A/C on 91-92 cars

[NotFast]

Hi all:

Does anyone have any good/bad experiences with the CFC refrigerant on the 91-92 MY cars? I've heard that recharging them on other cars is expensive (or next to impossible) and converting systems to R134A is usually expensive. Has anyone had to refill the freon and/or convert? Any idea on costs?
TIA

 

[winreboot]

I use 134 on my 91. You have to emply the freon in your car with certified station. DON'T LET FREON IN TO ATMOSPHERE.

Then we vacun the AC system put 134 oil and 134 gas and that was all to it.

Acura sells conversion kit that is like $100

 

[nsxtasy]

Converting to R-134a is inexpensive and easy with Acura's conversion kit. People who have done so have gotten good results using R-134a.

For those with the '91-92 cars, I would recommend waiting until there is an A/C problem of some sort, and then doing the conversion.

 

[bobyang]

I converted my 91 to r134 a few months ago. Here is what i learned through conversations with Don at Hilltop (who did the conversion) and Eric at Niello Acura (who I got the parts from):

-if you dont replace the compressor, the conversion tends to spring leaks after a while and you have to do the compressor anyway. Something in the oils.

-If you replace the compressor, you should get the same compressor plus conversion kit instead of one from a later car. Originally, we were thinking of installing a compressor from a '96 or whenever Acura switched over from r12. The newer compressor costs about twice as much.

-it cost me about 750-850 for parts and labor, I think.

hope this helps.

oh, and I believe R134a is cheaper than r12

[This message has been edited by byang (edited 03 January 2002).]

 

[burbel]

byang, thanks for the info!

My compressor had a small leak a year ago; now it's shot, so I need to replace it, and, while doing that, I'll also move to R134.

Would you recommend replacing any other pieces with the compressor? Or should I do the fix/conversion and wait for the next part to fail? (knock on wood!)

Thanks!

 

[NSXTech]

If "shot" means that it is making loud sickening noises, or even a loud rattle or hum when engaged, you MUST replace the rec/drier and the expansion valve, as well as flush (with a professional a/c flush tool made for this purpose) the entire stystem including evap (with exp valve removed) all lines with NO exception, and both condensers. This would be the time to convert, but if you have a noisey compressor and do not do a major complete flush, you will be doing the whole job over in a few months when the residue of the bad compressor travels throughout the new clean system and makes it a new old dirty system. This is the cheif reason that more NSX owners who contact me for advise- 6 or more a week this time of year- do so; their dealer is telling them that they need a whole new system. EVERYTHING! Hoses, condensers, compressor, evap, drier, etc. Castrol, as well as other companies make a great product called A/C system Flush, for conaminated system. The tool is not expensive, but requires a fairly high powered, long winded (storage capacity) compressor to operate. If you want to do some DIY on the job, remove the blower to access the expansion valve (don't let your dealer BS you that expansion valve requires dash and evap removal, I get that call several times a season). Discard the expansion valve. Remove the rec/drier- discard. open the fittings between the pair of condensors and both lines (do NOT discard.) And lastly, remove the fittings from the compressor. If the compressor is bad/was very noisey, discard it. Find an a/c shop who will flush everything for you with professional grade equiptment and people, take with you some small baggies and tie wraps to seal the clean system for the ride home.
After you install all your parts, take it back to the guy who cleaned it for you, and have him charge it. The kits they sell for DIY a/c system charging is really a bad idea. You need a really good set of gauges to do it right, plus a vacuum pump to remove all the air, moisture, and possibally residue of cleaner. (A/C cleaner is one of those zero residue,MOL, like brake clean, so there should not be much. But there are alot of low point traps in the lines where liquid flush can stand- make sure it is ALL blown out. It will displace freon and diminish your cooling capacity.

With an ambient temp of 100 degrees and a humidity of say, 40%,
the temp coming out the vent should be about 43 degrees if all is well. And that is not on high speed fan- temps go down set to high because of lowered "dwell" time. Test at 2/3 fan speed on recirc only, best with car moving to augment condenser fans with fresh air movement.

 

[nsxtasy]

That's great information, Mark - thanks for posting!

 

[nsxtasy]

P.S.

With an ambient temp of 100 degrees and a humidity of say, 40%, the temp coming out the vent should be about 43 degrees if all is well.

Some of us would need to drive 1000 miles south to perform that test...

(Current mid-day temperature here: an unusually cool 63 degrees F)