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I Need Advice about Air Bag System Leaks [message #159724] Thu, 09 February 2012 12:48 Go to next message
bess is currently offline  bess   United States
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Can Someone Please give me some Advice on what to do Next. Keep in Mind that I am too Old and Not Mechanically Inclined to Fix Anything Myself. The Motorhome is Leaking Air. I have taken it to 2 Different Places trying to find the Leaks. Both Places said the Air Bags are Not Leaking. One place told me there was a Very Small Leak in a Plastic Washer close to the Air Bag that didn't amount to much which is on the Drivers side - the Other Place worked on it for a number of hours and said there were 5 Leaks alone on the Drivers Side in the Fittings that they fixed but there was still another leak somewhere because in a 24 hour Period - it was going down 1/2". After they fixed the leaks they found - it does ride higher and I believe drives a little better than it did. On the way home, I left the switch on Auto instead of Hold and the compressor came on several times in 12 miles. I have had it home 10 days now - had the Switch on Hold - and still the back end is sinking. The Drivers Side has dropped down 2 1/2" from the measurement I took after the compressor had the air bags full 10 days ago - the Passenger Side is down 5 1/2". The last place that fixerd it said it would be quite expensive to take the whole system out and replace it. I have already spent over $400 chasing Air Leaks. Does Anyone have Any Ideas what I should try next or should I just leave it alone? I want to take a trip in a month or so and am trying to get the problems fixed in advance.

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: I Need Advice about Air Bag System Leaks [message #159726 is a reply to message #159724] Thu, 09 February 2012 12:54 Go to previous messageGo to next message
Bob de Kruyff   United States
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Location: Chandler, AZ
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bess wrote on Thu, 09 February 2012 11:48

Can Someone Please give me some Advice on what to do Next. Keep in Mind that I am too Old and Not Mechanically Inclined to Fix Anything Myself. The Motorhome is Leaking Air. I have taken it to 2 Different Places trying to find the Leaks. Both Places said the Air Bags are Not Leaking. One place told me there was a Very Small Leak in a Plastic Washer close to the Air Bag that didn't amount to much which is on the Drivers side - the Other Place worked on it for a number of hours and said there were 5 Leaks alone on the Drivers Side in the Fittings that they fixed but there was still another leak somewhere because in a 24 hour Period - it was going down 1/2". After they fixed the leaks they found - it does ride higher and I believe drives a little better than it did. On the way home, I left the switch on Auto instead of Hold and the compressor came on several times in 12 miles. I have had it home 10 days now - had the Switch on Hold - and still the back end is sinking. The Drivers Side has dropped down 2 1/2" from the measurement I took after the compressor had the air bags full 10 days ago - the Passenger Side is down 5 1/2". The last place that fixerd it said it would be quite expensive to take the whole system out and replace it. I have already spent over $400 chasing Air Leaks. Does Anyone have Any Ideas what I should try next or should I just leave it alone? I want to take a trip in a month or so and am trying to get the problems fixed in advance.


Bess-there may be a GMC'r close by that can help, but frankly, I think you can get by with that amount of leakage depending how you use your coach. If it sags only 1/2" in 24 hours, you should be able to use it with no problems and the compressor can handle that. If the coach is parked without using it, it won't hurt it to just let it go down in the rear.


Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: I Need Advice about Air Bag System Leaks [message #159728 is a reply to message #159726] Thu, 09 February 2012 13:05 Go to previous messageGo to next message
bess is currently offline  bess   United States
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Thanks Bob, I really didn't know if I should get something done before I try to go somewhere or not. The longest trip I have been on before I got it "fixed" was under 150 miles and the rear sank when parked on that one too and I was only parked 3 days.

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: I Need Advice about Air Bag System Leaks [message #159729 is a reply to message #159728] Thu, 09 February 2012 13:12 Go to previous messageGo to next message
Bob de Kruyff   United States
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Some others may disagree with me, but you could easily just start it once a day for a few minutes to bring it back up. There are other solutions such as shut off valves but you will need someone to help with the install even though they are an inexpensive work-around.

Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: I Need Advice about Air Bag System Leaks [message #159732 is a reply to message #159729] Thu, 09 February 2012 14:12 Go to previous messageGo to next message
tphipps is currently offline  tphipps   United States
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Bess, It would help if we knew what air system was installed in the coach. Since it sounds like you have one compressor (that you can hear)(up front in the engine compartment, mounted to the driver's side of the radiator), I would assume that you have the original power level system. A major leak point are the old control valves. If you have the power level valves located right near your driver side right knee (in lower dash), you can remove the four screws that hold it in place (carefully, because the plastic is brittle and old) pull it out just a little (so that you can see the back), start the engine, run the air system and when the air tank is full, and the compressor cuts off, spray the backside of the valve body (where the air lines come in) with some soapy water and look for bubbles. You may have to turn the knobs to the travel position for air to move into the valve body. If it bubbles, you know where to apply your repair efforts.
If everything is working fine, you can drive with the air compressor cycling on and off. It may be a minor annoyance, but will not cause any damage.
Tom Phipps, MS II


2012 Phoenix Cruiser model 2552 KA4CSG
Re: [GMCnet] I Need Advice about Air Bag System Leaks [message #159744 is a reply to message #159724] Thu, 09 February 2012 15:40 Go to previous messageGo to next message
USAussie is currently offline  USAussie   United States
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Bes,

If you want to have it repaired by someone that KNOWS what they're doing contact Tom Hampton. I realize that his shop is 460 miles
from Elvaston but you've already spent over $400 chasing the leaks without fixing the problem money spent to get your GMC over to
his shop would be money well spent as he WILL fix it! Be advised, however, that Tom works by appointment only and it may take awhile
to get into his shop.

Here's the contact details:

Tom & Nina Hampton
Grandview Motorhomes
13880 West Weaver Road
Marysville, Ohio 43040
Tel: (937) 644-4238
Email: grandviewh@peoplepc.com

I have Cc'd Tom on this email to give him a heads up that you might be contacting him.

Regards,
Rob M.


-----Original Message-----
From: Bes Brenenstall

Can Someone Please give me some Advice on what to do Next. Keep in Mind that I am too Old and Not Mechanically Inclined to Fix
Anything Myself. The Motorhome is Leaking Air. I have taken it to 2 Different Places trying to find the Leaks. Both Places said
the Air Bags are Not Leaking. One place told me there was a Very Small Leak in a Plastic Washer close to the Air Bag that didn't
amount to much which is on the Drivers side - the Other Place worked on it for a number of hours and said there were 5 Leaks alone
on the Drivers Side in the Fittings that they fixed but there was still another leak somewhere because in a 24 hour Period - it was
going down 1/2". After they fixed the leaks they found - it does ride higher and I believe drives a little better than it did. On
the way home, I left the switch on Auto instead of Hold and the compressor came on several times in 12 miles. I have had it home
10 days now - had the Switch on Hold - and still the back end is sinking. Th
e Drivers Side has dropped down 2 1/2" from the measurement I took after the compressor had the air bags full 10 days ago - the
Passenger Side is down 5 1/2". The last place that fixerd it said it would be quite expensive to take the whole system out and
replace it. I have already spent over $400 chasing Air Leaks. Does Anyone have Any Ideas what I should try next or should I just
leave it alone? I want to take a trip in a month or so and am trying to get the problems fixed in advance.
--
Bess Brenenstall

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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: I Need Advice about Air Bag System Leaks [message #159750 is a reply to message #159732] Thu, 09 February 2012 16:02 Go to previous messageGo to next message
bess is currently offline  bess   United States
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Hi Tom, What ever was Original to the Birchaven Air System is still on the Motorhome. The Compressor is under the Refrigerator and near the Back of the Motorhome but you can hear it when it comes on. It is a little louder now then before I had it worked on. I started Her up this afternoon to get it back to level and the Compressor ran around 15 minutes to get it aired back up. Yes it has the Original Leveling System too and it is right where you said on the dash near the Knee. I will ask the Guy who worked on it if he checked the valves on the leveling system. When I took it to him - the Passenger Side would level just fine, but the Drivers Side would go down but not back up. He said that this worked just fine now, but I havn't tried it. As long as it won't ruin the compressor when it runs so much - I will leave well enough alone for now. Thanks for Your Help

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: I Need Advice about Air Bag System Leaks [message #159754 is a reply to message #159750] Thu, 09 February 2012 16:15 Go to previous messageGo to next message
sgltrac is currently offline  sgltrac   United States
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Bess, if you get a small handful of blocking to put under the bogie brackets when you park and have leveled out could help a bit. This way once you get to your destination and level the coach with the air system you can shore it up under the bogies and let the system bleed off while you are camped, who cares? When you go to leave turn the system on and the compressor will not need to work nearly as hard to fill back up if the bags are not completely void of air with the coach weight sitting on them. Just don't forget its there and start to drive away Smile
This should get you by until you happen across another GMCer Wink


Sully 77 Royale basket case. Future motorhome land speed record holder(bucket list) Seattle, Wa.
Re: [GMCnet] I Need Advice about Air Bag System Leaks [message #159755 is a reply to message #159744] Thu, 09 February 2012 16:23 Go to previous messageGo to next message
bess is currently offline  bess   United States
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Thanks for the Information Rob. I wrote his name and number down, so maybe in the Spring I can finally get it fixed.

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: I Need Advice about Air Bag System Leaks [message #159759 is a reply to message #159754] Thu, 09 February 2012 16:36 Go to previous messageGo to next message
bess is currently offline  bess   United States
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Thanks for the advice sgltrac, I will definitely do that so it won't be that hard on the compressor. Another Wonderful Black List Member had told me quite awhile ago about blocking the Bogies when I put her away for the Winter to take the Pressure off of the Air Bags so I already have the 4x4s to put under her. What he Didn't realize (because I thought it was "normal") was that there wasn't any pressure on the airbags because the system was leaking air. The Guy I Bought her from told me that when it is parked - it is normal for the back end to go down so I didn't question it.

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: I Need Advice about Air Bag System Leaks [message #159760 is a reply to message #159754] Thu, 09 February 2012 16:37 Go to previous messageGo to next message
chasingsummer is currently offline  chasingsummer   United States
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when mine is parked at the house, i put a block under each bogie (i guess is what it is called) and let air out til coach rest on blocks, other wise my system would leak down close to what yours did. do u have the air cut off valves at the bags?
until air system makes it to the top of my to do list i use them when parked for any lenght of time. . raise or lower to proper height then turn valve at bags off and place knob inside coach to hold.
when i start coach i turn on valve at bags and turn knob to travel. then i spend a minute or 3 doing a walk around. double check air pressure in tires, double check gen cover and propane tank cover are closed. antenna down, etc etc. within this walk around coach is ready to ride.
is anyone on black list close to u? that is where you will find ost of your help with such issues. i have found them eagar to help, as well as more experienced with our coach than anyone else.


brian asheboro, nc 75 eleganza, 74 build 119k miles and counting, DOG HOUSE
Re: I Need Advice about Air Bag System Leaks [message #159764 is a reply to message #159760] Thu, 09 February 2012 16:56 Go to previous messageGo to next message
bess is currently offline  bess   United States
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Brian, I am going down right now and put the blocks under the bogies. I should have kept on doing that so she doesn't get so low. I really thought this last time she would be fixed so she wouldn't sag any more. No, I don't have the shut off valves at the Bags. As far as I know, everything on the airbag system is just as it was when it was made.

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: I Need Advice about Air Bag System Leaks [message #159766 is a reply to message #159764] Thu, 09 February 2012 17:13 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
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Bess, what part of Illinois are you in? What large town are you close to? I am 40 miles west of Cairo in Mo. and will help you if within driving range for a day. The dang air systems can be tricky and I doubt a non GMC shop can fix this for you. They shoot a little soap on the connections and if no bubbles assume no leak. That can be false. Also, how can they be sure it is not a bag unless you have shut offs on them? I would start with shut offs on the bags, air them up, and see if they leak.
You have gotten great advice from my friends here on the net. Thanks for coming here for help. We need all of the owners we can get to come here. You may be able to help me with something one of these times.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: I Need Advice about Air Bag System Leaks [message #159780 is a reply to message #159766] Thu, 09 February 2012 18:08 Go to previous messageGo to next message
bess is currently offline  bess   United States
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Hi Dan, I am straight North of You near Keokuk Ia which is in the Southernmost Point of Iowa. I am just across the river in Illinois about 8 miles. I am Glad to know where you are. . . on the Trip I plan to take, I will be coming down your way and it's good to know there is someone on the first leg of my trip. I plan to spend the first night in Sikeston, Mo. - So if you get a call for help from this Old Couple !!! you will remember me, but hopefully everything is going to go Smoothly. I don't really know how both Shops could tell there wern't any leaks in the air bags - but both said there wasn't. I know in the Spring when it is warmer, it is on my list of things to get Fixed.

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: I Need Advice about Air Bag System Leaks [message #159781 is a reply to message #159780] Thu, 09 February 2012 18:14 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
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Oh good Bess. Call me and give me some advance warning so I can run over and see you. If the leak is still causing you problems we can take a look then. Make sure you make plans to be at our Fall convention in Amana, Ia. Teri and I just planned our route up hiway 61 tonight. You can jump behind us and follow if you wish.
I am on the blacklist. Here is my cell number, write it down.
573-six 25-ten 38.
And, you are welcome to drive 20 miles west on 60 to park in our driveway free. That would be great.
Dan


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: I Need Advice about Air Bag System Leaks [message #159783 is a reply to message #159781] Thu, 09 February 2012 18:28 Go to previous messageGo to next message
jaholland is currently offline  jaholland   United States
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BesB;

Call Jim B at gmccoop.com
Get And Install The Air Bag Cut Off Kit {$55.00}

Fill your air bags and set the cut off switch and
when you get to a GMC Rally Or To A Seasoned Owner
We will Help You Find Your Leak ~

~ Joe ~

{ There's always a lot of hot air at the rallys }


/_]*[__][] *[__|] ~ * '73 TZE063V101887 "
" O----------OO--]* ~ '78 TZE168V100234 "
" " Joe & Lavelle " "
" 'sweet home alebamy'

[Updated on: Thu, 09 February 2012 18:30]

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Re: I Need Advice about Air Bag System Leaks [message #159806 is a reply to message #159724] Thu, 09 February 2012 20:48 Go to previous messageGo to next message
Luvn737s is currently offline  Luvn737s   United States
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For finding leaks, I'd use some glycerine or the stuff kids blow bubbles with (not gum!). It's mostly glycerine. The bubbles will show up better than just soapy water. You don't have to have much mechanical ability to dribble a little glycerine around where air lines connect. At least you could direct someone to the right general area, whether its a repair shop or a helpful GMCer. Plus you'd feel more confident knowing where the problem might be.

My GMC has a receiver hitch and I will place a jackstand under it to act as a "tail stand" of sorts in case it goes down too far.

The cut-offs are a great idea and can isolate a problem and give you peace of mind, which is what keeps owning a GMC fun.


Randy
1973 26' Painted Desert
Ahwatukee (Phoenix) AZ
Re: I Need Advice about Air Bag System Leaks [message #159824 is a reply to message #159806] Thu, 09 February 2012 23:01 Go to previous messageGo to next message
Ken Burton is currently offline  Ken Burton   United States
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If you have a 1976 GMC with the compressor inside in the rear then you have an ELECTRO-LEVEL I AIR SYSTEM. You do NOT have the power valves that leak that someone mentioned in previous posting. The power valves would be located in place of the toggle switches that you have on you dash near you right knee.

Please take Dan up on him offer to look at your coach. He is just west of Sikeston.


Go here for a good presentation on the air system:

http://gmcws.org/Tech/dsimmons/air_suspension/air-suspension-system.html

Print it out and take it to whomever you are using to fix your problems. Tell them to look at the Electro level I section.

The air system has basically tree isolated sections at rest with the power off. The air pressure for the left bag, the air pressure for the right bag, and the stored air pressure in the tank. These are not connected together when the power is off.

I would trouble shoot each at these three separately with the power off. If the bags themselves are not leaking, then almost all of the time the problems with the bag staying up are with the hose connections. The original connections were plastic and now leak 30 years later. Replacement brass connections are around $3.00 each. They are simple to replace and there are about 12 of them total. When I replaced all of mine years ago they were about $1.50 each and it took care of all of my air leakage problems.

Granted there are other things that can leak but the fittings are where I would start.

If it is taking 15 minutes to pump up the bags then your pump is tired. You can rebuild or replace the pump but I would not bother with that until I got the leaks fixed. With the leaks gone the pump will seldom need to run.


Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
Re: I Need Advice about Air Bag System Leaks [message #159951 is a reply to message #159824] Fri, 10 February 2012 21:29 Go to previous messageGo to next message
bess is currently offline  bess   United States
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Hi Ken, Thank You for the Link and I printed it out. The Compressor didn't work this hard before I got her "fixed". It use to come on a few minutes and you would have to really listen to tell it was running. Now, you can't miss the noise, and she runs forever. I Definitely would Welcome Dans Help or Any Help I can Get. It seems like things are getting Worse. I know that when they tried to fix the leaks - they unhooked the GMC's Compressor and connected their Compressor up to the Motorhome to try to find Leaks and said that they found 5 leaks in the fittings and they fixed them. I sure was hoping that this problem was fixed - but no such Luck. As soon as it gets warmer - I definitely want to get her so she doesn't "sink" when she is setting.

Bess Brenenstall Elvaston, Illinois 1976 Birchaven
Re: I Need Advice about Air Bag System Leaks [message #159956 is a reply to message #159951] Fri, 10 February 2012 21:51 Go to previous messageGo to previous message
Bob de Kruyff   United States
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Location: Chandler, AZ
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bess wrote on Fri, 10 February 2012 20:29

Hi Ken, Thank You for the Link and I printed it out. The Compressor didn't work this hard before I got her "fixed". It use to come on a few minutes and you would have to really listen to tell it was running. Now, you can't miss the noise, and she runs forever. I Definitely would Welcome Dans Help or Any Help I can Get. It seems like things are getting Worse. I know that when they tried to fix the leaks - they unhooked the GMC's Compressor and connected their Compressor up to the Motorhome to try to find Leaks and said that they found 5 leaks in the fittings and they fixed them. I sure was hoping that this problem was fixed - but no such Luck. As soon as it gets warmer - I definitely want to get her so she doesn't "sink" when she is setting.



Bess, it doesn't take much to make the coach sag because there isn't much volume of air involved. It's quite possible that the folks who repaired your system did actually find several leaks. I wanted to assure you that this is not a serious issue and many GMC'rs tackle this all the time. It shouldn't keep you from doing whatever you want to do with your coach and it's unlikely that you will hurt anything by using and enjoying it. You will meet a lot of folks who can start to pinpoint some specific areas.


Bob de Kruyff
78 Eleganza
Chandler, AZ
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