RV2 plumbing question

5wndwcpe

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So I'm in the process of replacing the O-rings on my a/c system ('69 300) when I hit a snag at the discharge line, leaving the compressor.

When I took it apart, there was an o-ring, but no flat gasket.

The fsm shows a flat gasket, but no o-ring at this juncture.

The kit I received for Original Air Group has both an o-ring and a flat gasket.

I believe an o-ring should be used as there is a recess for it but do I use the flat gasket as well ?

Normally I would defer to the fsm, but since it differs from what is actually on the car, I'm curious as to what has worked for the forum members in the past.

P.S. The car is bone stock and I see no evidence of this having been apart or swapped out before, so I'm thinking it's original.
 
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It originally had a flat metal crush gasket. Crush gaskets can only be used once. They're around but impossible to find.
I talked to OAG about their gasket and they said it was "good enough".
I disagree.
 
Okay, so I just got off the phone with OAG and they said to use one or the other, but not both (which was my inclination anyway). I'm going with the o-ring only as that is what was there to begin with.

I don't know why the fsm differs, mid year change perhaps, but it does. :rolleyes:
 
My 70 300 had the o-ring. This is the (very) high pressure side of things. The PN is 3441513, and it's available from here for $5:
NOS Mopar Parts

My suction side ALSO had the recess for the o-ring, but the paper gasket on the suction side (along with the screen that goes in the suction fitting) is sufficient for that pressure situation. Bolts get 12-14 ft lbs on both sides.

And yes, the FSM is goofed up about this, and it got me confused until I looked things up in the 70/71 Parts Catalog. I figure that same FSM illustration had been in manuals since the mid-60s.
 
Nigel at National Moparts has the correct gasket.

1-888-652-7464
So does FJC in North Carolina. FJC Inc – Air Conditioning Products, Tools, Equipment Power Division

Search Results for “4131” – FJC Inc
or
Search Results for “4144” – FJC Inc
Anybody know why that little tab is in the bolt holes? To hold it to the flange during assembly, maybe?

They also have this Search Results for “4144” – FJC Inc which might work better on some discharge flanges....dunno.
 
NAPA has the correct gasket available.

Well......THAT makes it easy!

I used an NOS O-ring with no other gasket (from Central Jersey Motor Parts) and I think it didn't seal perfectly. Fluorescent dye shows a very slow leak. So I'm going to inspect the flange even more that I did the first time (flatness, pits, high spots) and use the metal embossed item. I sure don't intend to use the paper gasket that came with the Four Seasons reman RV2.
 
Yup, bend them down into the bolt holes to keep them in place during installation of the pipe flanges.

Remember - these are "one use only" gaskets - even a mild torquing then removal reuse will render it useless.
 
Yup, bend them down into the bolt holes to keep them in place during installation of the pipe flanges.

Remember - these are "one use only" gaskets - even a mild torquing then removal reuse will render it useless.

Do the tabs go into the Lung or the Flange?

And I'm with ya on "single use". Just to be sure of a seal, I might even spray a thin layer of "Copper Coat", which is what I've used on embossed steel-shim headgaskets for decades. I don't want to continue using 3 lbs of my precious R-12 while I try to sort this issue.
 
I would say the flange, as there are no threads to gall... and the copper coat will help it stick to the flange as you're bolting it together. Good idea.
 
I would say the flange, as there are no threads to gall... and the copper coat will help it stick to the flange as you're bolting it together.

Yeah, can't remember if there's a counterbored area in the bolt hole of the Lung for those tabs, or if the threads come right to the mounting surface. They seem kind of pointless to me, because it's not like it's hard to hold a silly little gasket in place whilst you start the bolts.
 
I understand this is an old thread. But I would love to know if the compressor discharge hose o-rings are available from parts stores? Also If I could get a number?
I looked the part number up in my book and find no results. P#2008388
Thanks.
 
This o-ring is NOT in any auto AC o-ring packages at the parts store, green rubber or otherwise because those o-rings packages are for all the various hose and hard line compression fittings, not this unique-to-Chrysler RV2 discharge flange.

The o-ring is not a Chrysler specific size (why would they do that back in 1965?). Industry calls it a "-021", as in "dash 021". Material was neoprene. The nominal size is 15/16 ID, 1 1/16 OD, 1/16 D (cross-section). Easily bought online (probably in packages of 50!) now that you know what you're looking for.

The current Mopar PN is now 3441513. Central Jersey Motor Parts Central Jersey Motor Parts has them. $8 last I bought one. Guy who owns the place and answers the phone is Jack Koziol. He has all sorts of hard-to-find small parts...and large parts, too. He's a true resource and a good guy.

Or, if you think your flange is dead-flat perfect, you can use the steel embossed gasket sprayed with several thin coats of KopperKoat gasket sealer (it goes by several names by several vendors. Permatex calls it Copper-Spray-A-Gasket). The layers of dried copper/shellac really make for a good seal with the existing embossing.

But what about that perfect flange? Eyeing the flange's flatness with a steel rule will not tell you what you need to know. Buy a brand new cheapo coarse whetstone at the hardware store and run it across your flange (put a bit of wadded cloth into the line to keep crud out of the system). Is the pattern perfect, or are there highs and lows? If so, spend the next six hours flattening that flange with that oiled whetstone. Ask me how I know all this.
 
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