Compressor not holding vacuum

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Cusser
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Re: Compressor not holding vacuum

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Even though this site's software won't "remember me", I do remember that my 1984 V6 Jeep Cherokee had a Sanden compressor.

When it seized in the early 1990s, and compressors were for this were like $700 and unavailable at that time, someone offered to swap the rear plate to a new/different Sanden, still expensive.

Well, I had two little kids to feed, I bought a used compressor from a Jeep wrecking yard for $75, and that worked fine.
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Re: Compressor not holding vacuum

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I had no idea that a Sanden would have isolation valves like a York. Those were the good old days.
On residential equipment the condensing unit used to come with built in hi and low pressure cutoffs, those are gone too
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Re: Compressor not holding vacuum

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tbirdtbird wrote: Thu Jun 03, 2021 7:40 am I had no idea that a Sanden would have isolation valves like a York. Those were the good old days.
I liked the manual isolation valves; I installed that used compressor and only lost a tad of R-12. I used a 1/4-inch socket upside down, using a L-shaped allen wrench to turn the socket on the 1/4-ich square isolation valve stem. There were aluminum dust caps to protect the valve stems, but the caps did not have any sealing function.

Maybe something like this
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Re: Compressor not holding vacuum

Post by Tim »

Yep, if a compressor had tube-o connections. You may see them used. Not just a York item.
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tbirdtbird
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Re: Compressor not holding vacuum

Post by tbirdtbird »

yep, that is it. There is a "refrigeration wrench" with 4 ratcheting sizes with square holes for various sizes of stems.
Also works slick for using small size taps which always have a square shank

I worked on a '61 RollsRoyce once that had isolation valves on the York
61p-TB9lbwL._AC_SL1500_.jpg
61p-TB9lbwL._AC_SL1500_.jpg (41.59 KiB) Viewed 5042 times
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fhorta
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Re: Compressor not holding vacuum

Post by fhorta »

Put freon in and seems to be all good. Thanks soo much. Now it Looks like i have a bit more troubleshooting. Ac only blows through defrost vents. Ideas? (:
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Re: Compressor not holding vacuum

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fhorta wrote: Tue Jun 08, 2021 10:13 pmNow it Looks like i have a bit more troubleshooting. Ac only blows through defrost vents. Ideas? (:
My 1984 Jeep Cherokee had similar issue. Mine had three vacuum-operated actuators to direct its air flows. Two of these were identical part except for a paint color code, as different functions, and the third was different from these. I was poorer then, bought replacement actuators at the parts yard, took my hand-held vacuum pump with me to test before buying.

NOTE: some term these "motors" even though they had no motor !
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Re: Compressor not holding vacuum

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check vacuum lines, start at engine and trace rearward
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fhorta
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Re: Compressor not holding vacuum

Post by fhorta »

Ok. Thanks.

​​​​​​​I have put 2 cans of freon. Cans say they have a net weight of 12 ounces. Compressor originally takes 2.38 lbs of R12. According to a chart, that is equivalent to 2 lbs of R134A. I am coming up with 36 ounces of R 134A of freon to charge compressor. So I would need another can.  Is that about right? When I weighed full can, I got .75lbs
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Re: Compressor not holding vacuum

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Please recall that you will not get all 12 oz out of the cans.
A pound is 16 oz
So 2.38 lbs is 38.08 oz, take 80% of that to get your 134 charge = 30.4 oz

Since you put in 24, I would add another 6 oz
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