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[GMCnet] dash air [message #216785] Sat, 03 August 2013 12:57 Go to next message
Kathy and Fred Estabr is currently offline  Kathy and Fred Estabr   United States
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Registered: May 2013
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Is it worth the effort to change the dash air from 76 Type II to 77 Type
III ? I have made the Zay Brand suggested mods to the 76 and still don't
get enough cold air. Has anyone made this change and what is involved.
Fred Estabrook
76 Ell and 77 King ( casita )
Florence AZ
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Re: [GMCnet] dash air [message #216787 is a reply to message #216785] Sat, 03 August 2013 13:04 Go to previous messageGo to next message
ljdavick is currently offline  ljdavick   United States
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Although I have not done Zay's mod to my '76 I did recharge the system with Duracool and cold air comes out if that silly snorkel. It's nowhere near enough to cool the whole coach, but if I have the divider curtain drawn the cockpit stays cool.

Larry Davick

On Aug 3, 2013, at 10:57 AM, Kathy and Fred Estabrook <feektg@gmail.com> wrote:

> Is it worth the effort to change the dash air from 76 Type II to 77 Type
> III ? I have made the Zay Brand suggested mods to the 76 and still don't
> get enough cold air. Has anyone made this change and what is involved.
> Fred Estabrook
> 76 Ell and 77 King ( casita )
> Florence AZ
>
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Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
Re: [GMCnet] dash air [message #216788 is a reply to message #216785] Sat, 03 August 2013 13:08 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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If have never heard of the 77/78 system being referred to as a Type III.

You won't get much benefit of changing everything and it would be a huge amount of work and expense to do so.

Things you can do are to cover the outside air intake on the front and top of the heater box to prevent drawing in any outside air.
I have done this on my 77 and also propped open the max air recirculation vent at the floor so that there is always 100% recirculation

Emery Stora

On Aug 3, 2013, at 11:57 AM, Kathy and Fred Estabrook wrote:

> Is it worth the effort to change the dash air from 76 Type II to 77 Type
> III ? I have made the Zay Brand suggested mods to the 76 and still don't
> get enough cold air. Has anyone made this change and what is involved.
> Fred Estabrook
> 76 Ell and 77 King ( casita )
> Florence AZ
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist

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Re: [GMCnet] dash air [message #216830 is a reply to message #216785] Sat, 03 August 2013 19:49 Go to previous messageGo to next message
JohnL455 is currently offline  JohnL455   United States
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Location: Woodstock, IL
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Since you have a 76 and 77 in your signature I would think you could evaluate the difference. To find all the donor parts would be quite a task for minimum gains.

John Lebetski
Woodstock, IL
77 Eleganza II
Re: [GMCnet] dash air [message #304195 is a reply to message #216785] Mon, 25 July 2016 06:48 Go to previous messageGo to next message
Glover, Brian K. is currently offline  Glover, Brian K.   United States
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Registered: October 2015
Location: Griffin Georgia
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Thanks other Ken !

1978 Eleganza II

I will look through the info you've provided.

Thanks
Ken

Sent from my iPhone

> On Jul 25, 2016, at 7:44 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
>>
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Brian G. Griffin Ga. 1978 Eleganza II TZE168V101637
Re: [GMCnet] dash air [message #304198 is a reply to message #216785] Mon, 25 July 2016 07:16 Go to previous messageGo to next message
lqqkatjon is currently offline  lqqkatjon   United States
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changing to a later model air, seems like a waste of time and energy. from all the years reading, the best thing to do, is add a vintage air or other aux evaporator system, probably way easier then trying to change out the whole system.

It has been years since i messed with my dash A/C, but I remember alot of talk of the 40 year old condensor being caked with junk that will not allow much air to blow through. I think that is where I stopped last time, had it all hotwired, running and blowing cold, just no airflow. My plan is to fix that, but if I am digging into that much work, I am going to add an aux evaporator.



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 air [message #304217 is a reply to message #304198] Mon, 25 July 2016 11:37 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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lqqkatjon wrote on Mon, 25 July 2016 07:16
...add a vintage air or other aux evaporator system, probably way easier then trying to change out the whole system. ...had it all hotwired, running and blowing cold, just no airflow. ...
That lack of airflow could be a condenser full of mouse nest, or it could be the temperature door is not moving, or it could be the system's poor design.

You should really take the front cover off and look at what the actuators are doing and see if the evaporator is plugged up before you start installing things.
Re: [GMCnet] dash air [message #304219 is a reply to message #304217] Mon, 25 July 2016 11:47 Go to previous messageGo to next message
Glover, Brian K. is currently offline  Glover, Brian K.   United States
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Location: Griffin Georgia
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I have no plans yet of installing or removing anything yet, I will follow the recommendations given and see if I can determine a bad part before I go any further.

Thanks

Sent from my iPhone

> On Jul 25, 2016, at 12:39 PM, A. wrote:
>
> lqqkatjon wrote on Mon, 25 July 2016 07:16
>> ...add a vintage air or other aux evaporator system, probably way easier then trying to change out the whole system. ...had it all hotwired,
>> running and blowing cold, just no airflow. ...
> That lack of airflow could be a condenser full of mouse nest, or it could be the temperature door is not moving, or it could be the system's poor
> design.
>
> You should really take the front cover off and look at what the actuators are doing and see if the evaporator is plugged up before you start
> installing things.
> --
> 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
Re: [GMCnet] dash air [message #304223 is a reply to message #304217] Mon, 25 July 2016 12:00 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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G'day,

I have sent Brian all the information he needs to troubleshoot this problem in a logical orderly manner so put away your shotguns.

Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426




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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] dash air [message #304227 is a reply to message #304223] Mon, 25 July 2016 12:55 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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USAussie wrote on Mon, 25 July 2016 12:00
G'day,
I have sent Brian all the information he needs to troubleshoot this problem in a logical orderly manner so put away your shotguns.

Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
I can turn it into a PDF and post it to the photosite if you can send it to me. After that, next time this comes up, we can just post the URL. Shouldn't need to send it out over and over again.
Re: [GMCnet] dash air [message #304228 is a reply to message #304227] Mon, 25 July 2016 13:05 Go to previous messageGo to next message
SteveW is currently offline  SteveW   United States
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Thank you !!

I was just about to ask Rob to send it to me too...

Steve W
1973 23'
Southern California



Steve W 1973 : 23' Southern California
Re: [GMCnet] dash air [message #304229 is a reply to message #304219] Mon, 25 July 2016 14:15 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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Glover, Brian K. wrote on Mon, 25 July 2016 11:47
I have no plans yet of installing or removing anything yet, I will follow the recommendations given and see if I can determine a bad part before I go any further.
Thanks
Brian,

Please forward Rob M's info to me in case he is off list/net for the day.

Thanks.

[Updated on: Mon, 25 July 2016 14:16]

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Re: [GMCnet] dash air [message #304243 is a reply to message #304227] Mon, 25 July 2016 19:20 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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I sent him the manuals.

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 A.
Sent: Tuesday, July 26, 2016 3:56 AM
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] dash air

USAussie wrote on Mon, 25 July 2016 12:00
> G'day,
> I have sent Brian all the information he needs to troubleshoot this problem in a logical orderly manner so put away your shotguns.
>
> Regards,
> Rob M.
> USAussie - Downunder
> AUS '75 Avion - The Blue Streak TZE365V100428
> USA '75 Avion - Double Trouble TZE365V100426
I can turn it into a PDF and post it to the photosite if you can send it to me. After that, next time this comes up, we can just
post the URL.
Shouldn't need to send it out over and over again.
--
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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Regards, Rob M. (USAussie) The Pedantic Mechanic Sydney, Australia '75 Avion - AUS - The Blue Streak TZE365V100428 '75 Avion - USA - Double Trouble TZE365V100426
Re: [GMCnet] dash air [message #304245 is a reply to message #304243] Mon, 25 July 2016 19:48 Go to previous messageGo to next message
A Hamilto is currently offline  A Hamilto   United States
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USAussie wrote on Mon, 25 July 2016 19:20
I sent him the manuals.
Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426
Yes. The flowchart is in the manual. I would have just posted the URLs from which to download (like I did for the wiring diagram).
Re: [GMCnet] dash air [message #304254 is a reply to message #304243] Tue, 26 July 2016 03:14 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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USAussie wrote on Mon, 25 July 2016 19:20
I sent him the manuals.

Regards,
Rob M.
USAussie - Downunder
AUS '75 Avion - The Blue Streak TZE365V100428
USA '75 Avion - Double Trouble TZE365V100426


You are a nice guy.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] dash air [message #304275 is a reply to message #216785] Tue, 26 July 2016 13:08 Go to previous message
Adrien G. is currently offline  Adrien G.   United States
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Location: Burns Flat, OK 73624
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Senior Member
"Not enough cold air."

The diff in dash air distribution (outlets) between 76 & 77 is a lot. I don't know if it could be done without a dash change

In my coach rebuild, I took the dash out and AC box out to repair /recondition. This is what I learned and did.
The AC evaporator (not really large enough can be improved), it can be cleaned. Remove front cover, fan and fan air duct, blower speed resistor asm (on driver side of box) ( see MM X7525 sec 1 page 69, fig 37), blow air from front of evap. If needed the evap can be pulled out of the box.

The foam/ felt for the diverter door need replacing. Insulate the inside of the box (thin glue back foam, or custom cut foam poster board from Walmart or ?).

There's a foam seal (or was 40 years ago) between the AC box outlet and firewall, don't know how assessable it's by removing the heater core. The box unit has 4 mounting bolts, 2 vertical, 2 from inside (1 near fuse box, the other by removing radio).

The air distribution duct, under dash, also has a foam seal at the AC box outlet and firewall. And the duct (2 piece snap together also has air leaks, and it can use some insulation from the sun dash heat. Unfortunately dash removal is required for this. A good thick dash cover can help.

Preventing hot outside air from entering the AC box, manual shut off for heater core hose, and any body air infiltration can help. Cockpit ceiling insulation, tinting of windows. There's no one thing that makes a great change in the AC unit , but a series of accumulative small steps that makes the great change.

My unit could be better, it's still not as cold as I would like it to be, non are. But now it's comfortable, nest step an aux evap ? under couch or ?.

My one small bit of help.





Adrien & Jenny Genesoto 75 Glenbrook (26-3) Mods LS3.70 FD / Reaction Sys / 80mm Front&Intermidiate / Hydroboost / 16" Tires / Frame Rebuild / Interior Rebuild Yuba City,Ca. Text 530-nine-3-three-3-nine-nine-6
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