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flyingsniffer
19-06-2016, 06:56 AM
Those who were on the Euro trip may recall that I had a/c problems: cutting the belt cured the immediate symptoms but it was clear that there was something amiss down below. Anyway, the a/c systems has never really worked properly so I decided to go through the system, with input from the ever-helpful Kaz. Key actions were
- change the main pipe in the front (I've had it aluminium welded once before but it still showed signs of leakage - found one on ebay, fortunately
- change the received/dryer - Rover 75 unit off ebay
- change the expansion valve- Rock Auto
- change the compressor: the fault was the pulley bearing letting go, but the compressor was not well either. When I took one of the mounting bolts out, refrigerant came out of the hole! Rock Auto
- purge and clean the a/c system - bought a kit with solvent to push through the pipes, inc ase the old compressor had let go some metal bits.

Anyway the purpose of the post is one of those'useful intel' things. The Rock Auto compressor for a 3.2 2000 NSX is 471-1194. However the pulley is wrong diameter and not the right alignment.

A lot of digging around and sleuthing revealed that the a/c pulley for my glorious NSX is shared with that other aspirational powerhouse, the Toyota Avensis 1.8 petrol (1998 - 2000). I bought a s/h compressor (eBay!) for £30 and chucked away the compressor part, just used the pulley and the pressure plate, which were fine.

If anyone ever requires a new compressor from Rock for a 97+ 3.2, I am 99.9% certain that the right compressor and pulley is the 47111128, which is from a 3.4 V6 Toyota Tundra (as the Avensis is not sold in the US). The electrical connection is wrong but that's easy.

I am now in the process of reassembly, except for the blower fan. I'll then get the system evacuated and leak tested. Only once all is well will I put the blower back on.

Hope that helps someone.

Kaz-kzukNA1
19-06-2016, 11:13 AM
OEM compressor is from Denso so not sure why even the Denso Autoparts website shows the wrong info (and obviously, Rockauto refers to it so their website is also wrong) but the pulley/clutch/bracket combination was changed in 1997 and not 2003....

As far as I know, Denso 471-1194 is for the NSX with 1st gen pulley/clutch/bracket for R134a system only (92/93 - 96 NSX).

For the 2nd gen (97+), I think it’s the 471-1193 and it’s for the 97+ NA1/NA2 models but I have never installed this one by myself so I could be wrong.

I tried getting hold of the OEM re-manufactured compressor with OEM pulley/clutch 06388-PR7-507RM from US and Japan but it’s no longer available from both countries and discontinued…..

I already bought the 2nd gen bracket but it’s not an easy task replacing it with the aftermarket header so for now, I'll just transfer my 1st gen pulley/clutch from my 94 OEM compressor to the latest P9K one and keep using the 1st gen bracket….
Hope my aftermarket header won’t cook the new compressor……

Will replace the pulley/clutch/bracket when I take the engine out next time.


Good luck with the reassembly.
Make sure to rotate the clutch many times with hand to prevent compressor lock and too much oil exiting on initial engagement.


Kaz

NSXGB
21-06-2016, 01:26 PM
For reference, the P9K compressor I bought from RockAuto had a pulley diameter of 146mm & grooves are approx 6mm deep. I will measure the 1993 OE one when it comes off again.