Gripes over 134 Retrofit Fittings vice Freon 12 Fittings/AC Questions
 

Is it even necessary to replace the Freon 12 fittings with the New Quick Connect 134 fittings?
I pulled a vacuum for 2 hours and wasted 2 cans of 134 the other day only to discover that my Retrofit 134 Fittings Needle valves weren't making contact with the old R12 Needle valves.
Granted I used Pep Boys Retrofit Valves vice the Mercedes retrofit kit (Does such a kit exist?), but these valves actually worked very well on my other Mercedes.
Then I got wise and just used my old R12 hoses and some fittings and just pumped the 134 using the existing R12 connectors in the System.
Questions
1) Does Mercedes make a Retrofit Fitting Kit?

2) What is the System capacity for a Mercedes 85 300D for 134?

3) Should I still replace the Fittings?

the retro fittings are more for ease of use and to let whoever services the car in the future know that it is a converted ac system. more important is replacing the o-rings and drier, flushing the system then using a compatible oil prior to the initial charge. once you've done all that then you would want the appropriate fittings anyway right?

Yes, you MUST use the fittings, it is the law, yes you can get retofit fittings from MB (and I strongly recommend them, the other's don't work well on the newer cars), and the correct fill is 85% (of the weight) listed on the AC sticker for R12.

Peter

The aluminum ones from most any auto parts store are JUNK! Go to aircondition.com, then click on "straight to the board" then scroll down and click on ACSource. They sell some brass adapters that are the absolute best quality for $2.98 each. I highly recommend them.

I more highly recommend staying with R12 on these cars. It is coming down in price at $29 can and will give you proper cooling.

Don't even consider charging 134 through R12 fittings. You are putting our remaining R12 supply in jeopardy when you do such a thing, not to mention causing someone else down the line a real headache.

If you insist on converting anyway, use the acsource adapters, flush everything, use green o-rings with Nylog lube on them, replace the filter drier, drain all the mineral oil out of the compressor that you can get, put in the correct amount of Ester oil, evacuate and charge. Don't settle for any conversion that shortcuts any of these steps if you want it to last.

And after you convert, you can forget about taking a sweater with you, because you won't be as cool.

Good luck,