R12 0r 134A
Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=192692
Printed Date: 04 May 2025 at 12:53pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com
Topic: R12 0r 134A
Posted By: SteveM C/IL
Subject: R12 0r 134A
Date Posted: 01 Jan 2023 at 8:48pm
| My recent purchase (8070) came from Minnesota (I'm told) and has original R12 fittings on A/C lines. The belt is gone,the R4 compressor turns ok by hand with clutch engaged (not locked) and still has some pressure on system so it's not "broke". Most things this age have been converted to 134 and have the corresponding fittings installed. With the right fittings you can do 134 through R12 fittings. Has a reman R4 but who knows how long ago. (NO HISTORY) What's the chances it is still on R12? Is there a way to prove it? I still have some around here somewhere. Trying to decide what approach to take. Since this machine will need to be dependable (A/C must not fail!!) I know I should just replace it all and be done Like I did on my other one but if I can make it work why not? LOL! Time you break it apart and flush for new oil and 134 maybe change it all to AP Air and be done. My problem is I like to see if I can make things work. Yeah, I got a few bite marks back there. |
Replies:
Posted By: DrAllis
Date Posted: 01 Jan 2023 at 8:51pm
| In my opinion, a Delco R-4 compressor isn't worth keeping. Remove it. Place it on the open tailgate of your pickup and hope it falls out somewhere it doesn't do any damage. |
Posted By: steve(ill)
Date Posted: 01 Jan 2023 at 8:56pm
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i doubt the put 134 fitting on to charge it, then took them back off.. Once you convert over, you LEAVE it that way......... If it has 12 fittings, i would bet it is R12 system. ------------- Like them all, but love the "B"s. |
Posted By: SteveM C/IL
Date Posted: 01 Jan 2023 at 9:06pm
| Yeah,I know what I should do..... |
Posted By: im4racin
Date Posted: 01 Jan 2023 at 10:04pm
| I put the 134 fitting on my M2 and topped off the remaining 12 that was in there. It put frost on the windshield at 90 above. What are you out? |
Posted By: SteveM C/IL
Date Posted: 01 Jan 2023 at 11:17pm
| Down side to that is what if it quits in middle of spring season? Too warm in there on a sunny day with no AC. Would have to break out the 220 open station. |
Posted By: im4racin
Date Posted: 02 Jan 2023 at 6:46am
| It will work or not right from the start. If it quits blowing cold just add some more. The chances of a catastrophic failure is pretty slim. It probably has a noisy compressor already and that's why the belt is off. Try it in the shop now and see why the belt is off |
Posted By: DMiller
Date Posted: 02 Jan 2023 at 6:51am
| 134a is not compatible with the oils used in 12 systems, produces a reaction that destroys everything in contact with over time. Entire systems has to be flushed and correct to refrigerant type oil installed. |
Posted By: DaveKamp
Date Posted: 02 Jan 2023 at 2:42pm
The problem now, is that you've got a fixed orfice system (not a TXV) with an incongruent mix of refrigerant at an improper level, where ONE of the two is in a very excessive superheat condition. This is basically inviting your evaporator coil to become a toxic bomb ready to flood your cab with dichlorodiflouromethane and tetrafluroethane. About a half-lungfull of that, in a quarter second, and you're out... and trapped in the cab, to asphyxiate. The biggest investment of servicing an HVAC system, is the time and equipment. If you want it to work well, and be reliable, just strip the old stuff, mount up a new compressor, new condenser, get a new receiver and filter in, flush the evap coil clean, vacuum the exterior of the coil, get new plumbing in, then pull vacuum, charge the system, leak test it, and then cycle it up. Once you have it set up right, it'll serve you well, for a long time. Half-wit it, and it'll be problematic and lame.
------------- Ten Amendments, Ten Commandments, and one Golden Rule solve most every problem. Citrus hand-cleaner with Pumice does the rest. |
im4racin wrote:Posted By: HudCo
Date Posted: 02 Jan 2023 at 6:48pm
| if the belt is off and you are turning it by hand that just means the clutch is not engaged i would bet if you energize the the clutch you cant turn that compressor and if you can it is an hour away from burning off another belt |
Posted By: SteveM C/IL
Date Posted: 02 Jan 2023 at 8:20pm
| With low pressure jumped,the clutch clicks and you can turn it by hand with small effort. Otherwise it just spins freely that's why I say it's not locked up. |
Posted By: ddlong
Date Posted: 02 Jan 2023 at 8:49pm
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does anyone know what is being used after R134a? I do grocery store, convenience store refrigeration and the long term refrigerants(134a, 404a, 410a, 507, 407a & c among others) are slated to be no longer manufactured like 12, 22 & 502. I know one of the 1234 refrigerants is being used in vehicles today, just assumed that’s what is being put in ag machinery. And the 134a oil in mobile AC was/is different than stationary AC/refrigeration, PAG(poly alkaline glycol) for mobile, POE(poly oilester oil) for stationary. Don in IA
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Posted By: Steve in NJ
Date Posted: 02 Jan 2023 at 9:05pm
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I wouldn't even mess with the old R12. You know what to do already. Change the fittings over to R134A, install a new compressor, vacuum down the system, check for leaks, inspect the hoses and charge it. You can probably pickup one of those Sanden A/C compressors pretty reasonable. Take that R12 compressor and use it for a boat anchor...... Steve@B&B ------------- 39'RC, 43'WC, 48'B, 49'G, 50'WF, 65 Big 10, 67'B-110, 75'716H, 2-620's, & a Motorhead wife |
Posted By: DaveKamp
Date Posted: 03 Jan 2023 at 9:45pm
Or if it's a sump-type York, use it as an air compressor for an on-board air tank... put a switch on the dash, which sends power to a pressure switch/unloader on a 5 gal tank, then to the clutch... a guy can always find a use for an air-hose... ------------- Ten Amendments, Ten Commandments, and one Golden Rule solve most every problem. Citrus hand-cleaner with Pumice does the rest. |
Posted By: DMiller
Date Posted: 04 Jan 2023 at 9:37am
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HVAC guy I deal with stated are using a Propane base refrigerant now Not sure I could trust a flammable gas type even as state is not hazardously flammable. |
Posted By: ddlong
Date Posted: 06 Jan 2023 at 8:05am
|
propane & isobutane are being used in residential and has been for awhile. One commercial manufacturer has been using propane as a refrigerant for close to 10 years. There are only 3 refrigerants approved for permanent use going forward: Propane/Isobutane, CO2 and Ammonia in stationary equipment. Everything else is bad in some way shape or form according to the “climate change” specialists. That is why I asked the question of what is happening in Mobil air conditioning going forward. Going from R12 to R134a seems to be only temporary as R134a is on the chopping block too. Don in IA |