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dash climate control [message #120708] Sun, 03 April 2011 17:06 Go to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
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Just digging into the issues with my dash controls, and found my climate control unit is broke. the vacuum stuff seems to work fine, but it is the plastic part that allows the levers to move side to side. the pin top to bottum is broke.

is there a repair? and what years of cars would fit? I have access to some suburbans. but they are late 80's.

I see alot about fixing the vacuum wafers, but I do not think that is my problem.


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] dash climate control [message #120710 is a reply to message #120708] Sun, 03 April 2011 17:15 Go to previous messageGo to next message
powerjon is currently offline  powerjon   United States
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Registered: January 2004
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Jon,
You should go to this site on GMCWS:

http://www.gmcws.org/Tech/junkyardgems/index.htm

Download the document and look on page 4.

Don't loose the gmc coach OEM disc.


J.R. Wright
GMC GreatLaker
TZE Zone Restorations
77 Eleganza Custom (Sold Pending Closing)
'78 Transmode Custom (Purchased Pending closing)
1975 Avion (Under Reconstruction)
Michigan

On Apr 3, 2011, at 6:06 PM, Jon Roche wrote:

>
>
> Just digging into the issues with my dash controls, and found my
> climate control unit is broke. the vacuum stuff seems to work fine,
> but it is the plastic part that allows the levers to move side to
> side. the pin top to bottum is broke.
>
> is there a repair? and what years of cars would fit? I have access
> to some suburbans. but they are late 80's.
>
> I see alot about fixing the vacuum wafers, but I do not think that
> is my problem.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

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J.R. Wright
GMC GreatLaker
GMC Eastern States
GMCMI
78 30' Buskirk Stretch
75 Avion Under Reconstruction
Michigan
Re: dash climate control [message #120712 is a reply to message #120708] Sun, 03 April 2011 17:33 Go to previous messageGo to next message
Carl S. is currently offline  Carl S.   United States
Messages: 4186
Registered: January 2009
Location: Tucson, AZ.
Karma: 13
Senior Member

Jon wrote on Sun, 03 April 2011 15:06

Just digging into the issues with my dash controls, and found my climate control unit is broke. the vacuum stuff seems to work fine, but it is the plastic part that allows the levers to move side to side. the pin top to bottum is broke.

is there a repair? and what years of cars would fit? I have access to some suburbans. but they are late 80's.

I see alot about fixing the vacuum wafers, but I do not think that is my problem.


Jon,

I just recently fixed the same problem on my dash HVAC control. The center pivot pin had broken back in November and it took me a while to realize it was even broken. It didn't feel right, but I must have been in denial because I didn't want to face fixing it.

It was really not a big deal. I got the new aluminum pivot pin (that I believe is made by Sirum's) from Jim K, and the installation was relatively easy. You have to remove the dash cover, remove the dash trim bezel, un-plug the wiring and vacuum harnesses, and disconnect a cable from the unit, then it comes out by removing four screws from the front of the dash panel.

The control consists of a series of cams that ride on that pin. You will want to pry the two little knobs off the sliders on the front, and be careful to keep the parts straight so you can re-assemble them in the opposite order that you removed them. I cleaned up the parts and lubricated them with spray white lithium grease and made sure the cable was lubricated also.

It took me a couple of months of thinking about doing it before I finally tackled the job, and probably less than two hours to fix the thing, once I finally got myself to do it. It was really a pretty easy thing to fix.


Carl Stouffer '75 ex Palm Beach Tucson, AZ. Chuck Aulgur Reaction Arm Disc Brakes, Quadrabags, 3.70 LSD final drive, Lenzi knuckles/hubs, Dodge Truck 16" X 8" front wheels, Rear American Eagles, Solar battery charging. GMCSJ and GMCMI member
Re: [GMCnet] dash climate control [message #120717 is a reply to message #120712] Sun, 03 April 2011 18:07 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
On Sun, Apr 3, 2011 at 6:33 PM, Carl Stouffer <carljr3b@yahoo.com> wrote:

>
> ...

The control consists of a series of cams that ride on that pin. You will
> want to pry the two little knobs off the sliders on the front, and be
> careful to keep the parts straight so you can re-assemble them in the
> opposite order that you removed them. I cleaned up the parts and lubricated
> them with spray white lithium grease and made sure the cable was lubricated
> also.
>
>
That's good: "white lithium grease". Just in Case: DON'T use a silicone
grease -- you or a SO (Subsequent Owner) may install EFI; its O2 sensor
won't like the silicone. Something we all need to think about when
introducing silicone into anywhere in the engine or any of its plumbing.

Ken H.
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] dash climate control [message #120737 is a reply to message #120717] Sun, 03 April 2011 21:58 Go to previous messageGo to next message
Larry C   United States
Messages: 1168
Registered: July 2004
Location: NE Illinois by the Illino...
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Senior Member
EFI; its O2 sensor won't like the silicone.
____________________________


Funny you should mention that Ken. After my Summer of scraping all the SILICONE off the body that the PO had used, I'm not so fond of silicone either.... Laughing Can we blame Dan for this????


Huh, huh, huh


Gatsbys' CRUISER 08-18-04
74 GLACIER X, 260/455-APC-4 Bagg'r
Remflex Manifold gaskets
CampGrounds needed, Add yours to "PLACES" /> http://www.gmceast.com/travel
_
Re: dash climate control [message #120743 is a reply to message #120712] Sun, 03 April 2011 23:00 Go to previous messageGo to next message
idrob is currently offline  idrob   United States
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Registered: January 2005
Location: Central Idaho
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Senior Member
Carl S. wrote on Sun, 03 April 2011 15:33

Jon wrote on Sun, 03 April 2011 15:06

Just digging into the issues with my dash controls, and found my climate control unit is broke. the vacuum stuff seems to work fine, but it is the plastic part that allows the levers to move side to side. the pin top to bottum is broke.

is there a repair? and what years of cars would fit? I have access to some suburbans. but they are late 80's.

I see alot about fixing the vacuum wafers, but I do not think that is my problem.


Jon,

I just recently fixed the same problem on my dash HVAC control. The center pivot pin had broken back in November and it took me a while to realize it was even broken. It didn't feel right, but I must have been in denial because I didn't want to face fixing it.

It was really not a big deal. I got the new aluminum pivot pin (that I believe is made by Sirum's) from Jim K, and the installation was relatively easy. You have to remove the dash cover, remove the dash trim bezel, un-plug the wiring and vacuum harnesses, and disconnect a cable from the unit, then it comes out by removing four screws from the front of the dash panel.

The control consists of a series of cams that ride on that pin. You will want to pry the two little knobs off the sliders on the front, and be careful to keep the parts straight so you can re-assemble them in the opposite order that you removed them. I cleaned up the parts and lubricated them with spray white lithium grease and made sure the cable was lubricated also.

It took me a couple of months of thinking about doing it before I finally tackled the job, and probably less than two hours to fix the thing, once I finally got myself to do it. It was really a pretty easy thing to fix.


This is the exact correct response to the problem, the pin is about $10 and it is not all that difficult to put in. In the 70's they thought that Nylon plastic was forever. Turns out it is not. I do sewing machine repairs for a hobby and there are many that have nylon gears or plastic cam parts that have failed and are no longer available. Then they are junk. Fortunately this part is available from our vendors and is made of Alum.

Any used control you might happen to find in a junk yard would have the same age part and the same issue.




Rob Allen
former owner of '76 x-PB
Re: dash climate control [message #120770 is a reply to message #120708] Mon, 04 April 2011 07:46 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
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Senior Member
excellent. I will be on the phone this morning to order up that PIN. that should be exactly the fix.

I have not seen talk of that part anywhere before.


Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] dash climate control [message #120789 is a reply to message #120770] Mon, 04 April 2011 09:21 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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did you read here?
http://www.gmcmotorhome.info/heat.html#CONTROL

gene



On Mon, Apr 4, 2011 at 5:46 AM, Jon Roche <lqqkatjon@gmail.com> wrote:

>
>
> excellent. I will be on the phone this morning to order up that PIN. that
> should be exactly the fix.
>
> I have not seen talk of that part anywhere before.
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>



--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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Re: [GMCnet] dash climate control [message #120792 is a reply to message #120789] Mon, 04 April 2011 09:40 Go to previous message
lqqkatjon is currently offline  lqqkatjon   United States
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Registered: October 2010
Location: St. Cloud, MN
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Senior Member
I did. at first look, it sounded what I was talking about. But the last statement "The pin gets brittle and breaks and then the unit leaks vacuum". Confused me. and sent me looking elsewhere.

the broken pin really is not tied to any vacuum when I look at it. just causes the levers not to move properly, or get to the correct position. so I thought that PIN was some internal to the vacuum switch.





Jon Roche 75 palm beach EBL EFI, manny headers, Micro Level, rebuilt most of coach now. St. Cloud, MN http://lqqkatjon.blogspot.com/
Re: [GMCnet] dash climate control [message #120794 is a reply to message #120789] Mon, 04 April 2011 09:37 Go to previous message
Mr ERFisher is currently offline  Mr ERFisher   United States
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Registered: August 2005
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Senior Member
and did you look here
http://www.gmcmhphotos.com/photos/showphoto.php?photo=16323&cat=4414
or
http://goo.gl/81QUD

gene



On Mon, Apr 4, 2011 at 7:21 AM, Mr.erf ERFisher <mr.erfisher@gmail.com>wrote:

> did you read here?
> http://www.gmcmotorhome.info/heat.html#CONTROL
>
> gene
>
>
>
>
> On Mon, Apr 4, 2011 at 5:46 AM, Jon Roche <lqqkatjon@gmail.com> wrote:
>
>>
>>
>> excellent. I will be on the phone this morning to order up that PIN.
>> that should be exactly the fix.
>>
>> I have not seen talk of that part anywhere before.
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>>
>
>
>
> --
> Gene Fisher -- 74-23,77PB/ore/ca
> “Give a man a fish; you have fed him for today --- give him a URL and
> -------
> http://gmcmotorhome.info/
> Alternator Protection Cable
> http://gmcmotorhome.info/APC.html
>



--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
http://gmcmotorhome.info/
Alternator Protection Cable
http://gmcmotorhome.info/APC.html
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