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Topic: Corner leveling problem while driving.  (Read 1081 times) previous topic - next topic

Corner leveling problem while driving.

I'm having a problem with the RF corner being lower than the other corners while driving. When parked, the RF is lower then, too.  Those 2 airbags are noticeably soft.
All airbags are less than a year old. No service has been done to the HWH since I've owned it - 2 years. About 2 months ago I adjusted each of the rear levelers to set them at 8.5".
The rear corners measure 8.5"  from flange to flange while the LF is too tall and the RF measures just 5.5".
The dash warning light and alarm goes off after just a 1/2 mile or so. I can manually inflate the RF while driving. I can hear air escaping as soon as I release the button to inflate it.
I soap-tested both 6 packs, the air hoses to each airbag, and the 3 valves with gauges (1 on each tank and a third at the step). No leaks.
When parked, the top dash-mounted air gauge leaks to zero much faster than the lower dash air psi gauge. Hopefully, that's a clue to the source of the problem.

I welcome a diagnostic checklist to solve it.
Steven
1997 U320 40'  Orlando, FL
"Purple Haze" which will soon be for sale.... !

Re: Corner leveling problem while driving.

Reply #1 –
New airbags do not insure no leaks in the bags. Rubber is very soft for the most part when it's new. My experience is it gets tougher as it ages.
Old Phart Phred, EIEIO
89 GV ored 36' #3405 300 hp cat 3208 ATAAC side radiator, mountain tamer exhaust brake

Re: Corner leveling problem while driving.

Reply #2 –
If the RF air springs (bags) are soft you definitely have a leak somewhere.  Time to get out a spray bottle of soapy water and try to find it.  There are 2 leveling valves one each side in the rear and only one in front for both sides.  You will probably have to go under the coach so be sure to put safety supports between the frame members first so the coach doesn't come down and crush you.  I would raise it up first and spray the bags and hose connections. 
Jerry Whiteaker former owner 96 U270  36' #4831 Austin,TX-Owner Mods LCD TV w/front cabinet rebuild - LCD TV bedroom - Dual Central AC, either can cool coach w 30 amp - Skylights at roof AC openings - Drop ceiling for ducting of AC - Shower skylight white gelcoat/wood/epoxy frame - Air Springs/Shocks replaced - 2014 CRV - 8K Home Solar - Chevy Volt

Re: Corner leveling problem while driving.

Reply #3 –
Quote
I'm having a problem with the RF corner being lower than the other corners while driving.

Is the Travel light illuminated on your touch pad? If not, maybe your right front Travel solenoid is the problem. The front six pack manifold has two Travel solenoids, one for left and one for right. I had that problem last year. In order to drive it safely, I leveled it manually and then removed the Travel fuse from the HWH box. When you do that, it will stay at that level indefinitely.

Lots of experts here on the system so I suspect you'll get the help you need soon.
jor
93 225
95 300
97 270
99 320

Re: Corner leveling problem while driving.

Reply #4 –
You do need to solve this problem before you drive it or you might break a windshield.
John Duld
1995 U320C SE 40'

Re: Corner leveling problem while driving.

Reply #5 –
Yes, the green travel light will illuminate for a short period of time before the RF drops down.

I'll soap suds the hoses and front bags again.

Why would the LF be higher than the 8.5" that it was set ? With only ONE leveling valve shared between the 2 front corners, why is one side lower?

I found and solved a  leak under the dash gauge cluster. I installed fresh thread tape and tightened an air fitting. 

What items are associated with the top, not the bottom, air gauge on my dash?

1997 U320 40'  Orlando, FL
"Purple Haze" which will soon be for sale.... !

Re: Corner leveling problem while driving.

Reply #6 –
If both rears are set at 8.5 and the RF is 5.5 and the LF is higher, the coach is twisting. When you get the RF correct the LF will take care of itself. Left to right is controlled only by the rear air bags.
1999 40 ft. U-320 wtfe build 5563 Chuck & Lynda's "Rollin' Inn"  2030 watts solar
prev. mh's 71 GMC 5 yrs. 73 Pace Setter 1 yr. 78 Vogue 5 yrs 81 FTX 40ft all electric 18 yrs. 1996 Monaco Signature 3 yrs.
2014 Grand Cherokee Overland
Dream as if you will live forever. Live as if you will die today.  James Dean

Re: Corner leveling problem while driving.

Reply #7 –
Quote from: StevenOrlando –
Yes, the green travel light will illuminate for a short period of time before the RF drops down.

I'll soap suds the hoses and front bags again.

Why would the LF be higher than the 8.5" that it was set ? With only ONE leveling valve shared between the 2 front corners, why is one side lower?

Steven,
This sounds like you have a lower solenoid on the front 6 pack that has stuck open.  (trash or mud dauber nest) If open when the air pressure gets low enough the travel light will go out as all it is for is to tell you that you have air pressure.  If the a solenoid is failed open you are exhausting through the exhaust port in the valve block. This is hid behind the pressure switch sensor on the 6 pack. (mud/dirt daubers can still find this little hole)

One side could be lower because it is exhausting while the other side is trying to raise up to achieve proper ride height.  As stated in an above post, if this is the case you are twisting the front end and this needs to be addressed before you crack a windshield.

Pamela & Mike
Pamela & Mike 97 U 320

"It's not what happens to you, but how you react to it that matters."

Re: Corner leveling problem while driving.

Reply #8 –
As others have said your problem is in the HWH solenoids for the front, not the ride height valves or airbags.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: Corner leveling problem while driving.

Reply #9 –
I had this issue this winter when down south. Yes, be careful, I ended up with a split windshield,doing what you were doing, driving while Manuel raising it. It was broke anyway.
Mine was the left bags, but it took replacing the Right side travel solenoid. Don't ask me why, it even stumped Aubrey at FT. I have since double and triple checked the wire colors and air lines.
They are easy to check with a simple test.You can activate them with a screw gun battery and 2 jumper wires, you will hear them "click". You can also check the voltage at the solenoid. Unplug it, then have someone turns the key on.
CAUTION.....Make sure the coach is blocked up, and dump the air tanks,before you pull any valves out.
Chris

I get new valves here. Same price as HWH, quicker.Nice people, quick service:

Replacement HWH Air Solenoid RAP1940: nwrvsupply.com
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348

Re: Corner leveling problem while driving.

Reply #10 –
There are two modes in this system
Travel mode and level mode.
Only one can work at a time.
Travel isn't working but is it the travel mode or is the level mode leaking the air overboard that the travel mode needs to hold the coach at travel height?
Can you raise and level the coach in the level mode?will it stay there?
If not you need to fix that leak first.
Maybe swap the dump solenoids to see how that affects the system.
You'll find it, a leak this big can't hide!
John Duld
1995 U320C SE 40'

Re: Corner leveling problem while driving.

Reply #11 –
John,
I can raise/lower the coach in 'level mode'. It will hold pressure for days. The top dash gauge will fall to 0 but the coach remains level. As soon as I enter 'travel mode', the coach will lose pressure on the RF.
I cleaned the 2 exhaust ports today. They were not blocked, no signs of debris in them.

Regarding the 'twisting' notion, the front tires are within 3psi of each other - 109 and 112 cold.
The fuel tank is nearly full, no excess weighty items anywhere in the coach.

I played with the front ride height valve and it operates as expected - raising and lowering the front axle by extending/shorting the rod length between the rubber ends.
1997 U320 40'  Orlando, FL
"Purple Haze" which will soon be for sale.... !

Re: Corner leveling problem while driving.

Reply #12 –
Quote from: StevenOrlando –
John,
I can raise/lower the coach in 'level mode'. It will hold pressure for days. The top dash gauge will fall to 0 but the coach remains level. As soon as I enter 'travel mode', the coach will lose pressure on the RF.
I cleaned the 2 exhaust ports today. They were not blocked, no signs of debris in them.

Regarding the 'twisting' notion, the front tires are within 3psi of each other - 109 and 112 cold.
The fuel tank is nearly full, no excess weighty items anywhere in the coach.

I played with the front ride height valve and it operates as expected - raising and lowering the front axle by extending/shorting the rod length between the rubber ends.

The ride height valve has nothing to do with one side not airing up.
The twisting can happen do to the design of the coach (mon·o·coque). The walls are twisting, which can split a windshield..Not air in the tires, or weight in the coach.
I would bet lunch your having an issue with one of the front travel solenoids.They are the top 2 on the front 6 pack.
Chris
Chris and Tammy White  CDA Idaho
Previous owners 1997 U295 36' 3126 Cat 300 HP Build # 4998
Former Foretravel tech & RVIA certified tech
Former owner Custom Satellite home/RV satellites 
Former owner Vans LTD  van conversions
Unemployed, panhandler, drag racer NHRA #6348

Re: Corner leveling problem while driving.

Reply #13 –
Quote from: StevenOrlando –
I can raise/lower the coach in 'level mode'. It will hold pressure for days. The top dash gauge will fall to 0 but the coach remains level. As soon as I enter 'travel mode', the coach will lose pressure on the RF.
My two cents - basically what Mike said in Reply #7...I'm just wording it different:

Top dash air gauge falling to zero indicates a faulty protection valve or check valve on corresponding tank, but that is (likely) a separate problem.

I think the key is to pinpoint where the air can be exhausting when the coach starts dropping on the RF corner.

There are only two places the air pressure can be exhausted:  out the exhaust port on the front height control valve, or out the right side exhaust port on the front 6-pack manifold.

If the air was escaping out the front height control valve exhaust port, then both front corners would fall.  This is not happening.

If the air is coming out the right side 6-pack manifold exhaust port, it means the right side "lower" solenoid valve (the middle valve on the manifold) is not closing completely when it is de-energized.  The solenoid plunger should be removed to check for trash on the seat.

See page 16 of HWH 600 Series Service Manual for system diagram:

https://www.hwhcorp.com/ml11148.pdf
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: Corner leveling problem while driving.

Reply #14 –
Ok, Steven ,something to think about..
You say the level system works. That tells us the raise and dump solenoids are working.
So the trouble begins when you go into the travel mode.
When the green travel lite comes on it tells you that power has been sent to all the travel solenoids, to hold them open so the ride height control valve can control the height of the coach until you come out of the travel mode.
You don't know if they open when the lite comes on and you don't know if they closed when lite goes out.
The air lines that go from the travel solenoids down to the ride height control valve "T" together then go into the ride height control valve so air could now migrate from one side to the other. But if your right travel solenoid didn't open you could end up with more air in the left side when you add air with the front  raise button  (which you said ended up too high) and the ride height control valve would dump air to get the ride height correct. That could be the air noise you hear when you add air.
Sorry this got so long but I think Chris is right. You probably have a bad travel solenoid.
Confirm that you do have 12 volts at the power  in wire at the travel solenoid when the green travel lite is on.
If you do I would change the right travel solenoid or if you don't have a spare valve swap them from side to side to see if the problem moves to the other side.
Like I said, something to think about!
There has to be more to the story.
Like how is the air that started in the right air bags getting out if the right travel solenoid isn't opening?
Maybe be more than one problem.
John Duld
1995 U320C SE 40'

Re: Corner leveling problem while driving.

Reply #15 –
Morning Steven,
Have you been able to solve your problem?
John Duld
1995 U320C SE 40'

Re: Corner leveling problem while driving.

Reply #16 –
You guys probably know this but a quick way to determine if a particular solenoid is energizing is to touch an iron object (nail, screwdriver, etc.) to the coil and see if it sticks.  The coil is an electromagnet so if it is energized anything iron will stick to it.  That doesn't tell you if the valve is open, closed, or leaking but only that the solenoid coil has 12vdc and it is energized.
Forest & Cindy Olivier
1987 log cabin
2011 Roadtrek C210P
no longer 1999 36' U320 build #5522
2013 Rzr 570 & 2018 Ranger XP1000
2006 Lexus GX470
2011 Tahoe LT 4x4
Previous 1998 45' 2 slide Newell, 1993 39' Newell

Re: Corner leveling problem while driving.

Reply #17 –
Morning Steven,
I guess I missed it but can't remember seeing what fixed your level problem.
John Duld
1995 U320C SE 40'