Compressor not holding vacuum

Friendly format provided to inquire about automotive a/c systems.
Archived Forum

Moderators: bohica2xo, JohnHere, Dougflas, Tim

User avatar
Cusser
Posts: 630
Read the full article
Joined: Sun Apr 24, 2016 6:29 am

Re: Compressor not holding vacuum

Post by Cusser »

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.
tbirdtbird
Posts: 287
Joined: Sat May 02, 2020 1:48 pm

Re: Compressor not holding vacuum

Post by tbirdtbird »

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
User avatar
Cusser
Posts: 630
Joined: Sun Apr 24, 2016 6:29 am

Re: Compressor not holding vacuum

Post by Cusser »

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
Image
User avatar
Tim
Site Admin
Posts: 719
Joined: Tue Apr 12, 2016 2:19 pm
Location: Scottsdale, Arizona
Contact:

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.
------------------------------
Please support ACKITS.com for your Auto A/C Parts and Tool needs.

Help Support the Forum
tbirdtbird
Posts: 287
Joined: Sat May 02, 2020 1:48 pm

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 390 times
fhorta
Posts: 11
Joined: Fri May 28, 2021 7:38 am

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? (:
User avatar
Cusser
Posts: 630
Joined: Sun Apr 24, 2016 6:29 am

Re: Compressor not holding vacuum

Post by Cusser »

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 !
tbirdtbird
Posts: 287
Joined: Sat May 02, 2020 1:48 pm

Re: Compressor not holding vacuum

Post by tbirdtbird »

check vacuum lines, start at engine and trace rearward
fhorta
Posts: 11
Joined: Fri May 28, 2021 7:38 am

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
tbirdtbird
Posts: 287
Joined: Sat May 02, 2020 1:48 pm

Re: Compressor not holding vacuum

Post by tbirdtbird »

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
Post Reply