While going between campgrounds the passenger side rear tire started rubbing the wheel well. Travel light was on. Used HWH to raise right rear rear side about an inch off wheel well that was as high as it would go. I drove to campsite yesterday. Today same thing no matter how I try to raise right rear it will only raise about 1 inch off the tire.
Any and all help will be appreciated.
I'd check the ride height valve adjusting rod on that position. You can see if you can raise coach manually and make sure the rod hasn't slipped in the rubber collar. Its a good place to start.
jk
First time having trouble with HWH system.
Is there a sensor for height on each wheel?
Checked sensor linkage is tight seams okay
There are two ride height valves in back; one near each set of duals. There is only one in the front, located over the center of front axle. All three need to be set to 8-1/2" front top of top plate down to bottom of bottom plate on each air bag.
see: Ride Height Adjustment (https://www.foreforums.com/index.php?topic=40744.msg404656#msg404656)
jk
Thanks kimosabe99
Tried using raise all button on HWH Key pad front end came up about 9 or 10 in. Both sides Rear only 1 to 1.5 in. Both sides.
When using the HWH control pad to manually raise the coach, you are bypassing the ride height control valves completely and they are not in play. Your symptoms indicate sticking solenoids on the sixpack or a massive leak. If the latter, it'd be loud enough to easily pin point when you're outback standing by the coach. I suppose it could also be something restricting the amount of air entering the rear six pack. Do you get any white powder when you drain the wet tank?
What is the air pressure showing on the dash gauges when trying to use the "RAISE" button to lift the coach?
If air pressure in brake tanks is good (120psi+) and the rear of the coach will not go up using either the (rear) UP arrow or the RAISE button, then proceed with trouble shooting steps from HWH 600 Series manual:
https://hwhcorp.com/ml11148.pdf
Elliott
Cannot hear air leak but engine is running. Is there a way to enter travel with engine off?
Chuck
Both tanks are at 120psi. will read your link.
By the way do you know which gauge hand is for front brakes red or white?
On my coach the red needle is the front brake tank, white is the rear brake tank.
To enter Travel mode with engine off, simply turn ignition key to ON position. Your dash gauges should come on, and the green Travel light should illuminate (assuming air system is at about 80psi or better).
To directly answer your question: probably - every HWH panel seems to behave a little differently. On mine, I can enter travel mode by just having the ignition on and pressing the "off" button on the HWH panel and I suspect it'll be the same for you.
However, a better test would be to air both your tanks up completely, shut the engine off, and then put the hwh panel in "manual" mode and attempt to raise the rear of the coach. If the coach doesn't raise at that point, and you don't hear a huge leak, you don't have air getting to your airbags from the six pack (so either one ore more solenoids are sticking or air isn't getting to the six pack despite no leaks, which I've never hear of but is possible)
Oh - one other thought: make sure you have a little air in the front airbags when you perform this test. If your coach is the same as mine (Chuck can probably tell us), you have two pressure switches on the front six pack and if they don't read ~15psi they'll prevent you from raising the rear end up. This is to save the coach from twisting so much that you crack the class.
Actually, the front pressure switches can only inhibit the
lowering function in the front of the coach. They have no control over the raising function. See excerpt below from
HWH Air Leveling Systems Text Book:
https://www.hwhcorp.com/ml20635.pdf
"The front air pressure switches on all 600 and 680 Series Leveling Systems are used during any lower functions, manual operation, automatic operation or use of the "DUMP" button. When the pressure switch for a front bag turns on, it sends a ground signal to the control box. This will inhibit the opposite side front air bags from lowering.
EXAMPLE: While pushing the right side lower button, the right front air pressure switch sees low air pressure. The front lower button is then pushed. The right front lower solenoid valve will turn on and open, but the left front lower solenoid valve will not turn on. The left front bag will not lower. This is done to prevent the front of the vehicle from twisting. If one side of the front of the vehicle is as low as it can go, lowering the other side will twist the vehicle."
With engine off and Key on it stays on travel mode and I can hear air coming from travel Valve on passenger rear. Not a tremendous amount but some. With both tanks full 120psi.key off pressing rear up button runs aux compressor raises RR about .5 on. LR about 1.5 in.. after setting a few minutes RR settles back down on tire.
Ah thanks Chunk, I had it backwards ^.^d
This to me sounds like sticking solenoids on the rear six pack. Probably time to rebuild your rear six pack
This long distance trouble shooting is difficult. So much easier when there in person to see and hear what's going on.
Are you sure the air you hear escaping is coming from the height control valve (leveling valve)? The rear 6-pack is in the same general vicinity. You might be hearing air escaping from the exhaust ports on the 6-pack. Can you hold you hand under the height control valve and feel air coming out? The exhaust port is on the bottom of the valve.
If you have 120psi in the brake tanks and try to raise the rear with the UP arrow, it should use the pressure in the tank. It should not run the aux compressor until tank pressure is depleted. This is puzzling. Trying to think what would cause that to happen. Perhaps the HWH control box is not seeing the signal from the system pressure switch on the rear 6-pack and thinks the air system pressure is depleted. The aux compressor on these old coaches is very weak. Even if it was working perfectly, it would take the aux compressor forever to raise the rear of the coach off the tires up to travel height.
I am a full timer leaving Florida heading to Virginia where will be visiting relatives. I have no kit so it will be kind of hard to rebuild. Is there a common failure and a possible work around. Also where do you get the rebuild kits.
Chuck
There is a little air coming from bottom of ride height Valve. Not as much as I am hearing. Could be coming from six pack. Will not raise high enough for me to squeeze under to check.
You get the kits from Tom McCloud. You send him a email and tell him how many kits you want, and he tells you what they cost and if he has them in stock. You should order two kits if you are interested. See link below:
Replica HWH Plungers Redux (https://www.foreforums.com/index.php?topic=28733.msg469377#msg469377)
Yes, it's going to be very difficult to do any trouble shooting unless you can get the coach back to at least ride height in the back.
There is a work-around to take the ride height valves out of service by pulling a fuse (#11) in the HWH control box, but that doesn't work unless you can get the coach up to ride height.
You could look at the HWH control box to see if any of the fuses are blown. That is one of the steps in the trouble shooting section of the manual that I linked earlier. Pay particular attention the the fuses (#7 and #8) for the left and right rear RAISE solenoids. The control box should be on the front wall or possibly on the ceiling in the front storage bay. It is an aluminum box with a removable lid. Mine is next to generator cooling duct. Fuses are inside the box. Fuse diagram on page below.
Gary & Kathy,
I don't know where you guys are located in Florida. We have a trusted mechanic friend of the Forum who has a construction company in Leesburg, FL. His name is Paul Yasbeck. You might try giving him a call to see if he has any ideas about your problem. I have no idea if he is home, or traveling, or what, but if he answers I think he would at least offer you his thoughts on this problem.
Foretravel Inspector in FL (https://www.foreforums.com/index.php?topic=46138)
https://www.yasbeckconstruction.com
Paul is listed on the Foretravel Service Center Referral List:
http://www.foretravel.com/img/pages/photo/1577780524_owner_service_recommended_service_referral_list_file_path.pdf
Calling it quits for today, going to go over all the information you'll have given me and try to get it digested enough to make some sense of it. Will be doing something in the morning even if it is wrong.
Perfect timing, Tom McCloud just posted that he has more rebuild kits!
You can bypass the ride height valves by putting 12V's to the grey wires (as I recall, there is a thread here about this) in the control unit. You will be able to drive it to where ever you want.
To bypass the ride height valves you pull a fuse that is labeled Travel in the control. In my 1997 U295 you had to crawl in the front compartment, remove a cover over the area, and then remove cover on HWH box. For some reason "7" comes to mind. Not sure if that was amps of fuse or the fuse was in the 7th location. You can still adjust the air bags manually. Once you set it stays there unless you have a air leak between the bags and 6 pack.
If you remove the travel fuse and manually raise the coach, then it should stay at that height. If it doesn't then you have an air leak somewhere. You might have to get a couple of small jacks to place on the frame by the air bags to get it raised so that you can get under it.
If you read this thread from the first post, you'll see that Gary's problem is the coach won't raise up in the rear no matter what he tries. He has tried letting it come up in travel mode, and tried raising it manually, and nothing works. If he could get it up to travel height, then the "pulling fuse #11" trick would work. But he can't...
Found the thread linked below that may offer some clues...
Travel Mode / Ride Height Problem (https://www.foreforums.com/index.php?topic=39814)
Was reading over posts of today and Chuck said
If you have 120psi in the brake tanks and try to raise the rear with the UP arrow, it should use the pressure in the tank. It should not run the aux compressor until tank pressure is depleted. This is puzzling. Trying to think what would cause that to happen. Perhaps the HWH control box is not seeing the signal from the system pressure switch on the rear 6-pack and thinks the air system pressure is depleted. The aux compressor on these old coaches is very weak. Even if it was working perfectly, it would take the aux compressor forever to raise the rear of the coach off the tires up to travel height.
So I tested this by bringing pressure to 120psi.
And with key on engine running HWH off used all up button and it started aux compressor to try to raise RV. Only front will come up about 9in. Rear about 1.5in. put HWH in one push of air button and any button I push to raise any section runs aux compressor. If I push all rise button it starts aux compressor. All this with engine running and pressure at 120psi. If I set to auto level and it needs to raise a section it runs the aux compressor. Is this wrong?
The only time it does not use aux compressor is when it is trying to reach level (HWH off and engine running) then it raises the front properly and the rear only a 1.5in.off wheel.
Gary,
Following is a excerpt from HWH Systems Text Book. It describes the action of the "single output" aux compressor, which is what you and I have on our coaches. On our coaches, the aux compressor is plumbed directly to the 6-pack manifolds, and is only used to support the leveling system. It does not add pressure to the rest of the air system. It should not run when the air system pressure is at 120 psi.
"Anytime a raise function - automatic, manual up arrow or the "RAISE" button - is being used, a +12 volt signal is sent to the compressor from the control box. This turns a single output compressor on if air pressure in the system is below approximately 105 psi."
Question: When you try the tests described above and the front end comes up 9", do you observe the air pressure in the front brake tank going down? That would be the red needle on your air pressure gauge.
As Chuck said when rising the coach the air pressure should go down. My coach the pressure goes down
a lot and then is takes awhile until the pressure gets built up and the coach up to put the blocks in.
Chuck My 2001 commands the compressor on regardless of system pressure. It's hooked up to shop air threw the dryer and set just below blow off pressure. I put in raise last week to run off a stray cat and noticed it running till I shut the raise off. Maybe I have something wrong?
Scott
Will test this in the morning.
Thank you Chuck, Elliott, Twig and everyone. This forum is truly a store of knowledge 😃
No, nothing wrong. Your 2001 air system is totally different (air routing) from our old early 90's models. Yours is much more complex.
See the page linked below for a description of the two different aux compressor setups. The "simple" setup is like the old coaches. The second more complex air compressor (like your newer coach) has two outlets, one is for the leveling system and the other supplies air to the main vehicle air system.
That thread I linked up above (Reply #28) had a post by John Morales that caught my eye. He said (Reply #16):
"The back would not come up to clear the Travel Mode. I had a stuck Protection Valve. It should be on the tank in front between the tank and the air line. Sometimes you can break them loose by tapping on it."
We will know tomorrow morning if this is the key to Gary's problem. If his front pressure gauge is going down when the front end comes up, that means the front raise solenoids are opening.
If the back raise solenoids are also opening, but the rear bags are not filling, then the air supply from the rear brake tank must be blocked. Where would that most likely happen: the rear tank protection valve!
This would also explain why the coach won't go to TRAVEL mode. If all 4 travel solenoids are opening (front and rear) than the front would come up as normal. The rear, however, would not rise - because no air pressure is reaching the 6-pack.
This would also explain why the aux compressor is running in both raise and travel modes, even with 120 psi in the air tanks. Since it is tied in downstream of the protection valve, it would see (when the rear solenoids open) the big drop in air pressure in the line from the rear brake tank to the rear 6-pack and that would activate the compressor. Its meager output would actually try to inflate the rear air bags. But as I said, those little compressors are usually so pathetic that it can only raise the rear end a inch or so (in the short time Gary was watching it).
SO, that is my hope - that we hear from Gary tomorrow that the front tank pressure is going down as the front end goes up. Fingers crossed!
Protection Valve (Reply #90) Part Number Collection (https://www.foreforums.com/index.php?topic=11472.msg225770#msg225770)
Didn't want to disturb neighbors too early.
Chuck
When doing test this morning.
Started with RV all way down.
With air pressure at 120psi. HWH on, not in auto level. Pressed off button to imitate travel. Travel light comes on and both gauge needles start falling as RV rises to travel height. They both fall to 90 psi then go back to 120psi. Takes less than 5 minutes.
Rear only rises about 1.5 in. Front about 9in.
Compressor never comes on while rising to travel.
Seams like everything is working except rear never getting to proper height.
I am thinking leak in 6pack?
Can you try the same sequence - start with coach down at both ends. Engine running, with 120 psi in both tanks, press AIR button once to turn on the leveling system. The TRAVEL light should not be illuminated. Then use the RAISE button to try to raise coach. Continue to hold the RAISE button down while you watch the air pressure drop in both tanks and then come back up to 120 in both tanks. See how that works.
Chuck
Did test as you asked, to the point I was getting concerned about my new windshields with the right rear not rising bit about 2 in. Front went up 10 or 11 in. Left rear 4in. Right rear pushing 2in.
Both gauges continued to fall as long as I held button. Compressor ran whole time.
Did same thing using raise rear button right rear would not go more than 2in. Left rear about 5in.
Right rear goes back to bottom when button released.
Wish I could get under to listen for leaks
Yes, definitely do not want to twist the chassis and pop a windshield!
OK, unfortunately, the fact that
both air tanks are dropping pressure rules out the theory I presented last night - "the stuck protection valve theory". If it was the protection valve on the rear tank sticking then you would
not see a drop in that tank pressure. The air from
both tanks is going to the 6-pack manifolds. At the rear end it is getting "lost" somewhere so very little pressure remains to inflate the bags. It is sounding more and more like a big air leak somewhere at the rear end. Perhaps a split in one of the right rear air bags or a hole in a air line? I am running out of ideas...sorry.
Did you consider trying to contact Paul Yasbeck?
Another person to call if in Florida is Red Tractor on this forum. He is just south of Tampa on I-75. Send him a PM if he can assist you. Very good at Foretravel repair.
Great idea! Use the PM button on his profile page:
https://www.foreforums.com/index.php?action=profile;u=1552
Was hoping it would be something I could do.
Just had new windshields and tires. Running low on coach bucks.
Will see if I can safely get underneath to find leak.
Thanks so much for your help and everyone else 🙏
I am near lake city Florida in Ocean pond campground. About 30 miles from Georgia line
Don't want to actually get your body parts under coach anywhere they could get crushed!
You could try this: Run engine, get air pressure up to 120psi, use dump button (or down arrows) to lower coach down at all 4 corners, shut off engine. Open the rearmost passenger side storage bay compartment (the one behind the right rear wheels). While you (Gary) listen next to the right rear wheel well and the open compartment hatch, have Kathy push the AIR button once (to turn on the system) and then try pushing the
rear UP arrow for a few seconds at a time. This will send air pressure through the 6-pack "raise" solenoids to the air bags on both rear corners. Gary - try to listen for any noise indicating escaping air. I'm hoping by isolating the UP (raise) command to the rear of the coach, and with engine off, that you might hear where the air is escaping. You may not be able to actually reach or see where it is leaking, but could at least verify it is a leak.
And as noted, don't hold the UP button down long enough that chassis gets twisted. Probably won't have enough pressure in the tank to do that anyway.
Do you have the air system diagram for your coach? This would be essential to anyone trying to work on this problem. If you don't have one, Forum library link below is the one for my coach. Yours should be the same.
https://www.foreforums.com/index.php?action=media;sa=item;in=4969#viewitem
How about trying this. Run engine where both air tanks are at 120. Shut engine off. Turn key on. Once travel light comes on go and check rear to see if you hear air leaking. This should tell you if you have a leak in a feed line to the ride height, and or the feed to the 6 pack.
The only way I can see you get under the coach is to drive up on 2x12's to get high enough to be able to get under coach.
Wife had an ingenious way to get under RV.
Wait for it!!
Drive on some leveling blocks (2x6 )
Same as turbojack
🤔
Gary,
If you are getting any air out of the ride height control valve vent when that corner is low either the arm (linkage) has slipped or the valve is bad and should be replaced.
The valve always moves the coach in the direction the arm is pointing.
If that corner is low the arm should be pointing up.
When at travel height it should be parallel to the ground. Off.
I'm not sure how much it would affect raising the coach if that valve is venting pressure off but a leak needs to be fixed.
Also if you think you hear a leak at the manifold I would swap the dump solenoids for a start.
If you have air exhausting from the ride-height control valves while you are not in travel mode, then you definitely have a leaking travel solenoid. The ride height control valves should be inert at all times unless you are in travel mode.
The amount of air coming from ride height value is minimal. Rod is pointing up and is tight.
If air is coming out of ride height control and coach is low then as Elliot has said either the adjustment is off, or bad height valve.
Just back from under RV looking for leaks.
None found with exception of small amount coming from bottom of ride height control.
Took air line off one airbag. And disconnected linkage to controller. Put HWH in travel mode.
With controller linkage pointing down there is no air going to airbag. With controller linkage point up lots of air goes to airbag but don't know how much pressure. Connected air line back to airbag with linkage up airbag raises RV about an inch off wheel.
Hypotheses: there must be a internal leak somewhere. But if there is where is it going.
Your brake tanks are under the nose of your coach. If the same as ours the tank on the driver side is the rear brake tank. This is the origin of air line (#27) that supplies the pressure to rear 6-pack. You might take a look at that air line where it connects to tank. See if you can detect any leaks. See photos in link below for valve arrangements at brake tanks.
Air Tank Valves R&R (https://www.foreforums.com/index.php?topic=27638.msg226700#msg226700)
Going to auto store to get pressure gauge so I can see how much pressure is to airbags
Gary, By chance did you recently place anything under your Couch? The level sensor is located there near the drawer under the couch, attached to the floor. It could have gotten bumped... ::) If you jack-knife the sleeper couch look on the floor on the left side next to the closed drawer..
Connected gauge to line going to airbag couldn't get a tee so just attaching to line of one air bag on right rear. Built pressure on tanks then put in travel mode. Pressure built up to over 105psi.
Would think that would lift the RV.
Does anyone know what pressure it takes to lift your RV?
Then connected to one of the front airbag lines and it reached ride height at 40psi.?
Then 105psi should at least lift to travel level.
Puzzling to say the least.
Most systems are designed to operate well below max output I would guess pressure between 60 and 90 psi. Should raise the RV to travel height.
Scratching high and low
:headwall:
Here is from my ih45. Not sure when picture was taken. Maybe in a turn. This is heavy coach. Only 2 air bags for front, drive has 4 so less air needed
With this information, thinking air bag has a leak?
or something physically restricting it from coming up (siezed shock?)
That was my thought after post #52 where plenty of air being sent to air bags on the side in question, but the other side not coming up much more is curious (unless leak is so gross that there's not enough air left for other side).
Got one more test to do.
Instead of trying to raise the rear, try raising the side. This will take the other rear air bags out of the loop.
It is very possible that one of the 2 bags is leaking. You could hook up each bag to an external air source and see if leak shows up
When raising the sides only left side front rises 8or 9 in Left rear raises about 6in.
Rising right side front rises 8 or 9in. Rear rises 1.5in.
Going to find tee so I can see what's going on with RR it either has a Leah or something preventing it from going up.
After getting fitting to tee into line when trying to get to travel height only getting 70 psi.
Therefore the air bag I am teeing into must be leaking. Knowing that I still cannot feel the air from the leak.
Any one know what airbag i need?
And how to get RV raised enough to change it.
Make sure it is the air bag and not something else. Disconnect the air line going to the air bag and
check the pressure. If it pressures up than that bag is probably the problem if it doesn't do the other
bag. If it pressures up that bag is the problem if not the leak is somewhere else. Jack up the frame
and then put your blocks in.
Thanks but that is what I did in post 56
From the testing you did, I am now 98% feel your problem is a leaking air bag or bags. If after airing up with gauge in line you got the same 105 PSI reading and the side did not go up, only then would I think you have a problem keeping the side raising
There are a number of threads on here about where to buy and what air bags to buy. If you do a search you should find them and if you can't, I bet Michelle, the search expert, will.
That is a common air bag. Part Number W01-358-9448 should be available at most part stores..
Do you know which air bag is leaking.
Thanks Gerry
Oldguy rear most passenger side
Found a mobile RV mechanic. He is trying to find a airbag. So cleaned some love bugs off RV and enjoying campground :sleepy:
Here's the NAPA info for you
https://www.napaonline.com/en/p/NHD4529448L?impressionRank=2
Find It Parts has them for 146.00
Very interesting thread. Salute to those that contributed to it. Chuck you did great job of trying to remotely diagnose a difficult
issue we all have faced.
Gary one thing more to check is the output of your 12v compressor and for leaks there. I had several big leaks around the compressor T that had the high pressure release valve. Also at the bottom of the plastic bowl there's a O ring that was bad on mine. Still trying to hunt down all my leaks. Very frustrating. I would replace all the air bags on the coach if that is found to be the problem. if one is bad....
Good luck and hope you figure it out.
Also get the 6 pack rebuild kits from Tom.
bob
Update:
Airbag was supposedly ordered Friday and should have been here today. They were not in shipment so they called and found out it had not been processed for delivery which means bag won't be here until Wednesday. :facepalm:
This is a nice campground except for the deer fly's they will eat you alive bug spray or not.
Enjoy 😍
New airbag installed and working. Have driven about 500 mi and everything is as it should be.
The gauge I installed at the airbag reads 68 psi when in travel position.
Thanks 🙏 to everyone for all the help and knowledge.
Side note shouldn't there be a stop to keep tire from rubbing wheel well?)
Perhaps there should be a stop...but there isn't one. Just one of those Foretravel oddities.
Nearly every older coach you look at will have some rub marks in the top of the rear wheel wells.
Since air bag did have a bad leak, you were not able to hear it?
My wheel wells were worn threw and I was going to make stops but after I repaired them I use
a graphite mix with the epoxy from West Systems and there is no sign of wear so I haven't bothered.
I find that fact to be interesting. Don't worry - I'm not saying there is anything wrong with what you say - just interesting. I have always assumed that it required higher pressure than that to raise the rear of the coach...since it is so heavy. But, apparently not!
The HWH Leveling System Textbook says:
"Although it may vary between different vehicles, it normally takes at least 60 psi to start lifting a vehicle. Most vehicles will require 90 psi to obtain maximum lift. Some may require up to 130 psi to obtain maximum lift."
Of course, that's talking about "maximum lift", not travel height. Also, perhaps that comment pertains more to later model heavier coaches. Our old GVs are relatively light compared to Unicoaches.
Not having stop before tire rubbing Seems odd.
Will check pressure again tomorrow. Old eyes may have deceived me. 😲
As long as you turn off the engine with air pressure over 100 PSI, and suspension is in TRAVEL MODE, you should be able to hear any massive leak.
How quickly does pressure drop under the above conditions?
With old airbag with leak it would only rise about 1in. From wheel well to tire. As soon as engine turned off would settle down on tire. No time to listen for leaks.
Rechecked gauge this morning. Gauge indicated 70 psi with RV raised to travel height.
Think this adventure is over.
Thanks everyone!