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Home » Public Forums » GMCnet » Sanden vs A6 compressor (And other a/c rebuilding topics)
Sanden vs A6 compressor [message #122338] Tue, 19 April 2011 12:08 Go to next message
Rick Williams is currently offline  Rick Williams   United States
Messages: 256
Registered: July 2004
Karma: 0
Senior Member
I just read Michael's post about what he learned at Patterson so I thought I would start a discussion about rebuilding the a/c system. I am curious about Ken H's discussion. I know he is using a Sanden clone.

The A6 is a large compressor at 207cc. There are some Sandens that are 160cc but there are others that are much smaller. What size have people used?

My A6 has a front end leak and a noisy clutch. I would just as soon try a new replacement as to spend time and money rebuilding it. The Sanden SD7H15 is 155cc. It is available with a GM hose fitting.

The Sanden comes filled with Sanden SP-15 PAG oil. It has a viscosity of 80 cSt at 40 deg. C. Sanden says to use only Sanden oil. PAG oil varies in viscosity. GM Goodwrench PAG 150 oil comes from Dow just as Sanden does and is chemically the same except for viscosity. How important is the viscosity issue?

My system has had both R12 and 134 refrigerants and mixed oil. So I will need to flush the system. I have read that it is ok to use mineral spirits as a flush. I have also read not to use it and to only use a/c flush solvent. Opinions welcome.

I know that I have to replace the accumulator and remove the expansion valve before flushing but should I replace the expansion valve? With everything made in China these days and given some of the experiences that I have had with Chinese auto parts, my first thought is to reuse the expansion valve. Can it be cleaned effectively? I have no idea what I will find when I start flushing. I find references to "Black Death", the resulting goo of mixing mineral oil and R12 with PAG or ester oil and 134. What is the total oil quantity requirement for our system?

I will be using Duracool.

Thanks to all of you for your help.

Rick


Rick Williams
Bliss, Michigan
1978 Eleganza II
Re: [GMCnet] Sanden vs A6 compressor [message #122342 is a reply to message #122338] Tue, 19 April 2011 12:24 Go to previous messageGo to next message
Gary Worobec is currently offline  Gary Worobec   United States
Messages: 867
Registered: May 2005
Karma: -1
Senior Member
When I redid my AC system and installed the Danhard under dash unit I
specifically wanted to keep the A6 as it has enough volume to be able to
drive another condenser at the rear of the coach. My AC guy said it is just
a simple matter of Teeing into the high and low pressure sides up front and
running new hoses/tubing down the inside of the coach to the rear. This is
on my list of "to-dos" this summer.

Thanks

Gary and Joanne Worobec
1973 GMC Glacier
Anza, CA




----- Original Message -----
From: "Rick Williams" <rickw@mich.com>
To: <gmclist@temp.gmcnet.org>
Sent: Tuesday, April 19, 2011 10:08 AM
Subject: [GMCnet] Sanden vs A6 compressor


>
>
> I just read Michael's post about what he learned at Patterson so I thought
> I would start a discussion about rebuilding the a/c system. I am curious
> about Ken H's discussion. I know he is using a Sanden clone.
>
> The A6 is a large compressor at 207cc. There are some Sandens that are
> 160cc but there are others that are much smaller. What size have people
> used?
>
> My A6 has a front end leak and a noisy clutch. I would just as soon try a
> new replacement as to spend time and money rebuilding it. The Sanden
> SD7H15 is 155cc. It is available with a GM hose fitting. r
>
> The Sanden comes filled with Sanden SP-15 PAG oil. It has a viscosity of
> 80 cSt at 40 deg. C. Sanden says to use only Sanden oil. PAG oil varies in
> viscosity. GM Goodwrench PAG 150 oil comes from Dow just as Sanden does
> and is chemically the same except for viscosity. How important is the
> viscosity issue?
>
> My system has had both R12 and 134 refrigerants and mixed oil. So I will
> need to flush the system. I have read that it is ok to use mineral spirits
> as a flush. I have also read not to use it and to only use a/c flush
> solvent. Opinions welcome.
>
> I know that I have to replace the accumulator and remove the expansion
> valve before flushing but should I replace the expansion valve? With
> everything made in China these days and given some of the experiences that
> I have had with Chinese auto parts, my first thought is to reuse the
> expansion valve. Can it be cleaned effectively? I have no idea what I will
> find when I start flushing. I find references to "Black Death", the
> resulting goo of mixing mineral oil and R12 with PAG or ester oil and 134.
> What is the total oil quantity requirement for our system?
>
> I will be using Duracool.
>
> Thanks to all of you for your help.
>
> Rick
> --
> Rick Williams
> Gladstone, Michigan
> 1978 Eleganza II
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

_______________________________________________
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Re: Sanden vs A6 compressor [message #122344 is a reply to message #122338] Tue, 19 April 2011 12:32 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
Messages: 7111
Registered: November 2004
Location: Dexter, Mo.
Karma: 207
Senior Member
Rick, I believe Ken Henderson can answer every one of your questions. If he does not get on here, send him an email.
Ken is just one of the knowlegable GMCers who shares lots of information with us.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] Sanden vs A6 compressor [message #122397 is a reply to message #122338] Tue, 19 April 2011 18:35 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
Senior Member
Rick,

Most of the answers to your questions are available from www.sanden.com,
where you'll find a service manual and a 5-page document specifically
addressing R-12 to R-134 conversion. I don't think it's mentioned there,
but I have, indeed, been advised to use mineral spirits for flushing. With
your mixed oils, I'd definitely replace the filter/dryer. I probably
wouldn't R&R the expansion valve.

The service manual has tables showing the capacities of their various
compressors. You'll have to determine from the vendor whether the F/D
already contains oil. For information, the A-6's displacement is 12.6 ci,
and the maximum cooling capacity 42,000 BTU.

While I'd like to have a larger one "just in case", the SD-508 I'm using is
more than adequate -- we can't run at maximum under any conditions we've
encountered in the past couple of years. The new dash and HVAC arrangement
do help, but the compressor is fully adequate.

Mounting the Sanden is trivially simple: With the A-6 removed (good luck),
remove, and save for someone else, the rear cast iron A-6 mount. Position
the Sanden with one of its 4 forward radial mounting ears in front of the
lower center hole at the front of the flat steel forward A-6 mount. Through
the two Sanden holes which almost align with those left and right of that
bottom hole, scribe where you need to enlarge the holes. With a rat-tail
file elongate the two A-6 mount holes -- only a tiny bit of filing's
necessary to accomodate 5/16" bolts.

Mount the Sanden to the A--6 flat plate with 3 each 5/16-18 bolts, washers
(the Sanden holes are 3/8"), and self-locking nuts. Check the alignment of
the Sanden pulley with the WP & crankshaft pullies -- it should be OK
without shimming.

To stabilize the rear of the Sanden you'll need to fabricate a brace from
one of its mounting ears to the now-unused double-ended head bolts just
behind it. An approximately 1/8"x3/4"x6" steel bar with two bends is
adequate.

Mount the V-belt, adjust it just like the A-6, evacuate & charge the system
with HC-12A (Duracool), & enjoy!

Ken H.
Americus, GA
'76 X-Birchaven w/Cad500/Howell EFI+ & EBL
www.gmcwipersetc.com



On Tue, Apr 19, 2011 at 1:08 PM, Rick Williams <rickw@mich.com> wrote:

>
>
> I just read Michael's post about what he learned at Patterson so I thought
> I would start a discussion about rebuilding the a/c system. I am curious
> about Ken H's discussion. I know he is using a Sanden clone.
>
> The A6 is a large compressor at 207cc. There are some Sandens that are
> 160cc but there are others that are much smaller. What size have people
> used?
>
> My A6 has a front end leak and a noisy clutch. I would just as soon try a
> new replacement as to spend time and money rebuilding it. The Sanden SD7H15
> is 155cc. It is available with a GM hose fitting.
>
> The Sanden comes filled with Sanden SP-15 PAG oil. It has a viscosity of 80
> cSt at 40 deg. C. Sanden says to use only Sanden oil. PAG oil varies in
> viscosity. GM Goodwrench PAG 150 oil comes from Dow just as Sanden does and
> is chemically the same except for viscosity. How important is the viscosity
> issue?
>
> My system has had both R12 and 134 refrigerants and mixed oil. So I will
> need to flush the system. I have read that it is ok to use mineral spirits
> as a flush. I have also read not to use it and to only use a/c flush
> solvent. Opinions welcome.
>
> I know that I have to replace the accumulator and remove the expansion
> valve before flushing but should I replace the expansion valve? With
> everything made in China these days and given some of the experiences that I
> have had with Chinese auto parts, my first thought is to reuse the expansion
> valve. Can it be cleaned effectively? I have no idea what I will find when I
> start flushing. I find references to "Black Death", the resulting goo of
> mixing mineral oil and R12 with PAG or ester oil and 134. What is the total
> oil quantity requirement for our system?
>
> I will be using Duracool.
>
> Thanks to all of you for your help.
>
> Rick
> --
> Rick Williams
> Gladstone, Michigan
> 1978 Eleganza II
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: Sanden vs A6 compressor [message #122624 is a reply to message #122338] Thu, 21 April 2011 12:01 Go to previous messageGo to next message
tgeiger is currently offline  tgeiger   United States
Messages: 518
Registered: February 2006
Location: kansas city
Karma: -1
Senior Member
Reading this string on the A6, it sounds like it's a monster of a compressor and I should keep it if I could.
I'm having my mechanic look at mine now. I told him that it dosn't seem like the clutch is ingaging. So I asked him to check the restrictor valve to see if it caused the clutch to not ingage. It seems to be holding pressure fine. I took a reading last summer on the system and it read around 30lbs. So I'm hoping things are fine as far as the system being sealed. I do have Duracool to put in it if he happens to get the system working, but I wonder if I should just let it work with the R12 if it turns out to be the restrictor. I guess my question is at what point of repairs do I cut my losses and get the new compressor installed?

Thanks guys,
TG


Tom Geiger 76 Eleganza II KCMO
Re: Sanden vs A6 compressor [message #122628 is a reply to message #122624] Thu, 21 April 2011 12:44 Go to previous message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
If the clutch is not engaging then you are probably low on freon. Unplug the pressure switch on the high side which is located on the passenger side of the air box and short it out with a paperclip. If the clutch engages then you will know it is not a clutch problem and it is time to get out the AC gauges.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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