R134 or R12 thoughts

[Redrig]

Hey all ,

My daily driver is a 91 ford bronco , at the end of last summer my compressor crapped the bed. I am going to be redoing the entire system. New compressor (not rebuilt) all new hoses , drier , flush condenser, vacuum down overnight , etc.

The bronco was born an R12 system , the previous owner converted it to r134 many years ago , I have had it about a decade and AC always OK , not great but OK. That got me thinking , If I am going through the pain of doing all of this , should I take it back to R12 ?

R12 is still available and not terribly expensive , I am leaning this way simple because I hear that R12 runs at lower pressures and is easier on the compressor, I dont want to do this again in 2 years.

r134 is certainly more available at any store . But like I said , its not impossible to score R12 either.

any thoughts ? Thanks

 

[matt167]

Being a '91, just find some Freeze 12 and convert it back

 

[Earl Cordova]

I don't think it would be worth the cost to switch back.

 

[matt167]

I don't think it would be worth the cost to switch back.

it's removing a couple adapter fittings and putting in the original schrader valves. Those valves are not vehicle specific. Trip to the junkyard would get a handfull of them

 

[GA_Boater]

How much does Freeze 12 cost vs R134a? What about the oil?

 

[matt167]

Freeze 12 is banned I think, but there are still many to be had. Facebook marketplace showed dozens at $12-25 each

the problem with 134A in a 12 system is the pump is designed for 12 and when you run 134A, the pressures are off. It will never cool cold, always just ok. If this were a round dash model ( 1992 -1996 ) then it's easy as the entire AC system can be swapped from a 134A truck to an R12 truck

 

[Scott Danforth]

if the compressor is bad, just change the compressor and the h-valve and be done with it. go full R134. the condensor and evaporator dont know or care. the lines need to be properly crimped either way. since your compressor needs replacing. that is where the cost is to convert to do it right.

 

[Redrig]

if the compressor is bad, just change the compressor and the h-valve and be done with it. go full R134. the condensor and evaporator dont know or care. the lines need to be properly crimped either way. since your compressor needs replacing. that is where the cost is to convert to do it right

Thanks for the feedback all.

Scott , what is the h- valve ? That's a new one for me.

It sounds like I may be reading into the lower pressure of 12 , more than needed.

 

[Scott Danforth]

its the expansion valve. about $25 for your ford bronco

 

[Redrig]

its the expansion valve. about $25 for your ford bronco

Gotcha , sorry just difference in terminology . Yeah one of those is in the old rockauto cart . Red orifice tube as well

 

[Scott Danforth]

you have a vac pump and manifolds, right?

 

[Earl Cordova]

it's removing a couple adapter fittings and putting in the original schrader valves. Those valves are not vehicle specific. Trip to the junkyard would get a handfull of them

Maybe I'm wrong, but I had converted over several old Fords from R12 to R134 and it was expensive, so I assumed the conversion back would be the same.

 

[matt167]

Maybe I'm wrong, but I had converted over several old Fords from R12 to R134 and it was expensive, so I assumed the conversion back would be the same.

if you buy just the conversion kit, it's basically the schrader valve adapters and the freon.. But done correctly, it would include the correct pump.

 

[Earl Cordova]

When I did mine the compressor was over $500, which to me is expensive.

 

[Redrig]

you have a vac pump and manifolds, right?

Rentals from o'reilly is the plan there

 

[matt167]

When I did mine the compressor was over $500, which to me is expensive.

which is why most of the conversions are done with the $49 kit that has the valve adapters and a few cans of freon. Not as cold, but colder than none

 

[Earl Cordova]

which is why most of the conversions are done with the $49 kit that has the valve adapters and a few cans of freon. Not as cold, but colder than none

So when it is 115 degrees outside it sounds worthless.

 

[matt167]

So when it is 115 degrees outside it sounds worthless.

It would actually cool better at a higher temp due to the pressures. I've only ever converted one vehicle. It did not cool when the ambient was below about 70*, but if it was over 70* it would be 20* colder out of the vents.. 115* where I live is a very rare occurrence.