Air bags lose air

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Air bags lose air

May 05, 2023, 01:37:39 am

For some time now, my FT driver side rear air bags have been losing air when left in park/travel mode or parked without the safety spacer. I have attached two pictures for reference. When I raise the coach fully and leave it in that position (not in auto level or park/travel mode), all the other corners (air bags) stay full and do not lose any air. However, the driver side rear air bag loses air until the safety spacer is in place / reached, and once it is, there is no more air loss and the bag stays stiff. Without the spacer, the weight of the coach pushes the air out slowly, causing the air bags to become depleted.

The front 6-pack has been rebuilt, but the rear has not. About 6 years ago, during a visit to FT service, I had this issue looked at, and I believe they replaced one of the solenoids (I came home and discovered that it was not fixed.) Should I raise the vehicle and perform the soap water test, or should I rebuild the rear 6-pack? Ideally, I would like to just fix this issue and not get in to rear 6 pack rebuild project right now.
Thank you,
Al

Re: Air bags lose air

Reply #1 – May 05, 2023, 08:05:57 am

Good Morning Al,

I'd probably start at the "root" of the problem, and work upstream from there. With coach raised fully (safety stands in place), soap test the bags, the fittings on top of the bags, and the air lines going to the bags. If no leaks found, that leads you to the 6-pack. Next logical step is rebuild. Sorry 'bout that.

Re: Air bags lose air

Reply #2 – May 05, 2023, 08:49:09 am

My air line schematic plan shows that each pair of airbags at each corner of the coach T together outside of the six pack. Of course that's not the case because each air bag has a separate air line connected to the six pack however schematically they do T together within the six pack manifold because there is only one raise and one lower solenoid per corner. It seems to me that with this arrangement both air bags would always be at the same pressure and that a leak in one air bag or the other would affect both. Am I missing something?

Re: Air bags lose air

Reply #3 – May 05, 2023, 09:14:34 am

No you're correct. Yes checking the lines and bags won't hurt, but probably all roads (connection) head back towards the six pack. Illuminate the external leaks then go to the internal bypassing

Re: Air bags lose air

Reply #4 – May 05, 2023, 09:17:41 am

Quote from: Geodmann – May 05, 2023, 08:49:09 am

It seems to me that with this arrangement both air bags would always be at the same pressure and that a leak in one air bag or the other would affect both. Am I missing something?

No, you are correct. I should have worded my question better. I was just trying to get at the fact that the air leak could be in one single bag, which would, as you say, also reduce the pressure in the other bag in that pair. I will delete that line in my post.

I suppose there could be some bizarre situation of trash plugging up the internal passages in the 6-pack which would allow one bag to go flat while the other held pressure. Stranger things have probably happened...

Re: Air bags lose air

Reply #5 – May 05, 2023, 09:33:00 am

Firm doesn't mean at pressure to support. Doubtful they are at different pressure and would have all sorts of other weird stuff if plugged. You have an air leak/loss or a six pack bypassing internally. What do your air tanks pressure do?

Re: Air bags lose air

Reply #6 – May 05, 2023, 10:57:36 am

All good advice above. From personal experience I had always used dawn soap and water to spray and look for leaks. I have learned the hard way is that is not real good for finding air leaks and was told to use kid bubbles, which I now use. Also spray the 6 pack down good to see if a leak shows up. There are two spots a valve can have an external leak. Around the surface between the valve and plate and at the valve just below where the coil is resting at the base of the valve. If you find no leaks than there is a good chance that one of valves in the 6 pack is leaking internal. There are a few steps to be able to tell if it is the raise or lower valve that is leaking. If your system has an aux air pump for the HWH system, and it is holding pressure on the air tanks, then the leak is in the exhaust valve.

Re: Air bags lose air

Reply #7 – May 05, 2023, 11:58:03 am

I found the kiddie bubbles to be hit or miss. Some worked well others did not. I also found it hard to source locally... I guess kids don't use it these days. Either way, the best stuff I found was this: Amazon.com: Heavy-Duty Leak Detection Fluid Concentrate makes one gallon,...

Works very well and "clings" longer than soap/bubble solution. Helped me find a few pesky, very hard to find leaks.

If your rear six pack is still original, you might as well do the rebuild. If it's not the problem right now, it will be soon.

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.

Re: Air bags lose air

Reply #8 – May 05, 2023, 12:56:08 pm

Elliot have you tried this product. This came up while I was looking at your Amazon link.

Amazon.com: Ken-Tool Detecto Mist Concentrated Leak Locator (35805) : Automotive

Michelle,
I might have missed it but did not see "Foreforum" in Elliot's link address. I used the Foreforum link then looked at the product moved around in Amazon, I then came up with this item and copied the page link. Am I doing something wrong?

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Re: Air bags lose air

Reply #9 – May 05, 2023, 12:58:34 pm

Quote from: turbojack – May 05, 2023, 12:56:08 pm

Elliot have you tried this product. This came up while I was looking at your Amazon link.

Amazon.com: Ken-Tool Detecto Mist Concentrated Leak Locator (35805) : Automotive

I have not. One bottle of that concentrate I linked to should last long enough to find all your leaks. I still have over half a bottle after many, many hours of leak hunting.

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Re: Air bags lose air

Reply #10 – May 05, 2023, 01:04:17 pm

Quote from: turbojack – May 05, 2023, 12:56:08 pm

Michelle,
I might have missed it but did not see "Foreforum" in Elliot's link address. I used the Foreforum link then looked at the product moved around in Amazon, I then came up with this item and copied the page link. Am I doing something wrong?

I'm seeing "foreforums" if I click both Elliott's and your links (also if I hover over and wait a sec for the link in the post to resolve).

Re: Air bags lose air

Reply #11 – May 05, 2023, 01:26:44 pm

Quote from: Michelle – May 05, 2023, 01:04:17 pm

I'm seeing "foreforums" if I click both Elliott's and your links (also if I hover over and wait a sec for the link in the post to resolve).

I tried that and saw "foreforums". Not sure what I was doing before.

Re: Air bags lose air

Reply #12 – May 05, 2023, 02:09:07 pm

Quote from: Chuck & Jeannie – May 05, 2023, 08:05:57 am

Good Morning Al,

I'd probably start at the "root" of the problem, and work upstream from there. With coach raised fully (safety stands in place), soap test the bags, the fittings on top of the bags, and the air lines going to the bags. If no leaks found, that leads you to the 6-pack. Next logical step is rebuild. Sorry 'bout that.

I don't know why, but I have been dragging my feet on the rear 6-pack. The front was easy, but the rear one is located forward of the differential, and although not too bad, it looks a bit tight for my slight claustrophobic self. Chuck :-) you know, you could just come up and supervise

The AC will be on, and we will fire up the grill to cook some fresh catch from Lake Texoma.

Re: Air bags lose air

Reply #13 – May 05, 2023, 02:24:49 pm

Sorry - wish we could help, but our at-home list of projects is already overwhelming. Right now we are madly searching for a new complete A/C (heat pump) system for the house. The old one is on life support and threatens to pass away any time.

But I will be there in spirit when you bite the bullet and slide under your coach!

Re: Air bags lose air

Reply #14 – May 06, 2023, 11:50:28 am

If I couldn't find a leak I would start swapping solenoids to see if the problem moves to the other side.
I would start with the dump solenoid.

Re: Air bags lose air

Reply #15 – May 06, 2023, 04:30:08 pm

I'm close, NAC, but unable to help.

Re: Air bags lose air

Reply #16 – May 06, 2023, 04:36:26 pm

You have two rear leveling valves on your coach there next to the air bag with two air lines coming off it and an adjustment rod . It sounds to me like the leveling valve on the rear driver side is neither out of adjustment or is leaking. They level the coach while you are driving or in motion they are part of the suspension . I would suggest changing the leveling valve on the rear driver side and beware there are two different types of leveling valve fast reacting, and delayed reacting .I believe I change all three on mine one in the front and two in the rear and I install the fast acting. Part number 90555105 $125.00 Canadian each the reason I'm thinking it's a chassis leveling valve is because Foretravel has already played around with the six pack and you have the same problem . It's an easy change for probably a $100.00 us valve try soap and water and listening for any air leaking from this valve. It is a levelling valve. You will hear air leaking from it till it levels itself off then stop.

Re: Air bags lose air

Reply #17 – May 06, 2023, 06:47:28 pm

Quote from: Cape Bretoner – May 06, 2023, 04:36:26 pm

You have two rear leveling valves on your coach there next to the air bag with two air lines coming off it and an adjustment rod . It sounds to me like the leveling valve on the rear driver side is neither out of adjustment or is leaking. They level the coach while you are driving or in motion they are part of the suspension .

Propman is having trouble when he's parked, not going down the road. I don't believe the ride height valves (the leveling valves with rods you mention) are controlling the coach height in that circumstance.

Quote from: propman – May 05, 2023, 01:37:39 am

When I raise the coach fully and leave it in that position (not in auto level or park/travel mode), all the other corners (air bags) stay full and do not lose any air. However, the driver side rear air bag loses air until the safety spacer is in place / reached, and once it is, there is no more air loss and the bag stays stiff. Without the spacer, the weight of the coach pushes the air out slowly, causing the air bags to become depleted.

Re: Air bags lose air

Reply #18 – May 06, 2023, 08:06:53 pm

I had an air valve in the back right hand side with the coach sitting there was air leaking out the exhaust port all the time so I replaced the three of them they were 21 years old I was just thinking if the seals are old and dried up it maybe were it's losing air Just something to check before removing the six pack since Foretravel had already changed a valve on the six pack. I presume it was that side they changed just a thought.I've been under looking up at the six packs many times, looking at all the air lines and trying to figure out the configuration where all this air systems are passing. There is only one air line going to each air bag and at least two systems and maybe three filling each airbag. travel mode, leveling mode, and manually rise and lowering mode ? He's having problems if I understand right with Manually mode he raises the coach, and then turns the key off, and then he loses air in the one airbag not in leveling mode or travel mode which the air compressor would keep it supplied with air. In leveling mode the 12 volt compressor will keep it up .my coach if rises it manually and turn the key off it takes about two weeks I will lose air in the back airbags, but the front will stay raised for ever and I can not find the leak it takes over two weeks to lose it just the back .l I believe the air passes through these leveling valve in all three modes. There is only one line going to the airbag, and it comes off the levelling valve.trying to understand the system myself

Re: Air bags lose air

Reply #19 – May 06, 2023, 09:53:55 pm

Quote from: Cape Bretoner – May 06, 2023, 08:06:53 pm

There is only one line going to the airbag, and it comes off the levelling valve.trying to understand the system myself

This line from the any air bag should go straight to the 6 pack and then the ports through the 6 pack deliver air through the ride height valve. Double check your B 2193 air line print to be sure.

Mike

Re: Air bags lose air

Reply #20 – May 06, 2023, 10:40:21 pm

X2 what Mike says:

Re: Air bags lose air

Reply #21 – May 07, 2023, 08:59:30 am

Quote from: Cape Bretoner – May 06, 2023, 08:06:53 pm

I've been under looking up at the six packs many times, looking at all the air lines and trying to figure out the configuration where all this air systems are passing. Trying to understand the system myself.

Rick (and any of our newer Forum members),

The leveling system IS kinda hard to figure out. I've been messing with our coach for over 10 years and it still seems confusing at times - especially when chasing never-ending and elusive leaks. Getting under the coach and studying the air line routing is a valuable exercise (both mental and physical) but you still need good diagrams to help to understand the big picture. Luckily, HWH has provided some excellent resources. The three links below will be a big help - at least they were to me.

https://hwhcorp.com/ml11148.pdf

https://www.hwhcorp.com/ml20635.pdf

ONLINE SCHOOLS – HWH® Corporation

Re: Air bags lose air

Reply #22 – May 07, 2023, 11:44:23 am

This system isn't very complicated.
There are two systems here.
Travel and leveling. Only one can be working at a time.
Travel is only working when the green travel light is on. Then the travel (top two) solenoids are powered open allowing the ride height control valve to let air in or out of the bags.
That's it.
The level system lets air in (bottom two) through the raise solenoids, and air out through the (middle two) dump solenoids.
The computer ( with information from the level sensor in the coach) now takes the place of the ride height control valve to let air in or out of a bag by actuating a raise or dump solenoid.
That's it.
Look at your problem and what mode (travel or level) your are in to solve what is not working to correct the problem.
It can get complicated if there is more than one thing wrong.
Think it through and you will fix the problem.

Re: Air bags lose air

Reply #23 – May 08, 2023, 10:11:48 am

Can anyone here confirm the fitting thread size into the HWH six packs? I'm chasing some leaks of my own and I would like to order an assortment of fittings today but I'm not home to check this myself. I assume it's 1/4"npt x 3/8 od tube but I want to be sure before I place the order. Thanks

Re: Air bags lose air

Reply #24 – May 08, 2023, 11:17:53 am

Quote from: Geodmann – May 08, 2023, 10:11:48 am

Can anyone here confirm the fitting thread size into the HWH six packs? I assume it's 1/4"npt x 3/8 od tube...

I won't guarantee they are the same size on EVERY 6-pack, but the link below (to Reply #33) lists the parts I used to rebuild my manifold. Note that I found two different threads on my manifold air line connectors.

Working On My Six Pack

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