I'm restoring the a/c system on my '73 340 Duster & thinking about converting it to 134a.Does anything need to be changed / modified / updated to the compressor when going to 134a refrigerant ? I understand that the hoses,orings & oil need to be compatible,not sure about the compressor itself.Will the compressor's crankshaft seal work with 134a?
Stock compressor,mod for 134a ?
- Thread starter rod440
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mderoy340
Well-Known Member
It will work fine.
I just found out that I have the wrong compressor. I have an RV2 compressor,originally it would have come with a V2 compressor. The main difference is that the RV2 has larger bores/pistons than the V2. It looks like V2 was only used on A bodies. Could the RV2 be used on the A body without any problems?
mderoy340
Well-Known Member
It will work. The expansion valve will control refrigerant flow. The cycle temp probe in the evaporator will cycle the compressor as needed.
lemondana
BlackDart
Go to a swap meet, buy 4 cans of R12 and use that! You will be a lot happier and cooler!
slantsixdan
=..=
There's a lot to get right or wrong on a job like this. See here, here, here, and here for the info you need to do an optimal-working R134a conversions on an old Mopar. If you were working with a '74 or newer A-body factory A/C system, you'd have to remove the EPR valve and install a clutch cycling switch, but A-body factory A/C had a clutch cycling switch and no EPR valve thru '73 -- the dealer/aftermarket "hang under the dash" systems have clutch cycling switch and no EPR regardless of year.
To answer a related question: Use R12, or do a proper conversion and use R134a. Don't use anything else. Any of the hydrocarbon (isobutane/isopropane) "refrigerants" -- "HC-12a", "RedTek", "OZ-12", etc. -- is a very seriously foolish gamble, and the "Colonel's Secret Blend of 13 Herbs and Spices" blends like Freeze-12, FRIGC, etc. may work in the short term, but their various ingredients leak at different rates, changing the composition of what's in the system so you can't just top up and have it work well...and most shops will not touch a system charged with something other than a legitimate refrigerant (12 or 134a).
To answer a related question: Use R12, or do a proper conversion and use R134a. Don't use anything else. Any of the hydrocarbon (isobutane/isopropane) "refrigerants" -- "HC-12a", "RedTek", "OZ-12", etc. -- is a very seriously foolish gamble, and the "Colonel's Secret Blend of 13 Herbs and Spices" blends like Freeze-12, FRIGC, etc. may work in the short term, but their various ingredients leak at different rates, changing the composition of what's in the system so you can't just top up and have it work well...and most shops will not touch a system charged with something other than a legitimate refrigerant (12 or 134a).
BillGrissom
Well-Known Member
Why convert to R-134A when it has been outlawed for years in many countries and phasing out in 2017 in the U.S.? I have Duracool HC refrigerant in all of my vehicles now. I converted the 1996 & 2002 after their compressors failed. I have used it in my 1965 Newport since 2002 (after R-134A). Many claims it can "explode" from people who nothing of combustion (AC shops), but no reported fires after use in millions of cars for many decades, except an Australian AC guy who manufactured a fire. Whatever refrigerant you choose, consider PAO 68 oil since more efficient and doesn't absorb moisture like PAG does.
slantsixdan
=..=
• It's highly compatible with existing systems
• It's one of the two legitimate refrigerants for A/C systems in old cars (anything else in your system and any shop worth letting touch your car will order you off their premises)
• It's safe
• It's legal
• It's cheap
Those are five very sturdy reasons.
It's being phased out for new cars, but will be available (and inexpensive) for servicing existing systems for a very long time. The refrigerant being phased in for new cars, HFO-1234YF, requires extremely different A/C system hardware than R12 and R134A.
That's a hydrocarbon blend. It does not belong in your A/C system, which (unlike your fuel system) was not designed or engineered to carry or transport a highly flammable working fluid. Using this stuff is not clever, it's super extra foolish for all the reasons already covered.
Of course those who market it promote it as completely safe, don't pay attention to any of those scare stories, blah blah don't pay attention to the fact it's not approved, blah blah conspiracy by the refrigerant industry blahbitty blah blah blah. Because yeah, highly flammable hydrocarbons under high pressure are safe, because, um, because, uh, because, um, it's made with special smart grades of isobutane and isopropane that, um, they, uh, know not to explode when they're in an A/C system!
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