I have an 86 420 sel. The A/C has a low charge. There is a hose that is leaking from the drier to the condenser. There is still R12 in the system. Has anyone converted their AC to a R134? I read that it does not cool as well. Or should I stay with R12? The shop quoted about to $200 to evac and charge plus additional labor to change the hose and the drier and the cost of R12.

The other option is spend money on the DIY kit from ACkit http://www.ackits.com/merchant2/merchant.mvc?Screen=PROD&Store_Code=AMA&Product_Code=DIY-STARTER1 to do the conversion to r134 and learn to do this well. With this forum, I know I can tackle this job. Let me know what you guys think. I plan to keep the car as long as possible. Everything else in the car is working great.

Thanks,

John

I have converted 4 cars to 134 with no problems. I did this the cheap way, screw the fitting on the low pressure side and fill her up with one can oil and 134. Probably wouldn't hurt to have it evacuated but I have never done anything else. It's so cheap why not try it.

Dan

__________________
81 240D 4speed with 300D engine
87 560SL
2005 E320
Yukon Denali
Sierra Denali
850 Turbo Volvo
1996 Mustang
1984 Mustang race car
3 Boats

John,

IT really depends on your climate. If you live in the south and do stop and go traffic it will definately be noticably different. You can get an EPA license for R-12 for $15 on-line. R-12 gauges are cheap and the price per pound difference between R12 and R134a is not much this summer.

Do a search on Larrybible- there are some long threads on this subject over the years.


I would NOT convert my car.


Michael

__________________
Michael McGuire
83 300d
01 vw A4 TDI
66 Chevy Corsa
68 GMC V6 w/oD
86 300E

Lots of opinions on this one.

Some say that an original R-12 system will not cool down well after conversion to R-134a.

Others say it will.

There's a member here named Stan Pittman. Look at his profile. 30 yrs. euro car experience. He claims that the 134a conversions do work. I went looking for this thread, but could not find it. In it, he told Larry Bible that he was full of !@#$. Webmaster probably locked down the thread. Stan operates out of South Carolina. I lived not far from there once and summers are hot & humid. If R-134a works there, it will work in many other HOT places.

I believe that a refrigerant conversion is a lot like automotive body work. There's a lot of prep involved and if you do not do it correctly, the job will end in failure whether you're replacing an R-12 system with R-12 or converting an R-12 system to R-134a.

Larry Bible has recently mentioned $14.00 a lb. R-12. He has also mentioned refrigerantsales.com, so I assume he's buying it there. I just looked on their WEB site and a single 30 lb. cyl goes for $575.00. That comes out to $19.16 a lb. - not $14.00. Even in bulk, it's no where near $14.00 a lb., so I guess he's getting it elsewhere.

I saw R-134a the other day for $7.88 - a far cry from $19.16 and a lot more accessible.

Do the job right and R-134a will work.

__________________
'91 300-SEL

I purchased my son's 300e from a guy in South Florida who spent about $3200 on a complete new system with r134a. (evaporator, compressor, high pressure hose,blower, drier)

It blows about as cold and powerful as any car I have ever owned

The replacement parts are the reason why I bought the car....

__________________
1989 300ce 129k
( facelifted front,updated tail lights, lowered suspension,bilstein sports, lorinser front spoiler, MOMO steering wheel, remus exhaust,stainless steel brake lines). (Gone)

1997 s320 154k (what a ride). Sold with 179k miles. Replaced with Hyundai Equus

1994 e320 Cabriolet 108k



1972 280se 4.5 153k Owned for 12 yrs, sorry I sold it


[/SIGPIC]

I believe Larrybible's point is philosophical-

A W124 system holds 2.2 lbs maybe a touch more- say 2.5 lbs. At $20 a lb, that is only $50 for R-12. And if you got your R134a @7.88 (is that a lb or a can?)- anyway we're spliting hairs over $20-30?? Correct.

There is no doubt you can convert it to R134a for $3200 and have wonderful a/c. But why not just replace a leaky hose, a few small parts and have it up and running for $200-300?

I've been in R134 converted cars and most I find inadequate. For W124's they wire the aux fan to be on when ever the compressor is engaged to help.

Michael

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Michael McGuire
83 300d
01 vw A4 TDI
66 Chevy Corsa
68 GMC V6 w/oD
86 300E

Don't listen to anyone who lives in Canada saying r134a is great.
I live in Texas and can say without a doubt that R134a sucks.

Spend the extra 30 bucks and get some R12 from eBay.
It blows about 15 degrees cooler making it worth 10 times the money.

__________________
1984 300D / The only Benz I have

Completed weekend projects

1. R/R front crankshaft seal
2. R/R nearly the whole vacuum system
3. Converted to WVO www.greasemachine.com
4. Upgraded to electric power locks
5. Upgraded and rewired stereo/amp/speakers
6. Installed 2.88 differential

I've experienced that myself and upon inquiry learned that the owner did nothing more than buy a $20 conversion kit. That will definitely result in failure.

All of the succesful 134a converisons I experienced were properly done. Like I said above, do it right and it will work.

__________________
'91 300-SEL

i just went through this. prev owner had converted to 134a. had a leaky hose, so new drier, evac, recharge with 134. 134 didn't cool that well, could only get it to around 50 degrees. in tampa, where it's hot and humid, it was most annoying, it took the car around 20min of driving to get the least bit comfortable. i took it back to r-12, now blows 40 deg.

if you can find a custom a/c shop (one that does rv's, collectible cars and the like) they can probably leak test the system, repair it, and refill it with r-12. i pd $70 per lb of r-12 at the a/c shop and i think it was worth it. the system only holds 2.2 lbs. $140.00 for r-12, vs $60.00 for 134, plus the flush. only worked out to about $50.00 difference. i also noticed that the pressures were about 75psi higher with 134. which equals more stress on the rest of the system which in my case has some 14 yr old parts in it.

you can get a receiver-drier on ebay for @ $20.00. you'll need that regardless of what refrigerant you go to.

also make sure your condensor and radiator are clean. i took the upper tie bar off and pushed the rad back and couldn't believe the gunk in between the condensor and radiator. i used some compressed air to blow it all out.

__________________
"the simplest answer is usually the correct answer"

1991 190e, 2.6 (helga)
91,000 mi

Do a search...

Leathermang and LarryBible are both A/C experts...they have both earned my respect and trust. I will believe what they say on A/C matters.

R134 conversions suck anywhere south of the Canadian border.

My W116 has the conversion...professionally done and it bites....I am converting it back to R12 when I am equiped to do the job.

And the "Drop in Replacements" aren't drop in and they suck even worse.

Do it right do it with R12....

__________________
Proud owner of ....
1971 280SE W108
1979 300SD W116
1983 300D W123
1975 Ironhead Sportster chopper
1987 GMC 3/4 ton 4X4 Diesel
1989 Honda Civic (Heavily modified)
---------------------
Section 609 MVAC Certified
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"He who fights with monsters might take care lest he thereby become a monster. And if you gaze for long into an abyss, the abyss gazes also into you." - Friedrich Nietzsche

In a humid environment, the transfer rate of heat out of the air is much higher. The humidity HELPS the a/c rather than hurts it. It would be much more impressive to have a system that kept a car cool at 90* in Denver on a dry day than Miami or Charleston, SC with their respective humidity levels at the same temperature.

I converted by 300SDL back to R-12; just was not happy with the cooling, especially after being parked outside. The previous owner had it converted to 134a only for the purpose of conversion in '98. The conversion was done correctly (complete flush, etc). I have the receipt and talked to the shop which performed the conversion.

Given my experience, I vote to stay with R-12 on a 126.

__________________
as ever
Paul

1989 560SL
1987 300SDL
1987 300TD
1983 BMW 633CSi
1972 280SE 4.5

I had my mechanic convert the system in my 300E to r134a and I couldn't be happier. Since the conversion I have spent a year in Austin and two in Houston and the car cools as well as it did before the conversion (I would even say it cools as well as when we picked the car up in 94.) The reason I changed is there was a small refrigerant leak in the system that would necessitate a recharge at the start of summer. I decided it was easier just to recharge the system once a year and with r134, cheaper (Altough refrigerant prices have shot through the roof recently?????)

We have been converting to 134A since 1997 and have not had a complaint since. If you do it right you will have no problem. In my experience if done right it cools as good or better than R12.

In my 1992 BMW, i faced this same dillema.

The guys on the bmw forum recommended a product called freeze 12. Apparently its an ozone safe R12 replacement, that is approved by the epa. You can purchase it and install it yourself, no epa certificate required. You can also add to existing R12 without having to evacuate the system.

I've had great results with it in the BMW. All my MB's at this point are R134a from the factory so I dont know how well it works with the MB's.

You can find it on ebay for cheap, a full kit with like 3 cans and the gauge and can tap is like 38 bucks.

Hope this helps,

George

__________________
George Androulakis

Former Mb's:

1990 500sl R129 - 76k Original Miles - New project - Follow the saga http://90r129.blogspot.com/
1990 190E 2.6 148k mi (sold)
1989 420 SEL 246k mi (sold)
1995 C220 175k mi (sold)
1992 190e 2.6 74k original miles (sold)
2000 c230 Kompressor 122k miles (RIP)
1996 C220 149k mi (sold)
2000 C230 Kompressor Sport 127k (sold)

Current Cars:

2009 Mercedes c300 4matic
2006 Mercedes s430
2005 Jaguar XJR
2003 Cadillac Escalade