When I converted my AC System on my 300D over to 134 two years ago, I changed the Receiver Drier. I am using inexpensive Pep Boys compressors which have to be replaced every two years anyway. I am once agian in the middel of replacing the AC Compressor

(1) Should I change the Receiver Driver again? These compressors only last two years.

(2) The system is open to the Atmosphere as of this moment--I ran out of time tonite changing the compressor. Will this deplete the Dessicant?

(3) What factors affect Receiver Drier Dessicant life?

(4) Whats the lowdown on moisture in the System? I know it exacerbates bearing/compressor wear..
Changing Receiver Drier critical to AC success? 1985 300D

I suppose $$ are an issue - can understand that, but where's the value(TIME and $$) changing out a unit every 2 yrs. that might last 10 or more using a real compressor?

I went through this years ago with Auto Zone. $39 alternator for a 1980 Dodge Diplomat. Failed every 3-6 months. No problem. Pull it off and take it back - get a new one. 3-6 months later, same deal. After about 4 or 5(lost track), I broke down and paid about $100 for a real one. Never changed it again.

Receiver-Drier - any time you open the system, change it. Just my 2 cents.

Carrameow,

Not only should you replace the filter drier after any compressor failure, you should also COMPLETELY AND THOROUGHLY flush the entire system to remove debris that will destroy the new compressor.

I have been there, done that with rebuilt R4 compressors. You would be very far ahead by purchasing a new R4, THOROUGHLY flush the sytem, replace the filter drier and then install your new compressor.

Additionally, with the system converted to 134 your high side pressure is significantly higher putting further strain on the compressor. Since it is necessary to flush and replace the filter drier, now would be a great time to reverse convert to R12.

Best of luck with it,

Rule of thumb on drier replacement; system open for more than 24 hrs, drier more than 5 years old, OR unable to vacuum system for 24 hrs! OF course this day & age NO one wants to vacuum system for 24 hrs.

Moisture is the DEATH of any A/C system.

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If one can vacuum the system for 24 hours, does some of the desiccant get revived, or is it only good for one reaction?

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1986 300E 5-Speed 240k mi.

Larry, I wouldnt mind using R12. the only problems is that its hard to locate. If you know of a source.........anyway I am dreaming of moving to New Mexico from New Jersey and maybe it wont be so humid and I wont need AC anyway

r12 is easy to buy.
You just need an EPA 609 certificate.

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1986 300E 5-Speed 240k mi.

New Mexico is bone-dry. Beautiful place. Humidity is non-existent compared to other places.

It does get hot - you will need A/C. Desert heat.