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How to run old a/c compressor on new legal gas?

LINK17

By LINK17,
in R Series (R30, R31, R32, R33, R34)

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LINK17

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All

I have an 89 r32 gtst, my ac blows hot for the first 10 minutes then works fine? I have looked on sau and run the diagnostic; as per usual amb temp reads -33 degrees. All cycles run fine through diagnostic.

An autolec said it seems to have gas but it is prolly the newer legal gas which runs at a different pressure hence the lag. He said it would need a new compressor and valves/fittings to accommodate the new gas and could cost thousands. 

I have had a skyline for years so I know there has to be a hack - I live in coffs harbour so don't have access to a heap of rb fanatic mechanics.

Any help pls?

joshuaho96 Veteran

joshuaho96

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First verify that you don't have any leaks and the AC amp + AC relays are functioning properly. Then verify that the charge is properly done. You may need to evacuate it entirely and recharge. I believe the dryer and some o-rings need to be exchanged for R134a versions but that should be it.

You will lose some AC performance compared to R-12. If you don't like the thought of that then there is HC-12a which is an isobutane + propane mix. It is highly flammable so if you have a leak in the evaporator you have to roll down the windows immediately, don't believe the marketing claims that it's perfectly safe, it's like having a natural gas leak in your house.

GTSBoy Grand Master

GTSBoy

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I used propane in mine for a while and it was great. But I eventually got the receiver-dryer changed over and ran R134a and it was fine. Slightly not as good, but nothing to complain about.

"Seems to have gas" is not the same as "hooked up to a set of gauges and proven to have the right charge in it".

If you swap to R134a, it is as Josh says above. Also need new adapters screwed onto the charge ports. R134a uses different fittings. Also needs different lube and a sticker on the inner guard.

robbo_rb180 Grand Master

robbo_rb180

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Being an import it should have been converted to r134a at compliance.

As suggested check all fuses and relays. Is the condensor fan working? does it stay cool as you drive? if it does that suggests a faulty fan

Best thing is to take it to a competent auto elec/Ac guy. Get a set of gauges on it and check pressures over its operating temps/fan speeds. Diagnosing AC by forums can't be done properly.

If i was to do it I would check all electrical components and if that does not highlight the issue, replace all the o rings, valves, oil & dryer. Pressure test and vac it down to ensure no leaks or contaminants in the system and regas with around 500gm and monitor pressure and charge from to what that system needs to have around 4 degrees in the vent.

LINK17 Collaborator

LINK17

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Thank you guys, the autolec I took it to said it tested fine for gas, so I'm assuming maybe the dryer hasn't been changed and/or it wasn't flushed completely and it's now running some weird mongrel mix of gases in it. Anyway know of a good skyline ac guy in coffs?!

robbo_rb180 Grand Master

robbo_rb180

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1 hour ago, LINK17 said:

Thank you guys, the autolec I took it to said it tested fine for gas, so I'm assuming maybe the dryer hasn't been changed and/or it wasn't flushed completely and it's now running some weird mongrel mix of gases in it. Anyway know of a good skyline ac guy in coffs?!

All the dryer does is filter the refrigerant of contaminants/moisture within the system. If its only blowing warm/hot air sitting there with no air flow over the condenser it will be an electrical/fan problem or TX valve that is not metering refrigerant properly. The condenser requires airflow to help with the heat transfer as the gas changes states and the TX meters that refrigerant depending on evaporator temps.
As been suggested any auto elec/ac trade should be able to diagnose the issue and resolve it. If you know a fridge mechanic they should be able to help you.

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