mindmatter

I have a 91300SL that is not blowing cold air. The mechanic said the following needs to be done:

1. the car has an R12 system and should be converted to the new R134.

Cost: $385

2. Use a dye and figure out where the leak might be.

Cost: unsure

My questions to the group are:
1. Do the 91300SLs actually use the old R12?
2. Is the cost accurate?

Sameer

HaraldZ

My mechanic converted my '90 SL a couple of years ago after he damaged the the A/C system while replacing the head gasket. He did not charge me for the conversion, but $385.00 seems low, considering it takes a new compressor and related items.

mindmatter

So after questioning the mechanic a bit more I found out that he doesn't even do R12 work. That explains why he wanted to convert the car to R134.

Needless to say, I'm sticking with R12.

stonechip

In 1992 Mercedes did the conversion to the R12 system. Upgrading to the R12 from R134 would definitely cost way more that the $ 35.00. Several expensive parts would need to me changed, including several hoses and parts not compatible with the R134 system. Then the entire system flushed, and the new refrigerant introduced.

I would get the work performed by an authorized MB dealer that will provide you with a guarantee that would be more valuable that a guarantee from an independent mechanic.

Check to see the cost, if you are keeping the car I would do it. Production and distribution of the R134 refrigerant is supposed to be completely banned in the near future, if not already done.

a2aa

R129 notorious Evaporator leak issues- It will be cheaper for you to find out first where the leak is coming from before changing parts out. If your evaporator is leaking , this is a 3K dollar job. then it is worth changing over to 134A, If it is just a gasket or fitting leak, fix it and recharge. I did an evaporator change on my r129 '94 equipped with 134A and cost me $1k and 26 hrs of free labor. The dealership charges you 22 hrs@ 75/hr. Do the math. On top of that , if you are converting, additional parts are needed.
FIND THE LEAK 1st. Anyway, R12 is the cheapest part of you A/C system and it cools alot better than 134A. my 0.02.