A/C Compressor to Hose O-Ring Question...

mustangmarty

Veteran Member
Joined
Nov 9, 2016
Location
Central Texas
TDI
1996 Passat Wagon TDI
I’ve just finished replacing the RCV in my 1996 B4 and I notice that the O-rings between the compressor and the lines out the back don’t look like O-rings at all. To be honest, they look more like turquoise colored garden hose seals and they don’t even come close to fitting snug around the metal part of the AC line that protrudes into the compressor. They seem way too big. Is this normal? I ordered seal kit # GA 4675 KT, and there’s nothing in this kit that looks like the seals that are on there now.

Upon looking closer, I see that the SD7V16 compressor has a rectangular groove around each ac hose port that these seals fit perfectly into, so I believe they are the right seal. However the seal kit I have doesn’t have these seals in it. It only has the big housing gaskets and a bunch of regular orings. Should I replace the existing correctly fitting rectangular seals with regular orings? Or reuse the rectangular seals I have? Or order a different seal kit. Advance Auto can order a kit that looks to have those rectangular seals included.
 
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Mongler98

Top Post Dawg
Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
as long as the thickness is correct, make an oring fit is how its done. you can get fancy and heat it up but the trick i use it a TINY dab of super glue in the corners, you can heat up the part to remove supper glue EASY on the next go around or a mistake.
 

mustangmarty

Veteran Member
Joined
Nov 9, 2016
Location
Central Texas
TDI
1996 Passat Wagon TDI
Thanks Mongler, it’s starting to look like what I’ll have to do. After looking at the AC line O-rings at Advance Auto and the other part stores, they all only have circular o-rings. No one has or can get rectangular o-rings.
 

ToddA1

Top Post Dawg
Joined
Aug 3, 2011
Location
NJ 08002
TDI
'96 B4V, '97 B4 (sold), '97 Jetta (scrapped)
Rectangular? Are you referring to the cross section?

I’ve used the standard o-rings from the parts store and never had an issue.

-Todd
 

iluvmydiesels

Veteran Member
Joined
Nov 21, 2015
Location
phila area
TDI
AHU
A/C oring seals are a type of green these days.
as far as the specific oring you may want the exact fitting one. if its size is the same, ?take a chance?
i dont know about a heating trick. when installing A/C orings make sure they are lubed. use right oil.
 

Mongler98

Top Post Dawg
Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
yea supper glue will easly come off any metal part if you warm it up to like 250 ish degrees F. So you dont have to worry about that for your next service on that oring. Purple is the AC oring colour that is easily found, Green is the older type that (if im not mistaken) also workes on R12 as well as 134a. the reality is that as long as its not a black oring, you can use the red, green, brown, purple, or yellow. they all have the same application and oil resistance for your need. i prefer purple though, 340K miles on purple orings my MK3 and still running strong, well last i drive it before i blew the turbo, but thats another story.
 

iluvmydiesels

Veteran Member
Joined
Nov 21, 2015
Location
phila area
TDI
AHU
purple or green orings dont fit on a turbo blown and spilling oil over an engine, from an open pipe so you can make it just far enough down the road to make it home--,or not (blown). heheh, jk.

seriously dude if an open flame or that heat isnt a fire hazard.
open flame or that amount heat on A/C parts, is that smart?
 

Steve Addy

Top Post Dawg
Joined
Aug 7, 2002
Location
Iowa
TDI
97 Mk3
Thanks Mongler, it’s starting to look like what I’ll have to do. After looking at the AC line O-rings at Advance Auto and the other part stores, they all only have circular o-rings. No one has or can get rectangular o-rings.
They start life circular, or round, and after compression for years they end up being rectangular.

Get some round replacement o-rings you'll be fine.

I ordered a full system kit of o-rings from RA and they were all purple, all of them. Also they were all round. Also there were so many extra that I probably have enough to do another car.

Steve
 

Mongler98

Top Post Dawg
Joined
Mar 23, 2011
Location
COLORADO (SE of Denver)
TDI
98 Jetta TDI AHU 1.9L (944 TDI swap in progress) I moved so now i got nothing but an AHU in a garage on a pallet.
They start life circular, or round, and after compression for years they end up being rectangular.
Get some round replacement o-rings you'll be fine.
I ordered a full system kit of o-rings from RA and they were all purple, all of them. Also they were all round. Also there were so many extra that I probably have enough to do another car.
Steve
I thought the same thing but when i did my vans AC with that pack i found that i used most of the ones i needed. the $3 bucks for a pack, i end up at the end of a year with a 1 gallon bucket of the larger sized ones that go in the trash as need mostly the smaller ones.
 
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