Another Ride Height Question

[Bill C]

Both the Left and Right sides of my rear ride height system stopped working a few weeks ago. I finally had a chance to look at the control valves and found that they "T" (see pic) that connects both the left and right side leveling valves are leaking air where the "T" connects to the brass fitting that screws in to the connection going to the air tank.  I have a 10 air bag system on my 2001 Monaco Dynasty 40 Queen.

My questions are:

1. When I disconnect this "T" to replace it, the air in the ride height air bags will drop to zero, but do I have a separate air system for my HWH air bag leveling system than what is used for my air ride leveling system? If so, my air leveling system can keep the coach up while replacing the "T". I am concerned that the coach will drop down all the way  down and make it hard for me to get out from under the coach until the "T" is replaced and the RV is started and air is pumped in the ride height system again.  I suspect I can put some sort of block between the main rails and the frame, but that seems like a lot of weight to hold up, what would be strong enough and big enough?

2. What is this "T" called and where can I purchase one (what type of store)?

 

Thanks,

Bill

[ncsteve]

Those are push to connect air line fittings. Need to make sure you get the D.O.T. Approved brass ones. 
some Napa stores carry them as well as truck service centers. Also McMaster Carr sells them. 
https://www.mcmaster.com/push-to-connect-tee-connectors/shape~tee/low-temperature-d-o-t-push-to-connect-tube-fittings-for-air-8/

from my experience, you will have to drain all air. Do not do it while under the coach. I made some ramps to drive on that gives me enough room to get under there once it is aired down. You can block the frame as well, but make sure if you do, it can handle the weight.

[John Haggard]

Hello Bill

I read through all of your questions, they are all Viable and important questions.

My take is.

 

Get the rig into a big rig truck repaire shop and let them do the job.

They have the equipment,  the parts, and safety equipment to get your job done efficiently and safely. 

 

[Bill C]

Thanks for the info Steve B

7 minutes ago, ncsteve said:

Those are push to connect air line fittings. Need to make sure you get the D.O.T. Approved brass ones. 
some Napa stores carry them as well as truck service centers. Also McMaster Carr sells them. 
https://www.mcmaster.com/push-to-connect-tee-connectors/shape~tee/low-temperature-d-o-t-push-to-connect-tube-fittings-for-air-8/

from my experience, you will have to drain all air. Do not do it while under the coach. I made some ramps to drive on that gives me enough room to get under there once it is aired down. You can block the frame as well, but make sure if you do, it can handle the weight.

Thanks Steve B

[Hypoxia]

When you disconnect the hose from the fitting, cut about 1/4" off of the hose and clean it to insure the new fitting doesn't leak.  There will be an indentation in the hose from the old fitting.  I block the frame with pipe that has at least 1/4" wall thickness.

[Guest Ray Davis]

Bill,  You have a simple repair but in a dangerous place.  You just can't afford to gamble with blocking etc.  Ramps made from 2x12s stacked are a good way to go then let the coach down before getting under it.

[Bill C]

2 hours ago, Hypoxia said:

Good info, thanks

Bill

[walt2137]

Bill run the rear wheels up on a couple 12x12 deplete the air in the system use a 1/4 or 10 mm open end wrench and small hammer (with a little WD40) to push the little rings in and remove the plastic tubing and replace if needed with DOT tubing at NAPA. It is a simple fix no reason most could not do the repair. 
 

Walt

[Bill C]

Good info Walter, thanks

Good info Walter thank you.

[dl_racing427]

Bill, 

For God's sake NEVER EVER get under a coach that is supported by its air suspension OR by hydraulic leveling jacks. 

ANY failure in those systems WILL suddenly drop the coach to within a few inches of the ground. 

Get truck jack stands rated for the load and USE them. 

I don't want to read another story from an owners widow about this. 😢

As far as replacing the fitting, it's easy once you dump the air. Use an open end wrench to depress the ring and the hose should pull right out.  Cut off 1/4" of the hose, wipe it clean and install a new DOT T fitting. 

[Bill C]

Good info, thanks David

[Bill C]

After replacing the T air fitting the problem was not resolved. It doesn’t seem to be an air leak as best I can tell. I feel like it might be electrical since neither air valve is working. I took it to the shop and they’re chasing their tail saying it’s both air valves. I find it hard to believe that both air valves would fail at the same time. Is there a fuse or something electrical  for the ride height airbags?

[Guest Ray Davis]

 Bill,  Air leveling systems are complicated but if you want to read through this document you may be able to diagnose the system.

  https://www.hwhcorp.com/ml57000-018.pdf

 Tell us a little more about how your system acts.   You said the right & left rear ride height stopped working, explain that some more.

[Bill C]

More Explanation: It seems like for the last couple of years my ride height was getting lower. I just assumed it was because my hydrolift and gold wing motorcycle were mounted on the back of my RV (I do have a tag axle), however I don't recall it sitting lower when I first installed the HL and GW on the back 4-5 years ago. About one month ago I notice when I was pulling out for a trip that the back end was so low that the rock shield was dragging the ground. I was not sure of the problem, but since I was leaving on a 2-week trip I just raised the rear of the RV using my leveling system. Everything seemed to be working fine driving down the road, but I suspect it was because I raised the ride height using the leveling system air bags. Every time I got ready to leave my camp site, while on this trip, I did as I usually do, turned the HWH leveling system off but the rear of the coach would never raise at all unless I used the HWH system to manually level it. As I recall, neither the driver’s side, nor passenger side raised in the rear (without manually raising them) so I believe the issue is common to both ride height air bags. I got under the rig and I did find a "T" shaped air splitter leaking air so I replaced it (DOT approved from NAPA). I thought the “T” splitter was for the ride height air bags and that once I replaced it all would be good. However, while replacing it I noticed that it was actually not part of the ride height air bag system, and was disappointed it did not solve my problem. Upon further inspection, looking for leaks (found none), and tracing the ride height system I realized that I needed to take it to the shop for the experts help. It has been at the shop since Wed (4-5 days) and all they have been able to tell me is that the ride height valves are adjusted all the way up (I tried to adjust one early on in my trouble shooting). I asked them: well, is the ride height system working, and they told me "we don't know, we didn't test it". I was very frustrated and had some words with them about my concern that the tech working on it is not too qualified. The shop assured me that he was and that he works on these all the time.

A couple days later I called them to get an update and was told that the tech said we needed two valves, that both had failed. I told the service manager I found it hard to believe that both valves failed at the same time, but that they were the experts so I said "OK but if you replace both of them and it did not solve the problem, I did not want to be charged for the replacement." The service manager started thinking I was probably right, it would be unusual for both to fail at the same time, so he was going to go back to the tech and discuss it some more. It has been a couple more days now and they called me last night to tell me that the tech had been working on it but has not found the problem yet, but that they had to move the tech to another job that came in before me and would work on it again on Monday, 2 days later.

I hope this "further explanation" helps. I am wondering if it could just be a fuse somewhere?

One more thing: I have a 8 air bag system (4 front and 4 rear). I can't remember which.

Thanks,

Bill

 

Edited January 31, 2021 by Corkman

[John Haggard]

Sorry your having such a frustrating time. 

 

Two questions.

1. What is the current pressure setting for your tag axle ?

Did you adjuste the pressure ? Increase it when you added the bike lift. ?

2. Is your HWH system working 100 %

Correctly now.

I see that you can lift the rear end and travel.

After you lift it to ride height. And go down the road does the green travel light come on.

 

 

[Guest Ray Davis]

Yes very good explanation.  My uneducated guess is that the proper signal is not being sent to the valves on the 6 pack manifold that sends air through the ride height     valves.  The ride height valves then control the air bags.    It could be a fuse, I believe there are fuses in the control box.  That's where the tech should start looking.             If you can why, not print the PDF link in my previous post and give it to the tech.  You could study it your self and perhaps shoe him the areas you think should be     checked.

 Here is another site where you may find some help It's about Foretravel coaches but the HWH air level system is very similar.

 Foretravel Motorhome HWH: Emergency Leveling Valve Override Procedure | All Things Foretravel

[Bill C]

37 minutes ago, John Haggard said:

See comments below, BTW it's in the shop so I can't really do much at the moment.

Sorry your having such a frustrating time. 

 

Two questions.

1. What is the current pressure setting for your tag axle ? - Not sure, where could I find out?

Did you adjuste the pressure ? Increase it when you added the bike lift. ? - No

2. Is your HWH system working 100 %

Correctly now. - As best I can tell, yes

I see that you can lift the rear end and travel.

After you lift it to ride height. And go down the road does the green travel light come on. - Green light is one even when the ride height is too low

 

 

 

I just came back from talking to the service manager. It sounds like their tech and service manager are working together and making smarter decisions.

I was told that they have checked the fuses, and also found that only one of the front ride leveling air bags is working.

I suggested that they remove the panel where the HWH controls are and make sure all the connections are connected. In the past, one or two times, the connections on this HWH control panel have worked themselves lose, due to bumps in the road and gravity trying to pull them off (down toward the road). Here will have that checked.

[David Pratt]

 

The HWH leveling system is totally independent of the ride height control valves to put the coach in ride height for traveling. The ride height control valves play no part in the auto leveling of the coach. When you put the coach in Auto Level, the ride height control valves are taken out of the system and the coach is leveled by signals from the HWH ECM to the Six Pak Valves that are located in the chassis above each axle. The Six Pak Valves are also taken out of the Loop when your coach is in Travel Mode and only the three ride height control valves control the ride height of the coach. The HWH Auto Leveling System when put into the Manual Mode will allow you to raise or lower the coach up or down a few inches, but as soon as you start moving and exceed 5MPH the coach will automatically revert back to Ride Height and the HWH System. Regardless of what Mode you have the HWH Auto Leveling in, when you release the park brake and put the coach in gear it automatically reverts to ride height, This is the automatic default for the coach. This also takes the HWH System out of the loop.

Make sure the ride height is set correctly on the steer axle and the drive axle and that you are using the correct pressure setting on the regulator for the tag axle for the additional weight of the M/C lift. Those M/C Lifts add a lot of weight to the rear axle of the coach because of the moment from the rear axle to the lift. If you have not done so you should have the coach weighed with the motorcycle on the lift and adjust the Tag Axle Pressure accordingly.

[rpasetto]

Bill, This picture below may help explain things.  When your HWH system is in leveling mode, the four "raise/lower" valves control air to the air bags in each axle position; the travel valves are closed so not air gets to the valves through the ride height valves.  When in "Travel mode"  the travel valves open to allow air to pass to the air bags via the one ride height valve in front, the two ride height valves for the drive axle and the tag axle regulator. For example, the left travel valve feeds air to the 2 left airbags via the left ride Ht valve, the right travel valve feeds air to the 2 right airbags via the right ride Ht valve.  In front the both travel valves connect thru one ride height valve to feed all four of the airbags. 

That is, if everything is working correctly.  When you are driving, in Travel mode, if the travel valves do not open properly there is nothing the ride height valves can do to get air to the bags, even with the green travel light on.  So one thing that needs to be checked is that the valves on the 6-pack are opening and closing properly; valves can stick in either position, or the solenoid can go bad, or the wrong electrical signal can be getting to some of the solenoids.   Once you are sure the 6 pack valves are working like they should in travel mode the ride height valves can be checked.  Hope this helps.

[Bill C]

17 hours ago, rpasetto said:

Very good info, thanks for Sharing.

Bill

 

 

[Guest Ray Davis]

 Yeah,  separate systems but not totally independent.

 If you look at Rick's drawing you'll see 2 travel solenoid valves on each manifold.  That's 6 travel solenoids if you have a tag axel.

 The control box tells those valves to open letting the ride height ( travel ) valves take control of the air bags.

 A missing signal, a bad, or stuck solenoid valve can cause havoc 

[rpasetto]

Ray's post made me think of a way to check to see if the problem is the control box signal to the travel solenoids.  After checking all fuses and making the necessary disconnections you can jumper 12v to the wire(s) which send the travel signal.  Start engine and if all airbags comes up  properly the signal is the problem.  I recall having to do this a year+ ago when I removed the control box to send to HWH for repair.

[Guest Ray Davis]

3 hours ago, rpasetto said:

Ray's post made me think of a way to check to see if the problem is the control box signal to the travel solenoids.  After checking all fuses and making the necessary disconnections you can jumper 12v to the wire(s) which send the travel signal.  Start engine and if all airbags comes up  properly the signal is the problem.  I recall having to do this a year+ ago when I removed the control box to send to HWH for repair.

 Rick's plan sounds good but I believe in the rear you should jumper both solenoids.   You don't want one corner to rise up too much for fear   of   twisting the coach.

Edited February 2, 2021 by Ray Davis

[Bill C]

3 hours ago, rpasetto said:

Good idea

 

[rpasetto]

3 hours ago, Ray Davis said:

 Rick's plan sounds good but I believe in the rear you should jumper both solenoids.   You don't want one corner to rise up too much for fear   of   twisting the coach.

I don't recall exactly but in the middle bay where the HWH 'brain' was mounted, it had one or two connections labelled for "travel" mode.  That's why I had said wire(s) 🙂

I recall laying in the bay looking up at the HWH box, disconnecting it and labelling all the wires while Bill (Hotrod) was explaining to me what to do, using the signal from one of the wires which was 'hot" when the key was on.  IIRC, HWH charged me around $100 to repair the box... still easier than getting under coach to change a valve or two on a six pack.