5-1987 CA20E into my 1984 CA20E without A/C installed. I've been told that it mounts straight up and the only difference is the compressor pulley type.

Is it possible to swap the clutch/pulley assembly from the A5000 v-belted model to the MJS170 ribbed belted?

Quote from: weitrhino on 12:08:46 PM / 29-Dec-19
The 84 had a different compressor model even though it looks physically identical to the later version. The main difference is the high pressure and low pressure sides are opposites.

Did your A5000 require a v-belt?

weitrhino · 08:48:03 AM / 30-Dec-19

I canâ€™t answer if the clutch is swappable because I donâ€™t have both compressors to compare. Iâ€™m also out of state for a while and canâ€™t look to verify but Iâ€™m 99% certain the A5000 runs a V-belt. Make that 99.99%. It should mount exactly the same though.

Get a green O-ring kit compatible with R-134a and convert the valves right off the bat. No sense trying to use the more expensive and increasingly rarer R-12.

Where did you find a dealer A/C kit?

tgposkitt · 01:56:45 PM / 30-Dec-19

I found it on one of the Facebook pages. The seller wants $300, how much do you think it's worth?

weitrhino · 02:29:41 PM / 30-Dec-19

Oh, I think Iâ€™ve seen it but donâ€™t know what all it contains. If you follow the link I posted above it outlines all the parts in the system. If you live in a hot area it may weâ€™ll be worth it for a new compressor and condenser. Of course, youâ€™ll still have to vacuum and charge the system.

SC S12 · 02:42:14 PM / 28-Oct-20

Quote from: weitrhino on 08:48:03 AM / 30-Dec-19
I canâ€™t answer if the clutch is swappable because I donâ€™t have both compressors to compare. Iâ€™m also out of state for a while and canâ€™t look to verify but Iâ€™m 99% certain the A5000 runs a V-belt. Make that 99.99%. It should mount exactly the same though.

Get a green O-ring kit compatible with R-134a and convert the valves right off the bat. No sense trying to use the more expensive and increasingly rarer R-12.

Where did you find a dealer A/C kit?

Quote from: tgposkitt on 12:35:54 PM / 29-Dec-19
I'm actually installing a dealer installed A/C kit for 1986.5-1987 CA20E into my 1984 CA20E without A/C installed. I've been told that it mounts straight up and the only difference is the compressor pulley type.

Is it possible to swap the clutch/pulley assembly from the A5000 v-belted model to the MJS170 ribbed belted?

Did your A5000 require a v-belt?

This may be moot now but :

clutch swap between the old and new compressors just fine, I did not even have to re-shim. you will need a special removal tool thats all of 4 dollars from the parts store... You can try to hammer off the clutch pack, but you risk damaging the shaft or end seals doing so.

Why Do I know this? a Rib belt Compressor is like 70 bucks. A Vbelt compressor is 400, hard to find, and the first TWO v belt compressor rebuilds I ordered leaked oil out the back of the housing not even under pressure or installed.
On a whim ordered a rib belt one from ebay, swapped the clutch, and have been using it since june with no issues. also for me : my Stock black top V belt car and stock silvertop Rib Belt car have the same hi/low pressure sides on the pump, and use all the same hardware.

There is a seller on Ebay with two full AC kit boxes, from the dealers but listed incorrectly for the FWD 200sx of the 90's...he wants something like 800 for each kit though. A bit steep for our crap boxes IMO, but where else are you going to get the ENTIRE kit.

Personally I have found that running 134 in our systems does not produce the "best" results. Even adjusting for the different densities of the gasses, and filling properly by weight FOR a r12 to 134A conversion, you run into a lot more cycling especially if its below about 80F or is raining/high humidity. I filled mine with ester r-12/134a compatible oil, and dye. After 6 months I will evac out the 134 and refill with r-12 if there is no real leakdown.