swap without A/C discharge?
Post Fiend
Joined: Nov 2002
Posts: 9,987
Likes: 7
From: Memphis, TN
swap without A/C discharge?
Yes, if the new engine mounts the compressor in the same location and in the same way as the old, or if you don't plan on using the compressor & just want to tie it out of the way (but then who cares if it discharges).
If you're going from a stock carbed engine to a newer EFI, you'll have to change compressors anyway, so do an R-134a conversion at the same time. If you want to wait, install the EFI's A/C compressor with both ports sealed and the clutch disconnected until you're ready to do the R-134a conversion.
If you're going from a stock carbed engine to a newer EFI, you'll have to change compressors anyway, so do an R-134a conversion at the same time. If you want to wait, install the EFI's A/C compressor with both ports sealed and the clutch disconnected until you're ready to do the R-134a conversion.
Posting Guru
Joined: Sep 2002
Posts: 2,195
Likes: 1
From: San Antonio, Texas
swap without A/C discharge?
I don't know about the difference on the compressors, but I can let you in on a little secret in freon. If you change compressors you don't have to spend lots of bucks on changing over to 134a, you can put r12 or 134a in the same system, they mix like they were made for each other. The hole conversion thing is what the chemical companies tell distributers so they can sell more crap and scare you into keeping them seperate. My dad has been working on air conditioners for over 30 years, and I work with him on my spare time from my real job. hope this helps you any.
82 Bronco 302cu Lariat
83 Bronco 351w (wrecked) parting out, need the money.
Milk sucks!
Got Beer?
82 Bronco 302cu Lariat
83 Bronco 351w (wrecked) parting out, need the money.
Milk sucks!
Got Beer?
Post Fiend
Joined: Nov 2002
Posts: 9,987
Likes: 7
From: Memphis, TN
swap without A/C discharge?
R-134a causes mineral oil (which is used with R-12) to gel & block the filter on the orifice tube.
Also, on a truck that old, the O-rings (all over the system) & dessicant (in the accumulator) are NOT compatible with R-134a and its oil (PolyAlkaline Glycol - PAG).
Also, R-134a carries less heat by weight than R-12, so you either have to increase the size of the compressor (not practical) or increase the head pressure by decreasing the size of the orifice tube (buy the red one instead of the blue one).
Also, the two refrigerants have different dew points, so they'll interfere with each other in the evaporator making it less efficient and can even cause severe damage to the compressor by allowing liquid to enter it.
So it's not just a marketing ploy, and even if it were, it's a poor one because the swap doesn't even cost $100 if you do it yourself. I know this because I recently got my refrigerant license & I had already done a few conversions including my onw truck.
I'll soon be scanning the MACS test book that contains all that info and putting it up on http://www.broncodata.com .
Also, on a truck that old, the O-rings (all over the system) & dessicant (in the accumulator) are NOT compatible with R-134a and its oil (PolyAlkaline Glycol - PAG).
Also, R-134a carries less heat by weight than R-12, so you either have to increase the size of the compressor (not practical) or increase the head pressure by decreasing the size of the orifice tube (buy the red one instead of the blue one).
Also, the two refrigerants have different dew points, so they'll interfere with each other in the evaporator making it less efficient and can even cause severe damage to the compressor by allowing liquid to enter it.
So it's not just a marketing ploy, and even if it were, it's a poor one because the swap doesn't even cost $100 if you do it yourself. I know this because I recently got my refrigerant license & I had already done a few conversions including my onw truck.
I'll soon be scanning the MACS test book that contains all that info and putting it up on http://www.broncodata.com .
Posting Guru
Joined: Sep 2002
Posts: 2,195
Likes: 1
From: San Antonio, Texas
swap without A/C discharge?
Just to let you in, my fathers been doing it since they ever brought in 134a because he took oil from r12 and 134a, put it in a glass and the oils mixed like they were made for each other. Also r12 as I have seen it,cools better than 134a ever could. I used to work in a mechanic shop a couple of years ago and there was one young mechanic strait out of school that refused to believe me and all the other (vets). *hint, thats what you remind me of.:-)
Personally, I havent mixed the two together in one system, but I have put 134a in a my uncles 81 f-150 and It's been working just fine for around 2 years now. He could'nt afford to buy r12. I'ts getting expensive now days. Thanks for your time mate. Good day
82 Bronco 302cu Lariat
83 Bronco 351w (wrecked) parting out, need the money.
Milk sucks!
Got Beer?
Personally, I havent mixed the two together in one system, but I have put 134a in a my uncles 81 f-150 and It's been working just fine for around 2 years now. He could'nt afford to buy r12. I'ts getting expensive now days. Thanks for your time mate. Good day
82 Bronco 302cu Lariat
83 Bronco 351w (wrecked) parting out, need the money.
Milk sucks!
Got Beer?
Postmaster
Joined: Aug 2001
Posts: 2,882
Likes: 0
From: Nevada
swap without A/C discharge?
I've R&R the engine on my '82 several times without discharging the A/C. After the radiator is removed, I put a sheet of 1/4" plywood against the A/C condensor to protect that and wire the compressor and lines out of the way against the plywood.
Postmaster
Joined: Jun 2001
Posts: 2,809
Likes: 3
From: Loveland, CO.
swap without A/C discharge?
Mine got a new compressor and was converted to R134A. R134 sucks, at least in a system that wasn't originally designed for it. It gets cold, but not as cold as R12. I have heard that you need a bigger condensor with R134. I think people with older cars and trucks should still be able to use R12, as these cars go out of use, so will the R12.
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Postmaster
Joined: Aug 2001
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From: Nevada
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