viair

Larry,
I ran the stock Dana on my '73 for years, including after I installed one of JimK's quadrabag systems. I ran it with the pressure switch set to
90--120psi and never had any problems with it. I have since switched to a Vair because I think it's a little more robust, but the whole thing has been
trouble free. I'm unclear on your suggestion of more psi.
--
Douglas & Virginia Smith
dsmithy18 at gmail
Lincoln Nebraska
’73 “Canyonlands” since ‘95: "Wanabizo";
Quadrabag/6 wheel disks/3:70 final/Paterson QuadraJet/Thorley’s/Alloy wheels(finally!)/Sundry other
 
> Larry,
> I ran the stock Dana on my '73 for years, including after I installed one of JimK's quadrabag systems. I ran it with the pressure switch set to
> 90--120psi and never had any problems with it. I have since switched to a Vair because I think it's a little more robust, but the whole thing has
> been trouble free. I'm unclear on your suggestion of more psi.

My system was set at 90-120lbs when I put the 4bag on. The 4bag runs down the road at normal height at 110lbs. So when I get to a camp site, and go to
raise for leveling, since the 110lbs in the bag is so close to what is waiting in the reservoir, the compressor won't come on unless I let some air
out of the system to 90lbs That then allows me to run it up to 120lbs. But then 120 is not enough for full extension. So, I set the off at 150 and
found that at times I still had times when the bags pressure of 115 was at the reservoir pressure of 115, and would still not come on. For now, I am
just letting some air out of the reservoir so I can go to 150. Hoping at sometime in the future to go with a 2 gallon reservoir and maybe up to 175.
JWID
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Different Larry, but I just replaced my very tired compressor with a new Viair 450c and was stunned by how quickly it came up to pressure. Now I have
to put on my pith helmet and go on safari hunting for the elusive air leaks.
I mean WOW!
I should have done this long ago.
--
Larry Davick
A Mystery Machine
1976(ish) Palm Beach
Fremont, Ca
Howell EFI + EBL + Electronic Dizzy
 
> Different Larry, but I just replaced my very tired compressor with a new Viair 450c and was stunned by how quickly it came up to pressure. Now I
> have to put on my pith helmet and go on safari hunting for the elusive air leaks.
> I mean WOW!
> I should have done this long ago.

Ya, I have an older Viair that I put in back in 2004. Don't know what model it is, but was a little quicker in raising pressure than the old stock
system. I can see a 450 in my future. Can't right now. Just had a root canal. Holly cow did that put a drain on the budget! Deep thoughts when your
mouth has a bigger effect on living than your GMC. :roll:
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
> > Larry,
> > I ran the stock Dana on my '73 for years, including after I installed one of JimK's quadrabag systems. I ran it with the pressure switch set
> > to 90--120psi and never had any problems with it. I have since switched to a Vair because I think it's a little more robust, but the whole thing
> > has been trouble free. I'm unclear on your suggestion of more psi.
>
> My system was set at 90-120lbs when I put the 4bag on. The 4bag runs down the road at normal height at 110lbs. So when I get to a camp site, and
> go to raise for leveling, since the 110lbs in the bag is so close to what is waiting in the reservoir, the compressor won't come on unless I let
> some air out of the system to 90lbs That then allows me to run it up to 120lbs. But then 120 is not enough for full extension. So, I set the off at
> 150 and found that at times I still had times when the bags pressure of 115 was at the reservoir pressure of 115, and would still not come on. For
> now, I am just letting some air out of the reservoir so I can go to 150. Hoping at sometime in the future to go with a 2 gallon reservoir and maybe
> up to 175. JWID

What you describe was also an annoying problem for me. I also have a quadrabag system. To solve it, I installed a pressure regulator and set it to
125 and the reservoir pressure to 150. That seems to have solved the problem for me. However, it seems with quadrabag I can't raise the coach as
much as I used to with the OEM system. Maybe that is my imagination. Maybe I should up the regulator pressure, but I am concerned about over
pressurizing the bags. Maybe that is unfounded.

--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com


Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Lenzi stuff, Manny Tranny etc.
 
> > > Larry,
> > > I ran the stock Dana on my '73 for years, including after I installed one of JimK's quadrabag systems. I ran it with the pressure switch
> > > set to 90--120psi and never had any problems with it. I have since switched to a Vair because I think it's a little more robust, but the whole
> > > thing has been trouble free. I'm unclear on your suggestion of more psi.
> >
> > My system was set at 90-120lbs when I put the 4bag on. The 4bag runs down the road at normal height at 110lbs. So when I get to a camp site,
> > and go to raise for leveling, since the 110lbs in the bag is so close to what is waiting in the reservoir, the compressor won't come on unless I
> > let some air out of the system to 90lbs That then allows me to run it up to 120lbs. But then 120 is not enough for full extension. So, I set the
> > off at 150 and found that at times I still had times when the bags pressure of 115 was at the reservoir pressure of 115, and would still not come
> > on. For now, I am just letting some air out of the reservoir so I can go to 150. Hoping at sometime in the future to go with a 2 gallon reservoir
> > and maybe up to 175. JWID
>
> What you describe was also an annoying problem for me. I also have a quadrabag system. To solve it, I installed a pressure regulator and set it
> to 125 and the reservoir pressure to 150. That seems to have solved the problem for me. However, it seems with quadrabag I can't raise the coach
> as much as I used to with the OEM system. Maybe that is my imagination. Maybe I should up the regulator pressure, but I am concerned about over
> pressurizing the bags. Maybe that is unfounded.

Find out what the "Burst" pressure on the bags is. That, I would think, should give you an idea what your max pressure could be. JWIT
--
Larry
78 Royale w/500 Caddy
Menomonie, WI.
 
Sounds to me like a parking problem. Maybe you need to find a Walmart lot
that is more level than the ones you are using. (Grin) You can accomplish
the same thing by lowering the other side. Just a suggestion. On the quad
bag systems that I have worked on, they seem to not raise as high as a
stock system by about 3/4". But, the shocks limit the height. If you reach
the end of their travel you are done.
Jim Hupy
Salem, Oregon

On Sun, Oct 18, 2020, 1:05 PM Larry via Gmclist
wrote:

> > > > Larry,
> > > > I ran the stock Dana on my '73 for years, including after I
> installed one of JimK's quadrabag systems. I ran it with the pressure switch
> > > > set to 90--120psi and never had any problems with it. I have since
> switched to a Vair because I think it's a little more robust, but the whole
> > > > thing has been trouble free. I'm unclear on your suggestion of more
> psi.
> > >
> > > My system was set at 90-120lbs when I put the 4bag on. The 4bag runs
> down the road at normal height at 110lbs. So when I get to a camp site,
> > > and go to raise for leveling, since the 110lbs in the bag is so close
> to what is waiting in the reservoir, the compressor won't come on unless I
> > > let some air out of the system to 90lbs That then allows me to run it
> up to 120lbs. But then 120 is not enough for full extension. So, I set the
> > > off at 150 and found that at times I still had times when the bags
> pressure of 115 was at the reservoir pressure of 115, and would still not
> come
> > > on. For now, I am just letting some air out of the reservoir so I can
> go to 150. Hoping at sometime in the future to go with a 2 gallon reservoir
> > > and maybe up to 175. JWID
> >
> > What you describe was also an annoying problem for me. I also have a
> quadrabag system. To solve it, I installed a pressure regulator and set it
> > to 125 and the reservoir pressure to 150. That seems to have solved the
> problem for me. However, it seems with quadrabag I can't raise the coach
> > as much as I used to with the OEM system. Maybe that is my
> imagination. Maybe I should up the regulator pressure, but I am concerned
> about over
> > pressurizing the bags. Maybe that is unfounded.
>
> Find out what the "Burst" pressure on the bags is. That, I would think,
> should give you an idea what your max pressure could be. JWIT
> --
> Larry
> 78 Royale w/500 Caddy
> Menomonie, WI.
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
 
Looking up the specifications on the air springs will make for an interesting read.

I’m looking at a number of data sheets right now on “common” convoluted air springs.

I’m not seeing more than 100 PSI recommended.

https://www.mrostop.com/media/uploads/firestone_pdfs/W01-358-6947.pdf https://www.mrostop.com/media/uploads/firestone_pdfs/W01-358-6947.pdf

This covers the air spring (Firestones term) that I’m using on my coach (Ferrara Bags).

No, I won’t make the comment I wanted to — but, Air Springs Matter.

Dolph

DE AD0LF

Wheeling, West Virginia

1977 26’ ex-PalmBeach
Howell EFI & EBL, Reaction Arms, Manny Transmission

“The Aluminum and Fiberglass Mistress”

|[ ]~~~[][ ][] \
"--OO--[]---O-"

>

>>>> Larry,
>>>> I ran the stock Dana on my '73 for years, including after I installed one of JimK's quadrabag systems. I ran it with the pressure switch
>>>> set to 90--120psi and never had any problems with it. I have since switched to a Vair because I think it's a little more robust, but the whole
>>>> thing has been trouble free. I'm unclear on your suggestion of more psi.
>>>
>>> My system was set at 90-120lbs when I put the 4bag on. The 4bag runs down the road at normal height at 110lbs. So when I get to a camp site,
>>> and go to raise for leveling, since the 110lbs in the bag is so close to what is waiting in the reservoir, the compressor won't come on unless I
>>> let some air out of the system to 90lbs That then allows me to run it up to 120lbs. But then 120 is not enough for full extension. So, I set the
>>> off at 150 and found that at times I still had times when the bags pressure of 115 was at the reservoir pressure of 115, and would still not come
>>> on. For now, I am just letting some air out of the reservoir so I can go to 150. Hoping at sometime in the future to go with a 2 gallon reservoir
>>> and maybe up to 175. JWID
>>
>> What you describe was also an annoying problem for me. I also have a quadrabag system. To solve it, I installed a pressure regulator and set it
>> to 125 and the reservoir pressure to 150. That seems to have solved the problem for me. However, it seems with quadrabag I can't raise the coach
>> as much as I used to with the OEM system. Maybe that is my imagination. Maybe I should up the regulator pressure, but I am concerned about over
>> pressurizing the bags. Maybe that is unfounded.
>
> Find out what the "Burst" pressure on the bags is. That, I would think, should give you an idea what your max pressure could be. JWIT
> --
> Larry
> 78 Royale w/500 Caddy
> Menomonie, WI.
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
> Sounds to me like a parking problem. Maybe you need to find a Walmart lot
> that is more level than the ones you are using. (Grin) You can accomplish
> the same thing by lowering the other side. Just a suggestion. On the quad
> bag systems that I have worked on, they seem to not raise as high as a
> stock system by about 3/4". But, the shocks limit the height. If you reach
> the end of their travel you are done.
> Jim Hupy
> Salem, Oregon

I pretty much have learned how to park in unlevel sites. It is not as much a problem as it used to be. If I do have a severe unlevel site, I get out
the jack hooks and bottle jacks, or the leveling blocks I carry. I can get it level most places. I did try higher pressure but was concerned about
breaking something.
--
Richard
76 Palm Beach
SE Michigan
www.PalmBeachGMC.com


Coop Roller Cam 455, Howell TBI + EBL, 3.42 FD, Quadra Bag, Macerator, Lenzi stuff, Manny Tranny etc.
 
Larry,
I actually do exactly as you do with driving/leveling. I just assumed that bleeding air to start the compressor was normal operation. Sigh.
--
Douglas & Virginia Smith
dsmithy18 at gmail
Lincoln Nebraska
’73 “Canyonlands” since ‘95: "Wanabizo";
Quadrabag/6 wheel disks/3:70 final/Paterson QuadraJet/Thorley’s/Alloy wheels(finally!)/Sundry other
 
Dolph,

Page 14 in the link you sent goes into load and pressure suggestions. Looks
like 100psi for two ply bags and 175 for four ply.

Sully
Bellevue wa

On Sun, Oct 18, 2020 at 2:17 PM Dolph Santorine via Gmclist <

> Looking up the specifications on the air springs will make for an
> interesting read.
>
> I’m looking at a number of data sheets right now on “common” convoluted
> air springs.
>
> I’m not seeing more than 100 PSI recommended.
>
> https://www.mrostop.com/media/uploads/firestone_pdfs/W01-358-6947.pdf <
> https://www.mrostop.com/media/uploads/firestone_pdfs/W01-358-6947.pdf>
>
> This covers the air spring (Firestones term) that I’m using on my coach
> (Ferrara Bags).
>
> No, I won’t make the comment I wanted to — but, Air Springs Matter.
>
>
> Dolph
>
> DE AD0LF
>
> Wheeling, West Virginia
>
> 1977 26’ ex-PalmBeach
> Howell EFI & EBL, Reaction Arms, Manny Transmission
>
> “The Aluminum and Fiberglass Mistress”
>
> |[ ]~~~[][ ][] \
> "--OO--[]---O-"
>
> > On Oct 18, 2020, at 4:04 PM, Larry via Gmclist

> >

> >>>> Larry,
> >>>> I ran the stock Dana on my '73 for years, including after I installed
> one of JimK's quadrabag systems. I ran it with the pressure switch
> >>>> set to 90--120psi and never had any problems with it. I have since
> switched to a Vair because I think it's a little more robust, but the whole
> >>>> thing has been trouble free. I'm unclear on your suggestion of more
> psi.
> >>>
> >>> My system was set at 90-120lbs when I put the 4bag on. The 4bag runs
> down the road at normal height at 110lbs. So when I get to a camp site,
> >>> and go to raise for leveling, since the 110lbs in the bag is so close
> to what is waiting in the reservoir, the compressor won't come on unless I
> >>> let some air out of the system to 90lbs That then allows me to run it
> up to 120lbs. But then 120 is not enough for full extension. So, I set the
> >>> off at 150 and found that at times I still had times when the bags
> pressure of 115 was at the reservoir pressure of 115, and would still not
> come
> >>> on. For now, I am just letting some air out of the reservoir so I can
> go to 150. Hoping at sometime in the future to go with a 2 gallon reservoir
> >>> and maybe up to 175. JWID
> >>
> >> What you describe was also an annoying problem for me. I also have a
> quadrabag system. To solve it, I installed a pressure regulator and set it
> >> to 125 and the reservoir pressure to 150. That seems to have solved
> the problem for me. However, it seems with quadrabag I can't raise the
> coach
> >> as much as I used to with the OEM system. Maybe that is my
> imagination. Maybe I should up the regulator pressure, but I am concerned
> about over
> >> pressurizing the bags. Maybe that is unfounded.
> >
> > Find out what the "Burst" pressure on the bags is. That, I would think,
> should give you an idea what your max pressure could be. JWIT
> > --
> > Larry
> > 78 Royale w/500 Caddy
> > Menomonie, WI.
> >
> > _______________________________________________
> > 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
>
 
I solved the problem of being stuck between the desired pressure and the kick on pressure by adding a manually switched pump. It gives me a back up if
one fails, and when the auto pump is content where it is and I am not - I just hit the manual one. Plus in the years where I have had a slow (day or
two) leak, it gives me two to pump everything up from zero. I put the manual one on the house battery side, and left the auto pump on the switched
ignition side like OEM.

--
1975 Glenbrook, 1978 Royale rear bath
Raleigh, NC
 
Tilerpep,
Good idea. That is exactly what I'll do, with the insertion of a 150psi limit switch.
I'm afraid that when I flip on the manual switch, in the busyness of parking/leveling/plugging in/pouring an adult beverage, I might forget it on so
the Vair soldiers on forever.
--
Douglas & Virginia Smith
dsmithy18 at gmail
Lincoln Nebraska
’73 “Canyonlands” since ‘95: "Wanabizo";
Quadrabag/6 wheel disks/3:70 final/Paterson QuadraJet/Thorley’s/Alloy wheels(finally!)/Sundry other
 
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