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Most people would cut the hard line fittings from their old MR2 lines (as I did) and crimp the new hoses onto them - which is a shame because it destroys a perfectly good set of lines that could be put to use in another MR2. In your case, the a/c system was deleted previously so you had to find new fittings. Those new fittings are a pretty good find. It would be great if you could come up with part numbers for those. Nice job on restoring your a/c.
 

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That 45 degree fitting should be perfect that's the angle I ended up bending mine.

Here is an update added later in case anyone is trying to hook up a 95-95 system. The ac lines are a different size from the 91-93 listed here.

93 and earlier fittings are 7/8-14 and 3/4-16, the ones on the 94-95 22 & 24mm.

Fittings for the 94-95 may be available here but this has yet to be tested.
https://coldhose.com/collections/female-oring-metric
 

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Besides the a/c clutch, the 2GR ECU also controls the pressure relief valve or whatever it's called. This thing is a royal pain in the rear. It needs to get 12v in order for the pump to make pressure, otherwise it just vents it out, so you need to wire it up like that. The other option, which I believe Marc used originally, is you remove this valve, modify it somehow, and put it back, so it does not need ECU input to switch on. Probably you can find the thread where he did this if you search. Personally I had the wonderful experience of blowing up two 2GR compressors within minutes of installation so I would never use a 2gR compressor again. My 1GR compressor has been on the car for two years and revs to 8000rpm all the time without any problem.
 

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I have no idea how I acquired this document. It does seem authoritative - possibly came from a Toyota TSB. It spells out the oil and refrigerant quantities for R134a conversions on various Toyota vehicles. Get out your metric to SAE conversion charats. If you need help, I can convert g and cc to lbs and fl. oz. for you, for a fee. Ha ha. Ha ha ha ha.

75414
 

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I've seen your other posts. The first one regarding the relay, and the newer one regarding the amplifier. The amplifier needs to trigger the ac clutch relay. There is a amplifier troubleshooting section in the BGB. If you don't have it or cannot find it I can get it for you (what year is your car.) If I recall correctly, the rpm signal for the amplifier comes from the instrument cluster aka combination meter. [I recalled incorrectly. There is no rpm signal to the amplifer. Corrected in later post, with details of how the amplifier detects engine running condition]. If your tachometer is displaying rpm then chances are the rpm signal is going from there to the amplifier ok - but this bears verifying. You can use a test light on the rpm terminal on the amplifier to verify. The signal from cluster to amplifier is not affected by the 2GR harness or ECU. LIke the radiator fans, it functions completely independently of the ECU. On my car I had an amplifier issue that affected the fans, not the compressor. I was able to get a replacement amplifier from a partout, and fortunately it worked. Your other option if you have an amplifier fault and you cannot find a replacement amplifier is to wire a dash toggle switch in-line with the pressure switch to trigger the ac clutch relay. This way you do not risk burning up your compressor if you have too much or not enough refrigerant pressure.
 

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This is an update with regard to fittings for MY 94 and 94. The fittings for the ac lines at the firewll are a different size from 91-93 listed earlier in this thread.

93 and earlier fittings are 7/8-14 and 3/4-16, the ones on the 94-95 22 & 24mm.

Fittings for the 94-95 may be available here but this has yet to be tested.
https://coldhose.com/collections/female-oring-metric
 
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