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Re: [GMCnet] Required air pressure for quad bag rear suspension [message #328920 is a reply to message #328916] Wed, 07 February 2018 09:50 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
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Registered: November 2009
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Senior Member
IIRC, that rollover was a result of operator error by truck driver.

D C "Mac" Macdonald
Amateur Radio K2GKK
Since 30 November '53
USAF and FAA, Retired
Member GMCMI & Classics
Oklahoma City, OK
"The Money Pit"
TZE166V101966
'76 ex-Palm Beach
k2gkk + hotmail dot com



________________________________
From: Gmclist on behalf of Larry
Sent: Wednesday, February 7, 2018 08:10
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Required air pressure for quad bag rear suspension

RF_Burns wrote on Wed, 07 February 2018 05:58
> Finding a tilt-on flat bed that can handle s 23ft should not be hard to find. Ours was a 26ft so the bikerack had to come off and wrap the front
> bumper with HD moving blankets to protect it.
>
> The pot holes on the 401 at this time of the year will be brutal in places, especially through Toronto. Fixing a bent bogie etc ain't that cheap
> either.
>
> I'd pay extra for the roll-on.
>
> Are you going to Borrmann's?

I'd be careful of some of the roll-on trucks. IIRC there is at lease one example of a GMC loaded on a roll-on that was to small for the job and ended
up rolling over destroying both the couch and the truck. choose carefully.
--
Larry
78 Royale w/500 Caddy
Menomonie, WI

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Re: [GMCnet] Required air pressure for quad bag rear suspension [message #328922 is a reply to message #328920] Wed, 07 February 2018 10:16 Go to previous messageGo to next message
Larry is currently offline  Larry   United States
Messages: 2875
Registered: January 2004
Location: Menomonie, WI
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Senior Member
Operator error in that the GMC should never have been put on a roll-back that is that small. Use common sense. If it doesn't look right, don't allow it to happen. JMHO

Larry Smile
78 Royale w/500 Caddy
Menomonie, WI.
Re: [GMCnet] Required air pressure for quad bag rear suspension [message #328927 is a reply to message #328922] Wed, 07 February 2018 12:16 Go to previous messageGo to next message
johnd01 is currently offline  johnd01   United States
Messages: 354
Registered: July 2017
Location: Sacrameot
Karma: -1
Senior Member
What about using the onboard compressor powered by the house batteries or
from 12 volts from the tow truck?

On Wed, Feb 7, 2018 at 8:16 AM, Larry wrote:

> Operator error in that the GMC should never have been put on a roll-back
> that is that small. Use common sense. If it doesn't look right, don't allow
> it to happen. JMHO
> --
> Larry
> 78 Royale w/500 Caddy
> Menomonie, WI.
>
> _______________________________________________
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> Unsubscribe or Change List Options:
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--

*John Phillips*
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Johnd01 John Phillips Avion A2600 TZE064V101164 Rancho Cordova, CA (Sacramento)
Re: [GMCnet] Required air pressure for quad bag rear suspension [message #328929 is a reply to message #328927] Wed, 07 February 2018 13:08 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
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You guys are going through a lot of unnecessary scenarios. Do what Jim K. suggested. Air it up 2 or 3 in inches and turn off the valve. Let it set overnight and see if it goes down. If it does leak, fix the air leak somewhere at the bags. It should hold air for months. Mine has been holding air since last September WITHOUT shut off valves.

You are trying too get it to hold air for a day. All of this other stuff you are suggesting is totally unnecessary. Fix the leak somewhere between the shutoff valve and the bags or the bags themselves if necessary.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana

[Updated on: Wed, 07 February 2018 15:23]

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Re: [GMCnet] Required air pressure for quad bag rear suspension [message #328930 is a reply to message #328929] Wed, 07 February 2018 14:06 Go to previous messageGo to next message
emerystora is currently offline  emerystora   United States
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Registered: January 2004
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Senior Member
I agree with Ken. I’ve had mine towed three times with the front lifted. 350 miles once and 200-250 miles the other two times. All times I pumped the airbags to maximum height and shut off the valves to the air bags. No damages at any time.

Emery Stora
77 Kingsley
Frederick, CO


> On Feb 7, 2018, at 12:08 PM, Ken Burton wrote:
>
> You guys are going through a lot of unnecessary scenarios. Do what Jim K. suggested. Air it up 2 or 3 in inches and turn off the valve. Let it set
> overnight and see if it goes down. If it does leak, fix the air leak somewhere at the bags. It should hold air for months. Mine has been holding
> air since last September WITHOUT shut off valves.
>
> You are trying too get it to hold air for a day. All of this other stuff you are suggesting is totally unnecessary. Fix the leak somewhere at the
> bags.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
> _______________________________________________
> GMCnet mailing list
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Re: Required air pressure for quad bag rear suspension [message #329184 is a reply to message #328867] Thu, 15 February 2018 19:28 Go to previous messageGo to next message
gibsongo is currently offline  gibsongo   Canada
Messages: 116
Registered: October 2012
Location: Montreal West, Quebec, Ca...
Karma: 0
Senior Member
Hello all,

Thanks for all the answers - but it turned out that we went the flatbed route rather than "the hook". I pumped the rear end up as high as possible then shut off the quad bags using the valves incorporated into the system. Luckily it was a bit warmer (-18) and the rear end was only down a but 12 hours later upon arriving at Borrmann's garage. Had it been the -25 we'd had in early January the rear would have been most if not all the way down and we might have had some difficulty getting yhe coach off the flatbed without damaging the tail pipe.

But I guess I still don't understand why (if we'd gone the hook route) 100 psi supplied to the air reservoir by a tow truck would be any different from 100 psi coming from my Viair pump....


Gordon Gibson 1976 23" Norris Upfit Montreal West, Quebec, Canada
Re: Required air pressure for quad bag rear suspension [message #329194 is a reply to message #329184] Thu, 15 February 2018 23:02 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
I guess that I do not understand your concern with air pressure vs. temperature change. The rule has always been a 10 degree F. temperature change = 1 PSI. In your example -18c to -25c is 7c degree temp change. Or around 12F or 13F.

So even if the temperature changed you should not have seen more than 1 or 2 PSI difference in the bags. I did all of the numbers in my head so they are not accurate to .1 degree but they are close enough for academic discussion.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Required air pressure for quad bag rear suspension [message #329207 is a reply to message #329194] Fri, 16 February 2018 12:03 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
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Location: Belmont, CA
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Senior Member
I agree with Ken, sort of misinformation to send out.

On Thu, Feb 15, 2018 at 9:02 PM, Ken Burton wrote:

> I guess that I do not understand your concern with air pressure vs.
> temperature change. The rule has always been a 10 degree F. temperature
> change =
> 1 PSI. In your example -18c to -25c is 7c degree temp change. Or around
> 12F or 13F.
>
> So even if the temperature changed you should not have seen more than 1 or
> 2 PSI difference in the bags. I did all of the numbers in my head so they
> are not accurate to .1 degree but they are close enough for academic
> discussion.
> --
> Ken Burton - N9KB
> 76 Palm Beach
> Hebron, Indiana
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>



--
Jim Kanomata
Applied/GMC, Newark,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
Re: Required air pressure for quad bag rear suspension [message #329220 is a reply to message #328867] Fri, 16 February 2018 20:48 Go to previous messageGo to next message
gibsongo is currently offline  gibsongo   Canada
Messages: 116
Registered: October 2012
Location: Montreal West, Quebec, Ca...
Karma: 0
Senior Member
No misinformation intended...and none conveyed if you take the time to read all the string carefully. New quad bag system, new Viair pump, all new tubing and fittings, new JR Slayton control valves - all installed 12 months ago by an experienced GMC mechanic. The system will hold air for weeks most of the year, but in very cold weather (-20C and colder), it just doesn't. Your experience may differ, but I am relating what happened out in the driveway 5 or 6 times in a cold by historic records late December and January when I would start the engine and get the rear end up to the proper travel level. Now of course, the air could be leaking from any number of fittings, but the "spray soapy water" diagnostic just won't work - the water would freeze long before any bubbles appeared. My bet is on the bags. The fact that the coach lost air over the 12 hours it spent on the flatbed with the shutoff valves closed at the rear suspension manifold (as recommended by several on this forum) tends to substantiate this conclusion.

Gordon Gibson 1976 23" Norris Upfit Montreal West, Quebec, Canada
Re: Required air pressure for quad bag rear suspension [message #329225 is a reply to message #329220] Sat, 17 February 2018 05:02 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
OK Gordon. I was not picking on you. I just did not understand why all the concern over a 7 C temperature change.

You have an interesting problem there. It only leaks when cold below freezing. I have no ideas on the cause for that. I agree that if it leaked when the valves are shut off, that it is probably a bag leak but I also have never worked on a 4 bag system so I do not understand the plumbing involved.

On the soapy water idea, How about using some windshield solvent and soap mixed together? I have never tried that. Maybe that mix will not bubble.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: [GMCnet] Required air pressure for quad bag rear suspension [message #329230 is a reply to message #329225] Sat, 17 February 2018 10:38 Go to previous messageGo to next message
Tangerine is currently offline  Tangerine   United States
Messages: 192
Registered: February 2004
Location: Livonia, MI
Karma: 0
Senior Member
On 2/17/2018 6:02 AM, Ken Burton wrote:
> OK Gordon. I was not picking on you. I just did not understand why all the concern over a 7 C temperature change.
>
> You have an interesting problem there. It only leaks when cold below freezing. I have no ideas on the cause for that. I agree that if it leaked
> when the valves are shut off, that it is probably a bag leak but I also have never worked on a 4 bag system so I do not understand the plumbing
> involved.
>
> On the soapy water idea, How about using some windshield solvent and soap mixed together? I have never tried that. Maybe that mix will not bubble.
>

My left front tire will hold air all year. Except during the very cold
days of winter. Then it will go flat. Have never found leaks with water
and bubbles.

--
Gary W. Mills
Livonia, MI
. ___________
./_][__][] []| 1974 GMC M/H
.*O-------OO-* Painted Desert


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1974 GMC 260
Tangerine Dream
Livonia Michigan
Re: [GMCnet] Required air pressure for quad bag rear suspension [message #329234 is a reply to message #329230] Sat, 17 February 2018 11:00 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
WE supply on ours and Coop units the DOT fittings that are used on the Big
rigs, so if installed carefully they will hold the air long enough.
You also need to understand that there is no such thing as a Perfict work
on anything.


On Sat, Feb 17, 2018 at 8:38 AM, Gary Mills wrote:

> On 2/17/2018 6:02 AM, Ken Burton wrote:
>
>> OK Gordon. I was not picking on you. I just did not understand why all
>> the concern over a 7 C temperature change.
>>
>> You have an interesting problem there. It only leaks when cold below
>> freezing. I have no ideas on the cause for that. I agree that if it leaked
>> when the valves are shut off, that it is probably a bag leak but I also
>> have never worked on a 4 bag system so I do not understand the plumbing
>> involved.
>>
>> On the soapy water idea, How about using some windshield solvent and soap
>> mixed together? I have never tried that. Maybe that mix will not bubble.
>>
>>
>
> My left front tire will hold air all year. Except during the very cold
> days of winter. Then it will go flat. Have never found leaks with water and
> bubbles.
>
> --
> Gary W. Mills
> Livonia, MI
> . ___________
> ./_][__][] []| 1974 GMC M/H
> .*O-------OO-* Painted Desert
>
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--
Jim Kanomata
Applied/GMC, Newark,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
Re: Required air pressure for quad bag rear suspension [message #329242 is a reply to message #329225] Sat, 17 February 2018 12:51 Go to previous messageGo to next message
NextGenGMC is currently offline  NextGenGMC   United States
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Location: Washington State
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Ken Burton wrote on Sat, 17 February 2018 03:02
OK Gordon. I was not picking on you. I just did not understand why all the concern over a 7 C temperature change.

You have an interesting problem there. It only leaks when cold below freezing. I have no ideas on the cause for that. I agree that if it leaked when the valves are shut off, that it is probably a bag leak but I also have never worked on a 4 bag system so I do not understand the plumbing involved.

On the soapy water idea, How about using some windshield solvent and soap mixed together? I have never tried that. Maybe that mix will not bubble.


What about using RV antifreeze with dish soap mixed into it?


Vadim Jitkov '76 Glenbrook 26' Pullman, WA
Re: [GMCnet] Required air pressure for quad bag rear suspension [message #329245 is a reply to message #329230] Sat, 17 February 2018 14:54 Go to previous messageGo to next message
k2gkk is currently offline  k2gkk   United States
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Registered: November 2009
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Senior Member
Might be a bit of rust or dirt on the rim or even the tire! Low temps cause one or both to shrink a very small bit? Demount tire and hit both the rim and the tire bead with some fine grit sandpaper?


D C "Mac" Macdonald
Amateur Radio K2GKK
Since 30 November '53
USAF and FAA, Retired
Member GMCMI & Classics
Oklahoma City, OK
"The Money Pit"
TZE166V101966
'76 ex-Palm Beach
k2gkk + hotmail dot com



________________________________
From: Gmclist on behalf of Gary Mills
Sent: Saturday, February 17, 2018 10:38
To: gmclist@list.gmcnet.org
Subject: Re: [GMCnet] Required air pressure for quad bag rear suspension

On 2/17/2018 6:02 AM, Ken Burton wrote:
> OK Gordon. I was not picking on you. I just did not understand why all the concern over a 7 C temperature change.
>
> You have an interesting problem there. It only leaks when cold below freezing. I have no ideas on the cause for that. I agree that if it leaked
> when the valves are shut off, that it is probably a bag leak but I also have never worked on a 4 bag system so I do not understand the plumbing
> involved.
>
> On the soapy water idea, How about using some windshield solvent and soap mixed together? I have never tried that. Maybe that mix will not bubble.
>

My left front tire will hold air all year. Except during the very cold
days of winter. Then it will go flat. Have never found leaks with water
and bubbles.

--
Gary W. Mills
Livonia, MI
. ___________
./_][__][] []| 1974 GMC M/H
.*O-------OO-* Painted Desert

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Re: [GMCnet] Required air pressure for quad bag rear suspension [message #329261 is a reply to message #329245] Sun, 18 February 2018 09:35 Go to previous messageGo to next message
Tangerine is currently offline  Tangerine   United States
Messages: 192
Registered: February 2004
Location: Livonia, MI
Karma: 0
Senior Member
On 2/17/2018 3:54 PM, D C _Mac_ Macdonald wrote:
> Might be a bit of rust or dirt on the rim or even the tire! Low temps cause one or both to shrink a very small bit? Demount tire and hit both the rim and the tire bead with some fine grit sandpaper?
>
>
> D C "Mac" Macdonald
> Amateur Radio K2GKK
> Since 30 November '53
> USAF and FAA, Retired
> Member GMCMI & Classics
> Oklahoma City, OK
> "The Money Pit"
> TZE166V101966
> '76 ex-Palm Beach
> k2gkk + hotmail dot com
>
>
>
> ________________________________
> From: Gmclist on behalf of Gary Mills
> Sent: Saturday, February 17, 2018 10:38
> To: gmclist@list.gmcnet.org
> Subject: Re: [GMCnet] Required air pressure for quad bag rear suspension
>
> On 2/17/2018 6:02 AM, Ken Burton wrote:
>> OK Gordon. I was not picking on you. I just did not understand why all the concern over a 7 C temperature change.
>>
>> You have an interesting problem there. It only leaks when cold below freezing. I have no ideas on the cause for that. I agree that if it leaked
>> when the valves are shut off, that it is probably a bag leak but I also have never worked on a 4 bag system so I do not understand the plumbing
>> involved.
>>
>> On the soapy water idea, How about using some windshield solvent and soap mixed together? I have never tried that. Maybe that mix will not bubble.
>>
> My left front tire will hold air all year. Except during the very cold
> days of winter. Then it will go flat. Have never found leaks with water
> and bubbles.
>
THX Mac  The last time I put a new tire on that rim.  I wire wheeled and
painted the rim. Next time I will replace the valve stem. Should work
unless there is a hair line crack in the rim somewhere.

--
Gary W. Mills
Livonia, MI
. ___________
./_][__][] []| 1974 GMC M/H
.*O-------OO-* Painted Desert


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1974 GMC 260
Tangerine Dream
Livonia Michigan
Re: [GMCnet] Required air pressure for quad bag rear suspension [message #329264 is a reply to message #329261] Sun, 18 February 2018 12:42 Go to previous messageGo to next message
jimk is currently offline  jimk   United States
Messages: 6734
Registered: July 2006
Location: Belmont, CA
Karma: 9
Senior Member
Make sure the rim has a R stamped on it as the old rims were not rated for
Radial tire , also the 5year rule. Sounds redicules, but based on our
customers and my experiance, it is vey valid.

On Sun, Feb 18, 2018 at 7:35 AM, Gary Mills wrote:

> On 2/17/2018 3:54 PM, D C _Mac_ Macdonald wrote:
>
>> Might be a bit of rust or dirt on the rim or even the tire! Low temps
>> cause one or both to shrink a very small bit? Demount tire and hit both
>> the rim and the tire bead with some fine grit sandpaper?
>>
>>
>> D C "Mac" Macdonald
>> Amateur Radio K2GKK
>> Since 30 November '53
>> USAF and FAA, Retired
>> Member GMCMI & Classics
>> Oklahoma City, OK
>> "The Money Pit"
>> TZE166V101966
>> '76 ex-Palm Beach
>> k2gkk + hotmail dot com
>>
>>
>>
>> ________________________________
>> From: Gmclist on behalf of Gary Mills > daveel@ix.netcom.com>
>> Sent: Saturday, February 17, 2018 10:38
>> To: gmclist@list.gmcnet.org
>> Subject: Re: [GMCnet] Required air pressure for quad bag rear suspension
>>
>> On 2/17/2018 6:02 AM, Ken Burton wrote:
>>
>>> OK Gordon. I was not picking on you. I just did not understand why all
>>> the concern over a 7 C temperature change.
>>>
>>> You have an interesting problem there. It only leaks when cold below
>>> freezing. I have no ideas on the cause for that. I agree that if it leaked
>>> when the valves are shut off, that it is probably a bag leak but I also
>>> have never worked on a 4 bag system so I do not understand the plumbing
>>> involved.
>>>
>>> On the soapy water idea, How about using some windshield solvent and
>>> soap mixed together? I have never tried that. Maybe that mix will not
>>> bubble.
>>>
>>> My left front tire will hold air all year. Except during the very cold
>> days of winter. Then it will go flat. Have never found leaks with water
>> and bubbles.
>>
>> THX Mac The last time I put a new tire on that rim. I wire wheeled and
> painted the rim. Next time I will replace the valve stem. Should work
> unless there is a hair line crack in the rim somewhere.
>
>
> --
> Gary W. Mills
> Livonia, MI
> . ___________
> ./_][__][] []| 1974 GMC M/H
> .*O-------OO-* Painted Desert
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>



--
Jim Kanomata
Applied/GMC, Newark,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
Re: [GMCnet] Required air pressure for quad bag rear suspension [message #329265 is a reply to message #329264] Sun, 18 February 2018 12:56 Go to previous messageGo to next message
James Hupy is currently offline  James Hupy   United States
Messages: 6806
Registered: May 2010
Karma: -62
Senior Member
If you are still running 16.5" steel rims, you more than likely have a
welded spot seeping air. CURE? find the leak and grind it and weld it, or,
replace the wheel, or replace all 7 wheels with eagle or Alcoa hub centered
alloy wheels.
Jim Hupy
Salem, Or
78 GMC ROYALE 403

On Feb 18, 2018 10:43 AM, "Jim Kanomata" wrote:

> Make sure the rim has a R stamped on it as the old rims were not rated for
> Radial tire , also the 5year rule. Sounds redicules, but based on our
> customers and my experiance, it is vey valid.
>
> On Sun, Feb 18, 2018 at 7:35 AM, Gary Mills wrote:
>
>> On 2/17/2018 3:54 PM, D C _Mac_ Macdonald wrote:
>>
>>> Might be a bit of rust or dirt on the rim or even the tire! Low temps
>>> cause one or both to shrink a very small bit? Demount tire and hit both
>>> the rim and the tire bead with some fine grit sandpaper?
>>>
>>>
>>> D C "Mac" Macdonald
>>> Amateur Radio K2GKK
>>> Since 30 November '53
>>> USAF and FAA, Retired
>>> Member GMCMI & Classics
>>> Oklahoma City, OK
>>> "The Money Pit"
>>> TZE166V101966
>>> '76 ex-Palm Beach
>>> k2gkk + hotmail dot com
>>>
>>>
>>>
>>> ________________________________
>>> From: Gmclist on behalf of Gary
> Mills >> daveel@ix.netcom.com>
>>> Sent: Saturday, February 17, 2018 10:38
>>> To: gmclist@list.gmcnet.org
>>> Subject: Re: [GMCnet] Required air pressure for quad bag rear suspension
>>>
>>> On 2/17/2018 6:02 AM, Ken Burton wrote:
>>>
>>>> OK Gordon. I was not picking on you. I just did not understand why
> all
>>>> the concern over a 7 C temperature change.
>>>>
>>>> You have an interesting problem there. It only leaks when cold below
>>>> freezing. I have no ideas on the cause for that. I agree that if it
> leaked
>>>> when the valves are shut off, that it is probably a bag leak but I also
>>>> have never worked on a 4 bag system so I do not understand the plumbing
>>>> involved.
>>>>
>>>> On the soapy water idea, How about using some windshield solvent and
>>>> soap mixed together? I have never tried that. Maybe that mix will not
>>>> bubble.
>>>>
>>>> My left front tire will hold air all year. Except during the very cold
>>> days of winter. Then it will go flat. Have never found leaks with water
>>> and bubbles.
>>>
>>> THX Mac The last time I put a new tire on that rim. I wire wheeled and
>> painted the rim. Next time I will replace the valve stem. Should work
>> unless there is a hair line crack in the rim somewhere.
>>
>>
>> --
>> Gary W. Mills
>> Livonia, MI
>> . ___________
>> ./_][__][] []| 1974 GMC M/H
>> .*O-------OO-* Painted Desert
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>
>
>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk@appliedairfilters.com
> http://www.appliedgmc.com
> 1-800-752-7502
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Re: [GMCnet] Required air pressure for quad bag rear suspension [message #329276 is a reply to message #329265] Mon, 19 February 2018 05:37 Go to previous messageGo to next message
Tangerine is currently offline  Tangerine   United States
Messages: 192
Registered: February 2004
Location: Livonia, MI
Karma: 0
Senior Member
THX  Jim Hupy
I would like to get all 7 wheels replaced with eagle hub centered alloy
wheels.  I am waiting for Jim K to have the Hot Shot wheel design
reproduced.

On 2/18/2018 1:56 PM, James Hupy wrote:
> If you are still running 16.5" steel rims, you more than likely have a
> welded spot seeping air. CURE? find the leak and grind it and weld it, or,
> replace the wheel, or replace all 7 wheels with eagle or Alcoa hub centered
> alloy wheels.
> Jim Hupy
> Salem, Or
> 78 GMC ROYALE 403
>
> On Feb 18, 2018 10:43 AM, "Jim Kanomata" wrote:
>
>
> My left front tire will hold air all year. Except during the very cold
> days of winter. Then it will go flat. Have never found leaks with water
> and bubbles.
>
> THX Mac The last time I put a new tire on that rim. I wire wheeled and
> painted the rim. Next time I will replace the valve stem. Should work
> unless there is a hair line crack in the rim somewhere.
>
>
> --
> Gary W. Mills
> Livonia, MI
> . ___________
> ./_][__][] []| 1974 GMC M/H
> .*O-------OO-* Painted Desert

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1974 GMC 260
Tangerine Dream
Livonia Michigan
Re: [GMCnet] Required air pressure for quad bag rear suspension [message #329344 is a reply to message #329276] Tue, 20 February 2018 19:31 Go to previous messageGo to next message
Bullitthead is currently offline  Bullitthead   United States
Messages: 1411
Registered: November 2013
Karma: 5
Senior Member
The GMC right side used to fall down at 15 degrees F. This was when I winterized it and allowed it to get cold inside as well. It was 23 degrees inside when it was 15 outside. Before I put a block under the right rear, I learned valuable lesson about door not opening enough for me to get in and correct the situation Laughing Could not find leak after pumping system back up while running engine and compressor. Surmised it was the supply line to the right bag, and the control valve also leaking system air to the bag when there was enough pressure differential. Bags and system held up all the rest of the year. Found problems next temp drop(using leak check that doesn't freeze)...PLASTICS...did not warm up engine or interior, used external compressor for air in system. In addition to the internal valve leak, the plastic hose compression type connection for the right bag leaked when it got that cold. Fixed the hose with warmth followed with a little bit of disassembly and rework. Still haven't found the rebuild kit for the valves, but was informed of JR's replacements. I'm too cheap right now for new valves, and have further system mods being added on which may get incorporated into that system. There are some compression unions under the coach that didn't leak back then, but after they got blasted with exhaust leakage last summer (muffler explosion) they leaked to the point that the system only stayed up for about 15 minutes. Was able to stop leakage by tightening, but reworked 2 of the connections to be sure. Those connections are not supposed to be there, I can tell by the way the hoses ended up being routed. Muff explosion due to ignition cutoff from electrical spike must have happened to the P.O. also Confused The temperature changes really affect the plastics...all of them...



Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
Re: [GMCnet] Required air pressure for quad bag rear suspension [message #329345 is a reply to message #329344] Tue, 20 February 2018 19:36 Go to previous messageGo to previous message
Bullitthead is currently offline  Bullitthead   United States
Messages: 1411
Registered: November 2013
Karma: 5
Senior Member
"I am waiting for Jim K to have the Hot Shot wheel design reproduced."

Is this a rumor or a possibility? I really like that wheel design from Alcoa and admire Eric Tanner's set on his. I would be a customer for those Cool


Terry Kelpien ASE Master Technician 73 Glacier 260 Smithfield, Va.
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