Automotive Air Conditioning Information Forum

This morning already, before I depart for Prescott, I used aerosol brake cleaner and brushes to clean up the top of the compressor and the fittings, then washed that off with water. Then I took the truck to Home Depot and used the AC. When I returned, I saw a small ring of dye around the bolt securing the high pressure line (the one I replaced in 2017). So pretty sure my small leak is from the O-ring on the high side fitting to the compressor.

I see you list a new discharge line for my truck https://www.ackits.com/1998/nissan-1424 ... -24l-12234 but wonder if I'd need to cut its fitting depth shorter like I did in 2017; anyway, that's not expensive.

Tim wrote: Sat Sep 13, 2025 7:09 am If you can fit it over the pipe and still connect, try a same-size captured o-ring.

I assume that a "captured O-ring" is just one that fits into a groove. I do have an assortment of new green NBR O-rings already.

As I do not have a recovery machine, I'll likely wait until the R134a leaks out, then fix. Capacity is like 2 cans.

Captured o-rings are just a little thicker. Think of it like an old A6 compressor. There are #12 o-rings for the hose connections. And #12 for the back of the compressor, which are thicker, "captured".

Tim wrote: Sat Sep 13, 2025 9:22 am Captured o-rings are just a little thicker. Think of it like an old A6 compressor. There are #12 o-rings for the hose connections. And #12 for the back of the compressor, which are thicker, "captured".

So I may need an O-ring WIDER than the green one shown in this photo that I used, where the factory black one is wider? Or did time just cause the black one to become wider. Because I'm a little confused about thicker and wider here.


1. If so: where do I obtain one without buying the entire hose from you?

2. If I did buy the hose from you and the fitting depth was too long, I'd simply shorten it, and let you know; I wouldn't return it.

I don't know the size of the o-ring off-hand. I always just matched them up in my Master kit. Autozine and Napa are suppliers of Santech, which is one of the big companies where I still do catalog stuff. The issue is that you can't go by my year, make, or model. Kind of have to match it up. The Santech kit for this vehicle is an MT2571. Might look if it has a better-fitting o-ring.

Maybe:
MT0236-4
MT0244-10