compressor back plates?

[Domenic T.]

OK,
My 1st post didn't work well and thanks to Don Hooper I can try again.
The question/opinion brought up by Dale Carlson from another post was (if I remember right) the date code offset to the right under the outlet port (1st pic), is that a decade code? By placing it under the right port? H 14 5, 8/14/1965, could that be 8/14/1975? Hope that was it Dale!

Well all the early 70's Chevy A-6 compressors I saw had a (clutch cut out switch) added under both ports, (inlet & outlet), a switch that only worked if the compressor was in danger of over heat.
As seen below in the 2nd pic (A 6 9) 1/6/1969, the date code is off to the left and not centered as most I've seen.
The 3rd pic is also a 1965 as the 1st pic and it is centered between the ports.
My thoughts is that each day the date code was put on the casting free hand and some got it in the center and some didn't?
I know that the factory had codes (color thread) in their gaskets as to keep mechanics honest when the factory rep approved of warranty work. Lifters also had a ring ground at different places on the case to denote a year.
My question is " the offset to the right, date code or decade code?

Could the 1st pic be from another car manufacturer not using the (clutch cut out switch)? Could it be a 1975 instead of a 1965?

DOM




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[Monte M.]

Re: compressor back plates?

Dom,

I am no expert by any means. I have done a lot of work on auto A/C though.

It might help if you gave a little basic information.
What year car are you working on? Does the car you are working on have, or supposed to have what you are calling "the clutch cut off switch"? (a pin sticking out just below the ports that a wire attaches to)

I have found that very few people even know some compressors have the pin. Plus, that pin sure makes a compressor expensive.

The first and third end caps on the compressor have the same casting number as well. With a close casting date the assumption would be they are the same year compressor.

[Domenic T.]

Re: compressor back plates?

Monte,
I lost a little info in this post when I re-did it from the old post that was chooped at my request.
These pics are compressors I have in stock as I buy them for parts. So where they came from is a guess.
Some have a back ground and they are usually from a collector that has had the car since new or with a good history.
I have a back plate that had the cut out switch added to it, probably during the 1st days of the switch so it could be a exchange unit.
I can tell if C2 are real by the pistons, and all those had the date code under both ports, not all exactly centered but colse.
Here is a pic of a C2 dished piston durring assembly. You can see the dish. The others are flat top with smaller pulleys.

DOM


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