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Topic: Airing up the system while on blocks (checking for leaks) (Read 641 times) previous topic - next topic

Airing up the system while on blocks (checking for leaks)

So after rebuilding both six packs, replacing all the airbags, and shutting off air to the step/slide cover, I still have a leak. It's far better than it was for sure but it still completely leaks down over night. I have aired the system up and walked around the coach spraying everything I can with bubble solution and don't see any leaks. There must be a leak somewhere that I can't find without being under the coach.

The problem I have is that to safely get under the coach while it's on blocks, I have to dump the air. How can I block the coach AND apply enough air to the system to be able to hunt down leaks while I'm underneath?

Edit: rethinking this, I suppose I don't need to dump the air now and can just put the HWH panel in manual mode to lower the coach enough to be on blocks but still hold air. This wasn't an option before due to sticking solenoids in the rear six pack. I'll leave this post here incase anyone has other ideas.
1987 Grand Villa ORED
2001 U320 4010

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

Re: Airing up the system while on blocks (checking for leaks)

Reply #1 –
Quote from: Elliott –


The problem I have is that to safely get under the coach while it's on blocks, I have to dump the air.
Why? I raise the coach, put the stands in, build full air pressure then crawl under with wrenches and spray bottle. I'm careful to not put my body in any close spaces if the air bags were to collapse, if they do the stands will hold it up.
Bill and Marsha Kuykendall
1999 Foretravel U320 36' CAI
Build Number 5446
2006 Lexus GX 470

Re: Airing up the system while on blocks (checking for leaks)

Reply #2 –
Do what Bill said. I put the blocks in just leave the coach raised on
the air bags and get to work. One place that was leaking on mine
was the Norgren Valves out the exhaust ports that took forever to find
as I didn't think of that as a place for a leak.
Peter and Frieda Morin
1999 36ft. U320 Foretravel
Build # 5436
1998 Suzuki Sidekick Sport

Re: Airing up the system while on blocks (checking for leaks)

Reply #3 –
If the coach is leaking completely down you need to replace the protection valves also. 
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: Airing up the system while on blocks (checking for leaks)

Reply #4 –
You can air up the wet and service tanks without running the engine to check for leaks.
External Compressor Connection to Add Air to Wet Tank and Service Tanks

I have ramps for either end made from 6x6 treated posts. The extra 5.5" in front makes it much easier to service and check all of the places air can leak in front.  Bottom line is you will likely never find them all.  And if you do, someplace else will start leaking. 
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Airing up the system while on blocks (checking for leaks)

Reply #5 –
Quote from: craneman –
If the coach is leaking completely down you need to replace the protection valves also. 
I should clarify, it's just the stuff downstream from the protection valves that leaks down. Basically it's just not level in the morning
1987 Grand Villa ORED
2001 U320 4010

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

Re: Airing up the system while on blocks (checking for leaks)

Reply #6 –
So you still have #60 lbs. or more  showing on the front/rear air gauges?

Mike
Pamela & Mike 97 U 320

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

Re: Airing up the system while on blocks (checking for leaks)

Reply #7 –
I found a bunch of leaks around the front tanks. Many little ones that add up. If using soapy water, add lots of soap. Some don't show for a while.Sometimes just one big bubble after 1/2hr.

The sealer they used to install all the fittings in the tanks, dries out. Real fun repairing them, because it's like a puzzle, one has to remove this one, then that one, to get to the one that leaks.

I will bet you a free ticket to a Kelly Hughes concert, when you removed your 6 packs (air lines) you have small leaks there. For me,  once I break one of those compression fittings, it doesn't reseal again. That has been my experience. I just went ahead and replaced them when doing any repairs.

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: Airing up the system while on blocks (checking for leaks)

Reply #8 –
Quote from: Elliott –
I should clarify, it's just the stuff downstream from the protection valves that leaks down. Basically it's just not level in the morning

That is only one of several ways out of the air tanks.  The pressure protection valves doe stop leakdown from anywhere else.

If the coach is not level in the AM and it was the night before than it is most likely the HWH tank or the supply to it or any connections from there to the leveling manifolds or from there to the air bags. 

If you leave the leveling system in automatic (two pushes of the air button) and it sags try leaving it in manual mode (one push) when you shut the ignition off.  Add an air gauge to the HWH tank and to the bladder.  My bladder holds air for months, my HWH tank holds enough to keep the bladder inflated for months.  Your compressor should fill the HWH tank to 90+ psi.  You need at least 90 to use that air to adjust level.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Airing up the system while on blocks (checking for leaks)

Reply #9 –
Quote from: Pamela & Mike –
So you still have #60 lbs. or more  showing on the front/rear air gauges?

Mike
Yup, even many days later
1987 Grand Villa ORED
2001 U320 4010

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

Re: Airing up the system while on blocks (checking for leaks)

Reply #10 –
The reason I'm asking is, that this means the check valves at the front/rear are holding and not back feeding.  So you have just divided the system in half so to speak.  No need for me to add to where to look as others have covered that.

Mike
Pamela & Mike 97 U 320

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

Re: Airing up the system while on blocks (checking for leaks)

Reply #11 –
I found two more leaks:
    • Right after the check valve (I believe that's what it is?) on the front tank (pictured). Very subtle and took me a minute to notice.
    • The Norgren valve I mentioned earlier. Shutting down the regulator wasn't quit enough and a small amount of air is sneaking through and leaking out at the valve. The 12v solenoid I ordered should fix this issue
    [/list]

    I forgot to check the front ride height valve when I was under there so I'll have do that too when I go back under.

    Is there anything I need to know when I go in to fix the leak next to the check valve? I'm thinking I'll just replace the check valve while I'm in there for posterities sake.

    Thanks guys.
    1987 Grand Villa ORED
    2001 U320 4010

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

    Re: Airing up the system while on blocks (checking for leaks)

    Reply #12 –
    As Chris mentioned above the sealer can dry out over time.  Also if you try to tighten a fitting that has that type of paste sealant and it is dried you will probably make the leak worse.  I hear often that teflon tape causes problems but if used properly, making sure there is no tape across the opening and is only on the threads there is nothing that works better and lasts longer.  In my career as a technician working with pressure from ounces to over 1000psi I never had a problem using teflon.
    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: Airing up the system while on blocks (checking for leaks)

    Reply #13 –
    I've done a lot of plumbing and I have had teflon tape fail especially with
    pipe 1 inch and over. I now use pipe dope and teflon tape and no failures.
    Peter and Frieda Morin
    1999 36ft. U320 Foretravel
    Build # 5436
    1998 Suzuki Sidekick Sport

    Re: Airing up the system while on blocks (checking for leaks)

    Reply #14 –
    Quote from: folivier –
    I hear often that teflon tape causes problems but if used properly, making sure there is no tape across the opening and is only on the threads there is nothing that works better and lasts longer.  In my career as a technician working with pressure from ounces to over 1000psi I never had a problem using teflon.

    The problem with Teflon tape in the HWH system is that if a small piece breaks off, it can (thanks to Murphy) wind up on the seat of a solenoid valve and cause a leak past that solenoid valve that will be a bugger to find, especially if it happens to be on a raise solenoid...
    Learn every day, but especially from the experiences of others. It's cheaper!  - John C. Bogle

    2000 U320 36' non-slide / WildEBeest Rescue
    2003 U320

    Re: Airing up the system while on blocks (checking for leaks)

    Reply #15 –
    Quote from: Elliott –
    The problem I have is that to safely get under the coach while it's on blocks, I have to dump the air. How can I block the coach AND apply enough air to the system to be able to hunt down leaks while I'm underneath?

    For me, I have the wife push and hold the Raise button all the way up, then I go around putting in the 8 block bars. I then give her the all clear and she releases the button. In a matter of 5-10 seconds, the coach lowers onto all 8. It does not stay fully raised. Does yours not do this?
    Jason
    2000 U295 36' Non-slide  ISC350

    Re: Airing up the system while on blocks (checking for leaks)

    Reply #16 –
    When I raise mine it stays after releasing the button until I lower it even over a week away.
    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: Airing up the system while on blocks (checking for leaks)

    Reply #17 –
    As long as the ignition key is off my coach will stay up and it
    will stay up off the block of at least a week.
    Peter and Frieda Morin
    1999 36ft. U320 Foretravel
    Build # 5436
    1998 Suzuki Sidekick Sport

    Re: Airing up the system while on blocks (checking for leaks)

    Reply #18 –
    The trick to using teflon tape is to wrap tightly in the direction of the threads and make sure none is over the opening.  If done properly there is no way the tape can enter the tubing.  But do what you like, my experience is 27 years working on far more complex systems than HWH.  Using pipe dope there is the possibility of some getting into the tubing and once it dries it can flake off and end up downstream.
    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: Airing up the system while on blocks (checking for leaks)

    Reply #19 –
    For sealant, use Permatax with teflon. It is white and will outlast you.
    1994 U280, Build 4490
    Deming, NM.