Home » Public Forums » GMCnet » dash air (dash air)
| dash air [message #304189] |
Mon, 25 July 2016 05:02  |
Glover, Brian K.
Messages: 87
Registered: October 2015
Location: Griffin Georgia
Karma: 0
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Member |
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I bought my motorhome 2 years ago and the dash air has never worked ? I am just now getting into it and would like anyones input on it ? I just now started messing with it so havent got a lot to offer yet !? nothing works ? only thing I have done so far is check the fuse and it is good. I know Im not offering much information yet, but as always know you guys have great insight into anything GMC !
thanks,
Brian
Brian G.
Griffin Ga.
1978 Eleganza II
TZE168V101637
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| Re: dash air [message #304190 is a reply to message #304189] |
Mon, 25 July 2016 05:47  |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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Well, If nothing works, the first thing you need to do is get the fan running. You can troubleshoot the fan even if the compressor is not running.
The next thing to do is see if the compressor is running. Put the system on full cold and the fan on full speed and see if the compressor clutch ever energizes.
If it does not energize you need to decide if it is an electrical problem or a refrigerant charge problem.
Pull the connector off of the pressure switch and short the connector pins with a paper clip. Start the engine with the AC on and see if the clutch energizes.
If it does, REMOVE the Jumper. You do not have an electrical problem.
Now you are down to a refrigerant charge problem. You need to get a gauge and see if there is any refrigerant in the system. If it is low or empty you need to recharge it. I strongly suggest any recharge be done with Duracool. If you get this far and need to recharge, post again and one of us will help you with the recharge.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: [GMCnet] dash air [message #304192 is a reply to message #304190] |
Mon, 25 July 2016 05:54 |
Glover, Brian K.
Messages: 87
Registered: October 2015
Location: Griffin Georgia
Karma: 0
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Member |
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Thanks, Ken
I was thinking of pulling the unit out of the dash to check for power ? because when I say nothing is working I mean nothing ?! no sounds at all no clicking or fans or anything ? I wonder if the dash air unit itself is dead ? and do you think you could pick one up at a junk yard ?
Again, I know I have a lot to look into, but I always like to get yalls input on how to start !
Thanks ,
Brian
-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Ken Burton
Sent: Monday, July 25, 2016 6:48 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] dash air
Well, If nothing works, the first thing you need to do is get the fan running. You can troubleshoot the fan even if the compressor is not running.
The next thing to do is see if the compressor is running. Put the system on full cold and the fan on full speed and see if the compressor clutch ever
energizes.
If it does not energize you need to decide if it is an electrical problem or a refrigerant charge problem.
Pull the connector off of the pressure switch and short the connector pins with a paper clip. Start the engine with the AC on and see if the clutch
energizes.
If it does, REMOVE the Jumper. You do not have an electrical problem.
Now you are down to a refrigerant charge problem. You need to get a gauge and see if there is any refrigerant in the system. If it is low or empty
you need to recharge it. I strongly suggest any recharge be done with Duracool. If you get this far and need to recharge, post again and one of us
will help you with the recharge.
--
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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Brian G.
Griffin Ga.
1978 Eleganza II
TZE168V101637
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| Re: [GMCnet] dash air [message #304194 is a reply to message #304192] |
Mon, 25 July 2016 06:42 |
Ken Henderson
Messages: 8726
Registered: March 2004
Location: Americus, GA
Karma: 9
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Senior Member |
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Brian,
The "other Ken" here 'cause I'm already up.
First off, forget replacing the whole unit from a junk yard -- ain't no
direct replacement. Besides, there's probably nothing major wrong with
yours.
,
Secondly, you need to tell us what year coach it's in -- there are 3
distinctly different HVACs in GMCs.
Thirdly, you need to download and study
http://gmcws.org/Tech/air_conditioning/air_conditing.html, the
authoritative source for upgrading GMC A/C.
Fourthly, Ken B. forgot to mention one thing when he told you to turn the
A/C blower to Hi for your initial test: The engine MUST be running for the
fan to run in Hi -- it's fed directly from the alternator, not the battery,
in that position. In all other speeds, there's a relay involved, which
sometimes fails.
Fifth, follow Ken B.'s instructions first of all.
Ken H.
On Mon, Jul 25, 2016 at 6:54 AM, Glover, Brian K.
wrote:
> Thanks, Ken
>
> I was thinking of pulling the unit out of the dash to check for power ?
> because when I say nothing is working I mean nothing ?! no sounds at all no
> clicking or fans or anything ? I wonder if the dash air unit itself is dead
> ? and do you think you could pick one up at a junk yard ?
>
> Again, I know I have a lot to look into, but I always like to get yalls
> input on how to start !
>
> Thanks ,
>
>
> Brian
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Ken
> Burton
> Sent: Monday, July 25, 2016 6:48 AM
> To: gmclist@list.gmcnet.org
> Subject: Re: [GMCnet] dash air
>
> Well, If nothing works, the first thing you need to do is get the fan
> running. You can troubleshoot the fan even if the compressor is not
> running.
>
> The next thing to do is see if the compressor is running. Put the system
> on full cold and the fan on full speed and see if the compressor clutch ever
> energizes.
>
> If it does not energize you need to decide if it is an electrical problem
> or a refrigerant charge problem.
>
> Pull the connector off of the pressure switch and short the connector pins
> with a paper clip. Start the engine with the AC on and see if the clutch
> energizes.
>
> If it does, REMOVE the Jumper. You do not have an electrical problem.
>
> Now you are down to a refrigerant charge problem. You need to get a gauge
> and see if there is any refrigerant in the system. If it is low or empty
> you need to recharge it. I strongly suggest any recharge be done with
> Duracool. If you get this far and need to recharge, post again and one of
> us
> will help you with the recharge.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> _______________________________________________
> GMCnet mailing list
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
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| Re: [GMCnet] dash air [message #304196 is a reply to message #304194] |
Mon, 25 July 2016 06:55 |
emerystora
Messages: 4442
Registered: January 2004
Karma: 13
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Senior Member |
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Ken
In his first message he says in his signature line that it's a 1978 Eleganza Ii
Emery Stora
> On Jul 25, 2016, at 5:42 AM, Ken Henderson wrote:
>
> Brian,
>
> The "other Ken" here 'cause I'm already up.
>
> First off, forget replacing the whole unit from a junk yard -- ain't no
> direct replacement. Besides, there's probably nothing major wrong with
> yours.
> ,
> Secondly, you need to tell us what year coach it's in -- there are 3
> distinctly different HVACs in GMCs.
>
> Thirdly, you need to download and study
> http://gmcws.org/Tech/air_conditioning/air_conditing.html, the
> authoritative source for upgrading GMC A/C.
>
> Fourthly, Ken B. forgot to mention one thing when he told you to turn the
> A/C blower to Hi for your initial test: The engine MUST be running for the
> fan to run in Hi -- it's fed directly from the alternator, not the battery,
> in that position. In all other speeds, there's a relay involved, which
> sometimes fails.
>
> Fifth, follow Ken B.'s instructions first of all.
>
> Ken H.
>
>
> On Mon, Jul 25, 2016 at 6:54 AM, Glover, Brian K.
> wrote:
>
>> Thanks, Ken
>>
>> I was thinking of pulling the unit out of the dash to check for power ?
>> because when I say nothing is working I mean nothing ?! no sounds at all no
>> clicking or fans or anything ? I wonder if the dash air unit itself is dead
>> ? and do you think you could pick one up at a junk yard ?
>>
>> Again, I know I have a lot to look into, but I always like to get yalls
>> input on how to start !
>>
>> Thanks ,
>>
>>
>> Brian
>>
>> -----Original Message-----
>> From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Ken
>> Burton
>> Sent: Monday, July 25, 2016 6:48 AM
>> To: gmclist@list.gmcnet.org
>> Subject: Re: [GMCnet] dash air
>>
>> Well, If nothing works, the first thing you need to do is get the fan
>> running. You can troubleshoot the fan even if the compressor is not
>> running.
>>
>> The next thing to do is see if the compressor is running. Put the system
>> on full cold and the fan on full speed and see if the compressor clutch ever
>> energizes.
>>
>> If it does not energize you need to decide if it is an electrical problem
>> or a refrigerant charge problem.
>>
>> Pull the connector off of the pressure switch and short the connector pins
>> with a paper clip. Start the engine with the AC on and see if the clutch
>> energizes.
>>
>> If it does, REMOVE the Jumper. You do not have an electrical problem.
>>
>> Now you are down to a refrigerant charge problem. You need to get a gauge
>> and see if there is any refrigerant in the system. If it is low or empty
>> you need to recharge it. I strongly suggest any recharge be done with
>> Duracool. If you get this far and need to recharge, post again and one of
>> us
>> will help you with the recharge.
>> --
>> Ken Burton - N9KB
>> 76 Palm Beach
>> Hebron, Indiana
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> _______________________________________________
> GMCnet mailing list
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| Re: [GMCnet] dash air [message #304200 is a reply to message #304199] |
Mon, 25 July 2016 08:10 |
Glover, Brian K.
Messages: 87
Registered: October 2015
Location: Griffin Georgia
Karma: 0
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Member |
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Rob,
I have a manual printed out X7120A PN. 2028572.
Doesn't really give you any great detail, I will look up the manual you are referencing so I can get a better understanding of operation.
Thanks,
Brian
-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Rob Mueller
Sent: Monday, July 25, 2016 5:28 PM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] dash air
Brian,
I'm going to demonstrate an acute grasp on the obvious and suggest you get a copy of X-7525 and read/study section 1 -
Air-Conditioning. This will give you a good grasp on the basics of the system, that way when "we" make recommendations you won't be
lost.
The good news is that you have a 1978 GMC and they have the best of the worst (so to speak).
Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Glover
I bought my motorhome 2 years ago and the dash air has never worked ? I am just now getting into it and would like anyones input on
it ? I just now started messing with it so havent got a lot to offer yet !? nothing works ? only thing I have done so far is check
the fuse and it is good. I know I'm not offering much information yet, but as always know you guys have great insight into anything
GMC !
thanks,
Brian
_______________________________________________
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Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
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Brian G.
Griffin Ga.
1978 Eleganza II
TZE168V101637
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| Re: [GMCnet] dash air [message #304206 is a reply to message #304200] |
Mon, 25 July 2016 09:01 |
powerjon
Messages: 2446
Registered: January 2004
Karma: 5
|
Senior Member |
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What is the X-7120 manual? I cannot seem to find it on the list of maintenance manuals. The Type 2 air package was the best of all the systems installed in the GMC. The type 2 system in my 77 coach would absolutely frost you out and required a small blanket on the legs. DO NOT start tearing stuff up, do the check to eliminate and find your problems. You have gotten good advice here already. Give us your results and ask more questions. What ever you do, DO NOT put R-134 into your system!
JR
> On Jul 25, 2016, at 9:10 AM, Glover, Brian K. wrote:
>
> Rob,
>
> I have a manual printed out X7120A PN. 2028572.
> Doesn't really give you any great detail, I will look up the manual you are referencing so I can get a better understanding of operation.
>
> Thanks,
> Brian
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Rob Mueller
> Sent: Monday, July 25, 2016 5:28 PM
> To: gmclist@list.gmcnet.org
> Subject: Re: [GMCnet] dash air
>
> Brian,
>
> I'm going to demonstrate an acute grasp on the obvious and suggest you get a copy of X-7525 and read/study section 1 -
> Air-Conditioning. This will give you a good grasp on the basics of the system, that way when "we" make recommendations you won't be
> lost.
>
> The good news is that you have a 1978 GMC and they have the best of the worst (so to speak).
>
> Regards,
> Rob M.
> USAussie - Downunder
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Glover
>
> I bought my motorhome 2 years ago and the dash air has never worked ? I am just now getting into it and would like anyones input on
> it ? I just now started messing with it so havent got a lot to offer yet !? nothing works ? only thing I have done so far is check
> the fuse and it is good. I know I'm not offering much information yet, but as always know you guys have great insight into anything
> GMC !
>
> thanks,
>
> Brian
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J.R. Wright
GMC GreatLaker
GMC Eastern States
GMCMI
78 30' Buskirk Stretch
75 Avion Under Reconstruction
Michigan
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| Re: [GMCnet] dash air [message #304218 is a reply to message #304200] |
Mon, 25 July 2016 11:32 |
jimk
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
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Senior Member |
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When you state that the unit does not work, it does not mean much.
Does the vent fan work?
On Mon, Jul 25, 2016 at 6:10 AM, Glover, Brian K.
wrote:
> Rob,
>
> I have a manual printed out X7120A PN. 2028572.
> Doesn't really give you any great detail, I will look up the manual you
> are referencing so I can get a better understanding of operation.
>
> Thanks,
> Brian
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Rob
> Mueller
> Sent: Monday, July 25, 2016 5:28 PM
> To: gmclist@list.gmcnet.org
> Subject: Re: [GMCnet] dash air
>
> Brian,
>
> I'm going to demonstrate an acute grasp on the obvious and suggest you get
> a copy of X-7525 and read/study section 1 -
> Air-Conditioning. This will give you a good grasp on the basics of the
> system, that way when "we" make recommendations you won't be
> lost.
>
> The good news is that you have a 1978 GMC and they have the best of the
> worst (so to speak).
>
> Regards,
> Rob M.
> USAussie - Downunder
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
>
> -----Original Message-----
> From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Glover
>
> I bought my motorhome 2 years ago and the dash air has never worked ? I am
> just now getting into it and would like anyones input on
> it ? I just now started messing with it so havent got a lot to offer yet
> !? nothing works ? only thing I have done so far is check
> the fuse and it is good. I know I'm not offering much information yet,
> but as always know you guys have great insight into anything
> GMC !
>
> thanks,
>
> Brian
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Fremont,CA
jimk@appliedairfilters.com
http://www.appliedgmc.com
1-800-752-7502
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Jim Kanomata
Applied/GMC
jimk@appliedairfilters.com
www.appliedgmc.com
1-800-752-7502
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| Re: [GMCnet] dash air [message #304220 is a reply to message #304218] |
Mon, 25 July 2016 11:45 |
Glover, Brian K.
Messages: 87
Registered: October 2015
Location: Griffin Georgia
Karma: 0
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Member |
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Nothing works ,, you can move all the controls and there is no noise of any kind or no sign of operation.
Sent from my iPhone
> On Jul 25, 2016, at 12:33 PM, Jim Kanomata wrote:
>
> When you state that the unit does not work, it does not mean much.
> Does the vent fan work?
>
> On Mon, Jul 25, 2016 at 6:10 AM, Glover, Brian K.
> wrote:
>
>> Rob,
>>
>> I have a manual printed out X7120A PN. 2028572.
>> Doesn't really give you any great detail, I will look up the manual you
>> are referencing so I can get a better understanding of operation.
>>
>> Thanks,
>> Brian
>>
>> -----Original Message-----
>> From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Rob
>> Mueller
>> Sent: Monday, July 25, 2016 5:28 PM
>> To: gmclist@list.gmcnet.org
>> Subject: Re: [GMCnet] dash air
>>
>> Brian,
>>
>> I'm going to demonstrate an acute grasp on the obvious and suggest you get
>> a copy of X-7525 and read/study section 1 -
>> Air-Conditioning. This will give you a good grasp on the basics of the
>> system, that way when "we" make recommendations you won't be
>> lost.
>>
>> The good news is that you have a 1978 GMC and they have the best of the
>> worst (so to speak).
>>
>> Regards,
>> Rob M.
>> USAussie - Downunder
>> AUS '75 Avion - The Blue Streak TZE365V100428
>> USA '75 Avion - Double Trouble TZE365V100426
>>
>> -----Original Message-----
>> From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of Glover
>>
>> I bought my motorhome 2 years ago and the dash air has never worked ? I am
>> just now getting into it and would like anyones input on
>> it ? I just now started messing with it so havent got a lot to offer yet
>> !? nothing works ? only thing I have done so far is check
>> the fuse and it is good. I know I'm not offering much information yet,
>> but as always know you guys have great insight into anything
>> GMC !
>>
>> thanks,
>>
>> Brian
>>
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
>
> --
> Jim Kanomata
> Applied/GMC, Fremont,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
Brian G.
Griffin Ga.
1978 Eleganza II
TZE168V101637
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| Re: [GMCnet] dash air [message #304226 is a reply to message #304225] |
Mon, 25 July 2016 12:35 |
Glover, Brian K.
Messages: 87
Registered: October 2015
Location: Griffin Georgia
Karma: 0
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Member |
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Thanks, I will take a look this evening and see if I can come up with something.
Thanks,
-----Original Message-----
From: Gmclist [mailto:gmclist-bounces@list.gmcnet.org] On Behalf Of A.
Sent: Monday, July 25, 2016 1:32 PM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] dash air
Glover, Brian K. wrote on Mon, 25 July 2016 05:02
> I bought my motorhome 2 years ago and the dash air has never worked ? I am just now getting into it and would like anyones input on it ? I just
> now started messing with it so havent got a lot to offer yet !? nothing works ? only thing I have done so far is check the fuse and it is good. I
> know Im not offering much information yet, but as always know you guys have great insight into anything GMC !
>
> thanks,
>
> Brian
It probably has some corroded connections. My Sequoia had a connection out of the blower relay that a PO spliced poorly and once I cleaned and
soldered that, mine blows all speeds. Get the wiring diagram from here and start checking continuity (AC/Heater is at the bottom):
http://www.bdub.net/wirediagrams/78-chassis-electrolevel-II.pdf
Everything outside is on the firewall and the blower box, easy to get to. You might need to carefully remove the dash control to check connections to
it.
--
73 23' Sequoia 4 Sale
73 23' CanyonLands Parts Unit 4 Sale
Upper Alabama
"Highest price does not guarantee highest quality."
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Brian G.
Griffin Ga.
1978 Eleganza II
TZE168V101637
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| Re: dash air [message #304239 is a reply to message #304189] |
Mon, 25 July 2016 18:10 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
|
Senior Member |
|
|
You need to get the fan working First. It is used for both the heater and the AC. Download the wiring diagram as a start. The most common items to fail in the fan circuit are:
1. The fuse (please note: Beside the fuse in the normal fuse panel, there is a separate fuse or fusible link under the hood just for the full speed fan position.
2. The fan motor (available from Auto Zone)
3. The fan relay
4. Burned / bad connections on the fan relay
5. The ground wire on the fan motor which is mounted to the metal containing the fan.
There are other things in the circuit that can fail but the above are the most common things and all are easy to diagnose and replace.
So get out a volt meter and the wiring diagram and start probing.
Colonel Ken mentioned something that is important and I did not mention earlier. When diagnosing the fan circuit, the full speed position requires the engine alternator to be running. You can troubleshoot the other slower speeds with the key on and the engine not running.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: dash air [message #304240 is a reply to message #304239] |
Mon, 25 July 2016 18:42 |
Bullitthead
Messages: 1411
Registered: November 2013
Karma: 5
|
Senior Member |
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Don't forget the blower resistor assembly. The high speed relay AND the resistor were both inoperative on mine when I got it, in addition to the connections on the relay being kinda toasted. The resistor being broken will stop the blower from operating in the slower speeds.
Terry Kelpien
ASE Master Technician
73 Glacier 260
Smithfield, Va.
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| Re: dash air [message #304241 is a reply to message #304239] |
Mon, 25 July 2016 18:44 |
Bullitthead
Messages: 1411
Registered: November 2013
Karma: 5
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Senior Member |
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Don't forget the blower resistor assembly. The high speed relay AND the resistor were both inoperative on mine when I got it, in addition to the connections on the relay being kinda toasted. The resistor being broken will stop the blower from operating in the slower speeds. In addition to that, the fuse box connection sometimes loses continuity due to 40 years of oxidation on the fuse retainer clips.
Terry Kelpien
ASE Master Technician
73 Glacier 260
Smithfield, Va.
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| Re: dash air [message #304253 is a reply to message #304241] |
Tue, 26 July 2016 03:11 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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I intentionally did not list the resistor or the switch. I do not want to overwhelm him with too many possibilities. I figured once we get him in there with a meter or test light we can bring those items into the mix if the readings indicate they could be a problem. I gave him the most common stuff to look at whit his meter.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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| Re: dash air [message #304264 is a reply to message #304189] |
Tue, 26 July 2016 11:45 |
lw8000
Messages: 201
Registered: July 2012
Location: S.E. Michigan
Karma: 1
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Senior Member |
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Just wanted to add that once you get the blower/fan system working, do not scrap the old AC system until it's been checked over. It could just need a simple leak fix and/or recharge. We ended up staying with the old system on R-12 after thinking about upgrading to R-143a but it ended up just needing a leak fix and recharge, and ever since has been working great. The old system, as the guys on here told us, is very good and you get COLD air. Duracool is another solution that seems to also work well without having to upgrade the system.
Chris S. -
77 Kingsley, 3.70 FD, mostly OEM -
S.E. Michigan
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| Re: dash air [message #304305 is a reply to message #304189] |
Tue, 26 July 2016 21:40 |
JohnL455
Messages: 4447
Registered: October 2006
Location: Woodstock, IL
Karma: 12
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Senior Member |
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I would suggest learning automotive HVAC on a junk 1978 GM vehicle. They are all pretty much the same with a given year stamp. They all have the same electrical issues after all these years. They can work like new if you know how to do it. There are electrical systems, simple mechanical systems (temp door cable) a whole system of vacuum operated motors and valve, and the refrigeration system itself. And don't forget a working fan clutch is part of the AC system.
John Lebetski
Woodstock, IL
77 Eleganza II
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| Re: dash air [message #304311 is a reply to message #304305] |
Wed, 27 July 2016 07:08 |
kstockwell
Messages: 367
Registered: May 2016
Location: Putney VT
Karma: 4
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Senior Member |
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Our dash air worked when I got the rig 6 weeks ago but didn't work the last time out.
The PO had it checked and recharged just before bringing it to us (for $300) they found no leaks but had some comment about the system being designed for a different size molecule and it needing recharging. I don't remember on what basis.
Can I get one of those recharging units at Bond auto parts and do this myself?
the blower works fine, it's just not cold air anymore. It seems like the compressor turns on as I can feel the engine running it.
Here's the word from the PO when he just recharged it.
I also had the Dash AC recharged. The compressor, replaced by the prior owner for over $800, was cycling more often than last year and the output was not super cooled. . The shop confirmed that the new version of Freon was low and needed to be augmented. The molecules of the new stuff are smaller than Freon molecules and seep around seals designed in the 70's. The last recharge was 2014. My shop says there is no "leak", but that all old systems that have been converted need to be recharged regularly. $360 later we are ready to rock and roll
kelly
1978 Kingsley
Putney VT
[Updated on: Wed, 27 July 2016 07:16] Report message to a moderator |
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