The HPCO and HPRV are the same threads. The problem is that this switch is too wide and will not fit behind the compressor. I either need to find one that is narrower or some sort of adapter/spacer that will put the wide part out past the compressor. Does that make sense?

If I replace the valve with a HPCO, I kill two birds with one stone.

What AN fitting would it be to adapt a HPCO?

Well, Here are the pics of the HPRV that came off the truck. It does not appear to be welded. Maybe that is why I had to top it off every 2 or 3 years. Not sure... 20200508_174622.jpg 20200508_174015.jpg I measured it up and the threads are just shy of 3/8". Too small for a 10mm. I am guessing ...

Ice, interesting info. Thanks. B, As far as the HPRV, it was not welded. But it had blown and been replaces a couple times before the HPCO and electric fans were installed way back when. I was running this HPCO on the HP service port. 2A.jpg It took care of both the HPCO and the R134a HP service ada...

Not having a lot of luck sourcing an oring, it seems thay come in packs that caost about as much as a new switch. So, if I have to buy a new switch, I would be interested in moving the cut-out switch to the back of the compressor on the high pressure line if possible. The valve is F1CZ19D644A or Mot...

B, any luck on what that seal should be?

Well, I needed a new line to go with the new style compressor. I guess run it for now. If anything happens I will rebuild without them or just replace it. I think it was only about $60. Interesting info on the mufflers. Odd concept. Please let me know about that seal. I think it is an o'ring. but it...

Also have another question. What seal is up in there? Is it an o'ring?

This is the added high pressure cut off switch that was added with the R134 conversion. It installs on the high pressure line port.

Mufflers? Never would have thunk.

Mine are bigger.

Makes sense on the charging.

So what are those "cans" on the hose? Filters? I am not necessarily a fan of them, but they were on the hose that fit.