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Topic: HELP! (Read 499 times) previous topic - next topic

HELP!

Non-emergency, but I do want to fix it.

I just finished rebuilding the six packs, and now the front leaks down quickly.  It appears the passenger side is leaking down faster than the driver, but it may be uneven pavement.  Leak is quick, from full up, to tire on the wheel well in maybe 15-20 minutes.

I checked the hose connections and the bases of the solenoids after I reinstalled the front six pack, and saw no evidence of leaks.

Is there a particular place for me to look?
Matt B
1998 u-320

Re: HELP!

Reply #1 –
check your front right height control valve to see if that's leaking out. It's possible that one of the solenoids is sticking and it's leaking out somewhere else downstream. If it's leaking out as quick as you suggest, You could probably hear it if it's quiet and you crawl underneath there.

Also make sure you didn't strip out the solenoid valve in the block. It's pretty easy to do with brass on aluminum. that had happened on my coach before I acquired it and it was super hard to identify the leak. I ultimately did it by process of elimination

1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: HELP!

Reply #2 –
No sound from BESIDE the coach.  The dash pressure gauges are not depleting.  I am getting ready to block the suspension up again.
Matt B
1998 u-320

Re: HELP!

Reply #3 –
For what it's worth, no air should be able to pass beyond the six pack with the HWH system in manual mode. If it does, you know you have a leak at the six pack or a stuck valve since they should all be closed.
1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: HELP!

Reply #4 –
Being that you just did the 6 pack I would say that it is in the 6 pack solenoid valves. Did you take the lines off the 6 pack? If you did it could be a fitting. Get a squirt bottle of soap mixture and check for leaks. Happy hunting. Ron
previous 1984 35 ft ORED 250 HP 3208 Cat       
previous 1998 40 ft U295 CAI 325 hp Cummins
previous 2003 40 Ft u320 build #6140 450 Cummins M11.                                                         
1999 Mazda Miata
Ron, Nancy, Tipper the cat, Max The dog
1997 U 270 36 ft build number 5174 8.3 Cummins

Re: HELP!

Reply #5 –
I blocked the chassis and added some air so the body would not be resting on the blocks.  I got under and bathed the lines and solenoid bases with the leak detect bubbly stuff.  No signs of leaks, no sounds.  I don't know if it is a workable strategy, but I listened to the solenoids with a stethoscope and did not hear anything.

It may be leaking down more slowly...  I didn't see any visible drop in the ten minutes I was underneath.

It is not clear to me what the particular solenoids do.  Can we identify a particular one, based on the symptom?
Matt B
1998 u-320

Re: HELP!

Reply #6 –
I aired up again, unbolted the six pack from the RV frame and listened close.  I may have heard a hiss.  I THINK I felt air on my face.  Airing up again to douse the area with bubble goop.
Matt B
1998 u-320

Re: HELP!

Reply #7 –
Quote from: oldmattb –
It is not clear to me what the particular solenoids do.  Can we identify a particular one, based on the symptom?
Here's a diagram of which solenoid is which: HWH 680 Manifold Internal Airflow Diagram

If the either of the "lower" solenoids are sticking open, the front would leak down like you suggest. Similarly, if you have a leaky front ride height control valve, sticking travel solenoids would also cause the front to leak down. It's also possible that a raise solenoid is sticking and it's going out the feed line and leaking up stream.

As much as I hate to say it though, I had the exact same symptoms when I had a stripped out block where one of the solenoid valves entered. I never did see the leak despite numerous attempts with bubble solution. I only ever identified the issuer after double checking all the solenoids were tight and I had one spin free. Even then, I wasn't ever able to spot a bubble when I suspected that to be the issue. I finally got a new manifold at that solved the problem.

If I were you, I'd pull the manifold with solenoids intact and check that each solenoid is working by hooking it up to a 12v source and hearing it click. Assuming all of them engage/disengage, I'd then suspect a leak at the manifold like I had.

1987 Grand Villa ORED
2001 U320 4010

Not all that wander are lost... but I often am.

Re: HELP!

Reply #8 –
I aired up again, unbolted the six pack from the RV frame and listened close.  I may have heard a hiss.  I THINK I felt air on my face.  Airedup again to douse the area with bubble goop.

With the six pack in place it was the top right solenoid.  It was leaking between the solenoid and the base that screws in to the manifold.

Use my special wrench to tighten, and waiting to check the results.
Matt B
1998 u-320

Re: HELP!

Reply #9 –
Elliott,

I too stripped one of the solenoid openings on the block, but I saw it before the six pack was reinstalled.  Years ago, I would have jammed that thing in and kept twisting until it sat flat or fell apart.  More mature me, sat and restored the threads with a dental pick.  I was rather proud of myself being so patient, and reflecting on what failure might cost me.  Steel threads and a brass base should have suggested to me to be more careful!

In any case, that was not the one leaking.  Given that I had an external leak, I am supposing that the internals are OK.  I will go out and check on the status in a bit.  I have a tape measure sitting against the wheel well.
Matt B
1998 u-320

Re: HELP!

Reply #11 –
Leak appears to be gone. Thanks guys!
Matt B
1998 u-320

Re: HELP!

Reply #12 –
Matt answering you question in item 5 what do all of the solenoids do?
The top two solenoids are the travel solenoids.
Powered open only when the green travel lite is on so the ride height control valves can let air in or out of the air bags as necessary as you drive along.

The middle two solenoids are the dump solenoids. They vent air out of the air bags through a small hole in the manifold next to the dump valves when in the level mode and any dump signal either a manual or computer signal is sent to the dump solenoid.

The bottom two solenoids are the raise solenoids. They open only when in the level mode when any raise signal is sent to them either a manual or computer signal allowing coach air to go to the airbags.
John Duld
1995 U320C SE 40'
 

Re: HELP!

Reply #13 –
Quote from: John Duld –
Matt answering you question in item 5 what do all of the solenoids do?
The top two solenoids are the travel solenoids.
Powered open only when the green travel lite is on so the ride height control valves can let air in or out of the air bags as necessary as you drive along.

The middle two solenoids are the dump solenoids. They vent air out of the air bags through a small hole in the manifold next to the dump valves when in the level mode and any dump signal either a manual or computer signal is sent to the dump solenoid.

The bottom two solenoids are the raise solenoids. They open only when in the level mode when any raise signal is sent to them either a manual or computer signal allowing coach air to go to the airbags.

Thanks for that.  Between your information and the diagram above, I understand better what the problem was.
Matt B
1998 u-320