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Where does the heater temp control cable go through the firewall? [message #254482] Sat, 05 July 2014 22:04 Go to next message
bpimm is currently offline  bpimm   United States
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Our coach didn't have this cable so I got a new one. I have the instrument panel out and I don't see a way to get it through the firewall, no holes big enough to get the mounting tabs through. Anyone have a pic showing how it's routed?

Thanks


Brian & RaeDean 1973 26' #383 Washougal WA
Re: [GMCnet] Where does the heater temp control cable go through the firewall? [message #254486 is a reply to message #254482] Sat, 05 July 2014 23:25 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Brian,

If you look on the left (driver's) side of the HVAC box under the left
hood, you should see a 3/16" or so OD lever with the end sticking out
perpendicular to the box. That's the control lever for the mixing door
inside the box. Immediately behind that, on the side of the box, should be
a clamp for the cable. Immediately behind that, in line with the lever and
the clamp, should a be a 3/8" or so hole in the firewall for the cable to
pass through. The round eye on the cable slips over the end of the lever
before the cable's secured in the clamp, which is adjusted to have the
mixing door closed when the dash lever is in the full Cold position.

That's all from memory; you should check the service manual for exact
procedures.

​HTH,

Ken H.

On Sat, Jul 5, 2014 at 11:04 PM, Brian Pimm wrote:

> Our coach didn't have this cable so I got a new one. I have the instrument
> panel out and I don't see a way to get it through the firewall, no holes
> big enough to get the mounting tabs through. Anyone have a pic showing
> how it's routed?
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: Where does the heater temp control cable go through the firewall? [message #254487 is a reply to message #254482] Sat, 05 July 2014 23:41 Go to previous messageGo to next message
glenn2726 is currently offline  glenn2726   United States
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What Ken said...and he's got really good memory..I just had to repair that cable where it mounts to the inside control panel so yes just look behind where it connects on the under hood air box. The cable is a little long and has to be routed around and straight into where it will connect to the inside panel in order for it to work easily. On that cable there is a twist connector that allows you to adjust the length of the cable so when you have it connected to the inside panel you can twist it to the correct length so the air box is completely closed when in the coldest position..Glenn

Glenn W Topeka, KS 1974 GMC 26 ft. Color:Camel Interior:Canyon Land Side Bath, Rear Sitting Area
Re: Where does the heater temp control cable go through the firewall? [message #254493 is a reply to message #254482] Sun, 06 July 2014 03:42 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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bpimm wrote on Sat, 05 July 2014 22:04
Our coach didn't have this cable so I got a new one. I have the instrument panel out and I don't see a way to get it through the firewall, no holes big enough to get the mounting tabs through. Anyone have a pic showing how it's routed?

Thanks


On my '74 it runs through the same hole as the tubes for the air suspension. With the tubes it's a tight fit. It would have to be worked through from the inside to the outside as the tabs on the inside end will not go through that hole with the tubes in place. Otherwise the descriptions of the clamps and attachment are right on.

I believe mine is as it was delivered but, after 40 years, who knows. I was under the hood quite a bit in that area and never saw the hole KenH referred to. Not to say its not there but if I had seen an unoccupied hole I would have run some of my new wiring through it.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: Where does the heater temp control cable go through the firewall? [message #254504 is a reply to message #254482] Sun, 06 July 2014 09:14 Go to previous messageGo to next message
bpimm is currently offline  bpimm   United States
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Mine is a 73 and I dug all around there yesterday and didn't see the hole Ken H described either, so it must be a 75 and up change. I looked at the hole with the air tubes thought there has to be a better idea than that, that would put some serious bends in the cable. I'll go out and double check for the hole and maybe I'll add it if the area is clear on the inside.

Ken does it have a grommet of some kind? with the size of the mounting tab it will take a fairly large hole.



Brian & RaeDean 1973 26' #383 Washougal WA
Re: Where does the heater temp control cable go through the firewall? [message #254505 is a reply to message #254482] Sun, 06 July 2014 09:14 Go to previous messageGo to next message
glenn2726 is currently offline  glenn2726   United States
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Hey Steve, you're right about the holes..lol..I didn't pay that much attention to the holes but do know that cable runs out next to the airbox on the door lever control side. Shouldn't be too hard to find it. And yes it will have to be fed from the inside out due to the cable adjuster and cable attachment for the inside control panel. Glenn

Glenn W Topeka, KS 1974 GMC 26 ft. Color:Camel Interior:Canyon Land Side Bath, Rear Sitting Area
Re: Where does the heater temp control cable go through the firewall? [message #254506 is a reply to message #254482] Sun, 06 July 2014 09:20 Go to previous messageGo to next message
glenn2726 is currently offline  glenn2726   United States
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Yes that cable has some circling to do due to the location...look down behind where the air controls are on your dash, that's where it exits and then you have to bend it around and feed it into your dash controls without kinking it. Glenn

Glenn W Topeka, KS 1974 GMC 26 ft. Color:Camel Interior:Canyon Land Side Bath, Rear Sitting Area
Re: [GMCnet] Where does the heater temp control cable go through the firewall? [message #254508 is a reply to message #254504] Sun, 06 July 2014 09:20 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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Brian,

On my '76, the grommet, if it ever existed (as I'd expect), it was gone by
'98 when I got it. The hole was (now covered) only large enough for
the loop on the forward end to pass.

Ken H.

On Sun, Jul 6, 2014 at 10:14 AM, Brian Pimm wrote:

> ​...​
>
> Ken does it have a grommet of some kind? with the size of the mounting
> tab it will take a fairly large hole.
>
>
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www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: Where does the heater temp control cable go through the firewall? [message #254510 is a reply to message #254506] Sun, 06 July 2014 09:37 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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I'm thinking that the mounting tab or clamp that you are describing is removable from the end of the cable. If it is, remove it, shove the cable through the hole, and reinstall the tab after you have the cable installed on the blend door lever.

Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: Where does the heater temp control cable go through the firewall? [message #254511 is a reply to message #254482] Sun, 06 July 2014 09:46 Go to previous messageGo to next message
bpimm is currently offline  bpimm   United States
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ok, My replacement cable form Jim K has plastic mounting tabs on both ends that measure 1" across. I may be able to get it through the hole for the air lines if they were all removed but it doesn't look like it's 1" across, it has a grommet and the hole in the grommet looks to be 3/4" maybe a bit under. Maybe a new hole is the way to go.

Can the passenger side dash pad be removed or is it an integral part of the dash?
Can the dash be removed without taking out the windshield? screw angle suggests it was installed before the windshield.


Brian & RaeDean 1973 26' #383 Washougal WA
Re: Where does the heater temp control cable go through the firewall? [message #254513 is a reply to message #254482] Sun, 06 July 2014 10:03 Go to previous messageGo to next message
bpimm is currently offline  bpimm   United States
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Both ends are molded on plastic.

http://i101.photobucket.com/albums/m57/bdpimm/20140706_074946.jpg


Brian & RaeDean 1973 26' #383 Washougal WA
Re: [GMCnet] Where does the heater temp control cable go through the firewall? [message #254516 is a reply to message #254511] Sun, 06 July 2014 10:10 Go to previous messageGo to next message
Ken Henderson is currently offline  Ken Henderson   United States
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DON'T remove the dash!!! Not unless you want to build a complete new one:
http://www.gmcmhphotos.com/photos/g4899-new-dash-panel.html

The plastic of the dash has long since lost most of the plasticizers which
made it flexible and resistant to abuse. Many of its features will snap
off during handling and be essentially irreplaceable.

While Frank Jenkins offers a fiberglass replacement, its installation and
adaptation is a task no one with as little GMC ownership experience as you
have should attempt -- it's too likely to exhaust your reserves of energy
and enthusiasm.

JMHO,

Ken H.


On Sun, Jul 6, 2014 at 10:46 AM, Brian Pimm wrote:

> ​...
>

Can the dash be removed without taking out the windshield? screw angle
> suggests it was installed before the windshield.
> --
>
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Ken Henderson
Americus, GA
www.gmcwipersetc.com
Large Wiring Diagrams
76 X-Birchaven
76 X-Palm Beach
Re: [GMCnet] Where does the heater temp control cable go through the firewall? [message #254519 is a reply to message #254516] Sun, 06 July 2014 11:01 Go to previous messageGo to next message
bpimm is currently offline  bpimm   United States
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Ken Henderson wrote on Sun, 06 July 2014 08:10
DON'T remove the dash!!! Not unless you want to build a complete new one:
http://www.gmcmhphotos.com/photos/g4899-new-dash-panel.html

The plastic of the dash has long since lost most of the plasticizers which
made it flexible and resistant to abuse. Many of its features will snap
off during handling and be essentially irreplaceable.

While Frank Jenkins offers a fiberglass replacement, its installation and
adaptation is a task no one with as little GMC ownership experience as you
have should attempt -- it's too likely to exhaust your reserves of energy
and enthusiasm.

JMHO,

Ken H.



HEHEHEHE...

Agreed I don't want to remove the dash "yet", on this coach the plasticizers left a long time ago.. It is basically just sitting there with a few attachment points still attached. It will get replaced at some point haven't decided weather to build a new one or go with the replacement, but that's a few years away yet.
I was hoping the pad on the passenger side could come off for better access but your pics showed otherwise. Nice dash project by the way.

This coach, over the next few years will be a stem to stearn rebuild, hoping to keep it a rolling rebuild so we can use a few times each year with the major projects happening in the winters.

Thanks


Brian & RaeDean 1973 26' #383 Washougal WA
Re: Where does the heater temp control cable go through the firewall? [message #254524 is a reply to message #254513] Sun, 06 July 2014 12:05 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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bpimm wrote on Sun, 06 July 2014 10:03
Both ends are molded on plastic.

http://i101.photobucket.com/albums/m57/bdpimm/20140706_074946.jpg


I would call JimK and talk to Nick. If they are selling them then they know how to get them installed.

If it was me and JimK did not have a method that is worked for me I would determine which end had to be inside and carefully trim off the tab on the other end and work it through the hole. It would be easy with the air tubes out but messing with that system is not advised if it currently works properly. It will be difficult to get that control cable through the hole from the inside. I would push a pull wire back through the hole from the outside and then pull the control cable through the hole.

If you decide to drill a new hole be VERY CAREFUL as the main wiring harness is in this vicinity.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: Where does the heater temp control cable go through the firewall? [message #254533 is a reply to message #254482] Sun, 06 July 2014 13:18 Go to previous messageGo to next message
bpimm is currently offline  bpimm   United States
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Cables in, I drilled a small pilot hole from the outside where I wanted the cable to go through and used a 1/8" end mill in a die grinder to shape a keyhole for the cable mount tab to go through. A bit of caulk and it will be good until it needs a new replacement.

From inside
http://i101.photobucket.com/albums/m57/bdpimm/20140706_103138.jpg


from under the hood
http://i101.photobucket.com/albums/m57/bdpimm/20140706_103103.jpg


Cable installed
http://i101.photobucket.com/albums/m57/bdpimm/20140706_105203.jpg


Cutter
http://i101.photobucket.com/albums/m57/bdpimm/20140706_103154.jpg


Now I need to get a bunch of light bulbs and replace all the bulbs before I put the dash back together.

Thanks


Brian & RaeDean 1973 26' #383 Washougal WA

[Updated on: Sun, 06 July 2014 16:57]

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Re: [GMCnet] Where does the heater temp control cable go through the firewall? [message #254537 is a reply to message #254533] Sun, 06 July 2014 15:11 Go to previous messageGo to next message
powerjon is currently offline  powerjon   United States
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Brian,
Be aware that any picture that you post in a phorm message does not make it to the GMCnet. If you want to be binetual then you need to add the link to your pictures with your phorm message. A large number of netter do not use the phorm. If you want to reach a larger part of the group.
JR Wright
78 Buskirk Stretch
75 Avion
Michigan

On Jul 6, 2014, at 2:18 PM, Brian Pimm wrote:

> Cables in, I drilled a small pilot hole from the outside where I wanted the cable to go through and used a 1/8" end mill in a die grinder to shape a
> keyhole for the cable mount tab to go through. A bit of caulk and it will be good until it needs a new replacement.
>
> From inside
>
>
> from under the hood
>
>
> Cable installed
>
>
> Cutter
>
>
> Now I need to get a bunch of light bulbs and replace all the bulbs before I put the dash back together.
>
> Thanks
>
> --
> Brian & RaeDean
>
> 1973 26' #383
>
> Washougal WA
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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J.R. Wright
GMC GreatLaker
GMC Eastern States
GMCMI
78 30' Buskirk Stretch
75 Avion Under Reconstruction
Michigan
Re: [GMCnet] Where does the heater temp control cable go through the firewall? [message #254544 is a reply to message #254537] Sun, 06 July 2014 17:00 Go to previous messageGo to next message
bpimm is currently offline  bpimm   United States
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powerjon wrote on Sun, 06 July 2014 13:11
Brian,
Be aware that any picture that you post in a phorm message does not make it to the GMCnet. If you want to be binetual then you need to add the link to your pictures with your phorm message. A large number of netter do not use the phorm. If you want to reach a larger part of the group.
JR Wright
78 Buskirk Stretch
75 Avion
Michigan


I've never used a email list before so i have no idea how they work. I reread the pic posting sticky and edited the last post, hopefully I got it right. Can someone let me know if the links came across in the mail list??

Thanks


Brian & RaeDean 1973 26' #383 Washougal WA
Re: [GMCnet] Where does the heater temp control cable go through the firewall? [message #254550 is a reply to message #254544] Sun, 06 July 2014 18:48 Go to previous messageGo to next message
midlf is currently offline  midlf   United States
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bpimm wrote on Sun, 06 July 2014 17:00


I've never used a email list before so i have no idea how they work. I reread the pic posting sticky and edited the last post, hopefully I got it right. Can someone let me know if the links came across in the mail list??

Thanks


You also need to be aware that the emailers do not get a revised forum posting. The original forum post is the only one they see.


Steve Southworth
1974 Glacier TZE064V100150 (for workin on)
1975 Transmode TZE365V100394 (parts & spares)
Palmyra WI
Re: Where does the heater temp control cable go through the firewall? [message #254587 is a reply to message #254533] Mon, 07 July 2014 02:52 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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The email program is a very simple mail forwarder. It does not do what one would expect on a normal forum. One of it's many shortcomings is it can not display pictures. So to accommodate those users who will not come into the 21st century we embed a text line with the actual URL besides the actual image tag (picture) you already did Emailers can then manually go look at the pictures on their own should they wish to see them.

Now comes the rub. If you modify a posting, the forum does not send the modification out to the email server. So emailers never see edits or updates.

The way to get around this is to modify the original posting as you say you have done. Then start another post (or reply) and quote the original (modified) posting as I am doing here. If your modification is correct, they should be able to manually go see those postings while everyone else just see a duplicate posting.

Let see if this works for them now.

bpimm wrote on Sun, 06 July 2014 13:18
Cables in, I drilled a small pilot hole from the outside where I wanted the cable to go through and used a 1/8" end mill in a die grinder to shape a keyhole for the cable mount tab to go through. A bit of caulk and it will be good until it needs a new replacement.

From inside
http://i101.photobucket.com/albums/m57/bdpimm/20140706_103138.jpg


from under the hood
http://i101.photobucket.com/albums/m57/bdpimm/20140706_103103.jpg


Cable installed
http://i101.photobucket.com/albums/m57/bdpimm/20140706_105203.jpg


Cutter
http://i101.photobucket.com/albums/m57/bdpimm/20140706_103154.jpg


Now I need to get a bunch of light bulbs and replace all the bulbs before I put the dash back together.

Thanks



Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
[GMCnet] Forum vs Mail (was: Where does the heater temp control cable go through the firewall?) [message #254591 is a reply to message #254587] Mon, 07 July 2014 05:20 Go to previous messageGo to previous message
Olly Schmidt is currently offline  Olly Schmidt   United States
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Ken,
> [..]So to accommodate those users who will not come into the 21st century[..]

somehow I do feel way better in the 21st century with an email program,
which allows me to get all my messages while being on wifi, and read it
offline, and respond to them while offline and waiting to come back
online, than to need to waste a lot of bandwidth and online time by
using a forum.

Some prefer forums, some prefer mail. Both have advantages, but neither
is more 21st century than the other. My 0.02EUR. :)

I love, what the administrators have done with combining forum and mail
users into one system. The little problems with modifications not going
through etc is something everybody can live with.

--
Best regards

Peer Oliver Schmidt
PGP Key ID: 0x83E1C2EA

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Olly Schmidt
PGP Key ID: 0x18a9 3a1f 4196 bf22
'76a Eleganza II, VA
'73 Sequoia, SH, Germany
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