I'm in the process of replacing the a/c in the 116. New compressor, r/d, expansion valve, un-wired digital servo upgrade, flushing the lines, etc...

I'm using r12a, which is a drop in replacement for r-12, and supposedly will be a close replacement to regular r-12 and much better than 134.

So my question is...I've noticed on some of the lines I've cracked open, particularly at the r/d and expansion valve, there are no o-rings, but some little copper washers. I've bought all new o-rings...but do I need to replace these washers? Are they a one time use, or will the o-rings replace them?

__________________
1980 300SD 237k
1983 300D 195k (sold)
2003 Chevy Silverado 190k

First off, R12a or FREEZE 12 is NOT a drop in replacement for 12. it's a blend refrigerant of 134a and other chemicals to get better cooling than 134 can in r12 systems. it's one of the "junk" refrigerants. it requires replacement of the oil from the 12 system with ester, or pag oil, and it should have special fittings that are different from 134 fittings, and it requires proper warning labels denoting that it is in there! to prevent an unsuspecting service company from ruining their recovery bottles during service in the future.

next, to your question.
the lines with copper should have new copper crush washers replaced. they are one time use. they will probably work fine if you reuse them, but I'd put in new.

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

well...I'm using ester oil since it came with my new compressor. Why is it considered junk? I've read good things about it, and a friend has put it in his system when he replaced it earlier this year...and it has worked great. I didn't have to use any special fittings, but I am going to label the system in case anyone besides me tries to charge it in the future. I know it's probably not as good as r12, but I think it's much better than 134...

Where would I find those crush washers? Is that a normal auto parts item, or am I going to have to try and find some online to order.

__________________
1980 300SD 237k
1983 300D 195k (sold)
2003 Chevy Silverado 190k

You should be able to find copper crush washers at a general auto parts store, I know Autozone and Napa carry a variety of them.

I read somewhere that if you heated the used copper washer it went back into it's original shape and it could be reused. I should look into that more...

__________________
Steve A
92 W140 OM603
97 VW Jetta TDI
90 Passat variant TDI 6 speed MT
94 Chevy K1500 6.5TD
05 E320 CDI
+ others

Ace Hardware also may be a source of copper washers.
Fuel Injection shops also have a lot of extra one because the Gasket kits they get cover severl models of Fuel Injection Pumps and the do not use all of the Copper Washers or O-rings.

I am one of the ones who said heating the Copper washers Red Hot softens them and the can often be reused (from my old bosses Navy Machinist Manual).
However, I never said it restores the shape. If a Copper washer is deformed or squashed badly heating it will not returnit it to the original shape.
Heating it only softens it.
Also, it does not matter how you cool it. You can let is sit and Air Cool or you can plunge it in Water to cool it; it will still get soft.

This does not work with Aluminum.

However, considering the expense and time an trouble to fix the Air Conditioning system I woudl get good new washers. It is one thing to reuse a Copper Washer and have a Fuel or Oil leak but another to loose all of your refrigerent.
Don't be Penny wise but Dollar Foolish.

__________________
84 300D, 82 Volvo 244Gl Diesel

I didn't read it here.

__________________
Steve A
92 W140 OM603
97 VW Jetta TDI
90 Passat variant TDI 6 speed MT
94 Chevy K1500 6.5TD
05 E320 CDI
+ others

Thanks for the advice on heating....I think I will just replace them. Although...I'm not sure if I can find them locally. They aren't flat washers, but more of a convex...shaped like the end of the hose. I might be able to find them at Ace...I will try NAPA also. I just ran up to my local Advance and they didn't have anything like them.

__________________
1980 300SD 237k
1983 300D 195k (sold)
2003 Chevy Silverado 190k

Well...the more I'm thinking about this, I'm wondering if the proper o-ring size would work fine. I tested the fitting at the r/d by removing the washer, and putting in a proper o-ring. It did seal...

here's some pics of the old copper washer, and an o-ring fitted into where that washer came from on the dryer. It went together find and made a seal.

Attached Thumbnails

   

__________________
1980 300SD 237k
1983 300D 195k (sold)
2003 Chevy Silverado 190k