Have you used Freeze 12? I wonder how good it really is?
I need to recharge my A/C - I have 3 cans of R-12, but I only have 3 cans.
Doing a retrofit to R134A from R12 is not difficult but it does require attention to detail...And cheap is not a term in a conversion...R134A needs better cooling at the condensor to remove latent heat from the refrigerant and it does operate at higher pressures than R12 did...
The first thing I would do is find a local shop to rebuild the hoses on your truck...20 year old hoses will not withstand pressures for long even if they look like they just came from a 5th avenue bouquet...I would consider replacing the compressor for the same reasons...The condensor is probably not a serpentine design which allows a longer path for refrigerant to travel through it and dissipate heat to help cool the interior air in the evaporator...Now adding an electric fan to the original condensor can help the cooling issue and actually can help even if you go to a later design condensor...A heavier duty thermal fan clutch would be mandatory to pull max air through the condensor and radiator to keep both cooler...And finally an orifice tube and orings throughout for R134A are needed as well...
Obviously the accumulator will need to be changed and current units support both R12 and 134A so that is not a concern...The evaporator is the only component that does not need to be replaced for this conversion...And remember the refrigerant oil needs to be either pag, ester, or synthetic oil like Polyalpha A[my personal favorite]...
Since your Explorer will be very similar to a later model Explorer the capacity of R134a can be based on that later model Explorer instead of guessing by starting with 60-70% of the R12 capacity when converting to R134A...
Now the cost to do this? Well this is where good shopping might help...Used parts for the condensor and compressor from an R134A would bolt on in place of the R12 parts...Accumulator and orifice tube need to be new and the unknown is the hoses...Old R12 hoses impregnated with mineral oil supposedly stop the flow of R134a molecules through the hoses but using old hoses is living on borrowed time imho...
as warmer weather comes on, there are more and more posts on a/c matters. Many refer to conversion of a pre-94/95 r-12 system over to use r-134a. I have cautioned against simply buying one of the $30 kits and doing it yourself if you have no a/c experience. Simply put, failure to properly clean and flush out all the r-12 residue and mineral oil can, and in time will result in a/c failure. Further, you need to properly evacuate the system prior to recharge. Neither flushing equipment nor a good vacuum pump and gauge set are generally readily available to the home diy person - and shortcuts here can spell disaster. Can it be done at home? Sure. Here's a good link all about it.
http://www.glue.umd.edu/~singletn/web/pages/acconvert.html
happy exploring...
Chris
this link is no longer valid from 2003
Thanks, but I got word from a friend that the Gen-1 4.0L OHV Explorers take 36 oz of R-134A to fully recharge. This is, of course, after replacing the compressor and desiccant bottle, flushing the rest of the system with brake cleaner and compressed air. The system will then undergo a 16-hour evacuation, using a Robinaire pump.