Dual AC

"" wrote: > I Have a 1985 Gmc conv Van With Dual Ac And it needs a retro > fit to put new > freon in it ,and the chevy houses want about four hundred > dollors to do > this,But here is my dallima we are on a fixed budget.so a > friend told me i > could bye a conversion kit to do this my self from checker > auto for about > 60 dollors,but an ase certified mechanic says they will have > to replace > both dryers and valves to convert this over.so my friend says > to have it > evac and then bye the conversion kit and do it my self.Is this > doable for > me.

You do not need to replaced dryers for a conversion but you do need the vacum down the system. (No way around that) Why are you converting? If you are low on freon even at totadys price you should be able to get R12 replenished for a lot less than 400 bucks and beside if you switch over to R134, cooling performance will degrade a noticable amount because R134 has a lower heat content than R12 and a different pressure curve too. New R134 system have different compressors and bigger condensors and evaporators to make up for this efficency loss you old R12 system does not. I would only convert to R134 as a last resort as there are some other option out there for R12 systems that are better than R134 but all of them require system to be vacumed down.

I'm not here to debate anybody but $400 does not sound like an unreasonable price for a duel system. I had my 1983 Continental Mark VI converted to R134 last year, at a Lincoln dealership. They changed some seals, evacuated the system and refilled it with R134 for $185 plus tax. It is still working fine a year later. I too was told it would not be efficient, however I have not noticed any deterioration in cooling ability. In fact it apparent to cool down a hot car more quickly than does my 2205 Lincoln LS or my 2005 Mustang GT

mike hunt

SnoMan wrote:

Thx guys I was told they did away with r12 freon.we just bought this conversion van and it sat for 9 years in a shed,And the air wont cool.so i will go to checker today and bye a r12 kit.

Systems such are the one on the connie have more reserve to begin with when they are new. They will do better with R134a than some other systems will. It is a fact of physics that R134a has about 15% less heat moving abilty by volume than R12 does and it has a higher pressure to and you have to add oil (in effect, over charge your system with oil) because R134 is not compatable with R12 oil and will not carry it through system. You add a oil to it to bind to the R12 oil and to allow it to be better carried by the R134. The best way to convert a R12 system to R134 is to empty system of oil, replace compressor and change expansion valve to flow about 10% more freon to minimize losses but there are some after market freon replacement that are compatable with R12 oil and do not require a oil overcharge to work and have a higher heat absorbtion abilty than R134 too. A dual AC van has a lot of heat to move and if converted to R134 it may not cool properly.

thx snowman,were i live for some reason these garages want to tell me a lot of money to change this system over wich aint bad as yall say.so I'll just take it out of town to a big city and have them service it thx.loyd

Actually on an 85 you WILL have to change both the front and rear driers the desiccant in them will not work with 134A. Also the rear valve has to be changed as well as the front orifice. Without those items being changed you may as well not bother. The conversion kits work BUT only on vehicles that really don't need any changes (basically 90-94 GMs, 90-93 Fords and 90-95 Chryslers since they have parts that should work OK with 134A because the factories were in conversion during those years) and that are not leaking anyway. R-12 is still around ( I just bought a 30# tank last week) NOT CHEAP. Retail it runs about 70 dollars per pound BUT you don't need a lot. My

95 conversion uses 4.2 pounds. of 134A. Keep in mind that the rear AC used on 99% of conversions is NOT a factory unit, they are aftermarket units. They use vehicles that were ordered with rear air fittings but no rear AC/heat unit.

I would just have them refill it with R12, it may cost 30 or 40 bucks a pound but it will be a lot cheaper than converting the system over when you are having to hire it out.

thx steve but i dont have a lic to buy it in my state to recharge it my self.

so steve can i request to have a garage put R19 in it,we use this conversion to take long rode trips out of our home state to see family in az and ca.and its really hot on that az desert if you nkow what i mean.

IF you know how to recharge it you can get your 609 certificate online for 20.00 Real easy to do just download the book and take the test.

Saw the question about R-19? Never heard of it. Basically IF you want it to be serviced by any normal shop your choices are R-134A or R-12. Most shops won't even hook onto a vehicle with any of the blends in them.

Personally I'd just find a shop and have them vac it down, check for leaks, recharge with R-12. Probably should have the compressor seals replaced considering the year. Should run about 150.00 or so plus the cost of the seal repair. Then you would be right back to original condition. With a conversion van you need all the cooling you can get. Especially if you have leather interior. Mine has Dark blue exterior and Royal blue leather interior. Let it set in the sun a bit and you could cook inside the beast.

For about the same money you can buy a rebuilt compressor. I would be a better investment top replace compressor given its age if it does have a seal problem.

thx steve its cloth interior but still can cook an egg on a very hot day,I meant to say R12.thx steve and snow man.I have a problem with that 97 dodge with that check engine light on.120 miles its using about about 3/4 of a tank of fuel and i use it to work with.it has a 318 fuel injected in it.

I found some one that will fill this conversion air with r12 freon and oil thx gentleman.