Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Elliott on September 18, 2021, 12:02:21 pm

Title: Airing up the system while on blocks (checking for leaks)
Post by: Elliott on September 18, 2021, 12:02:21 pm
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.
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: Bill and Marsha on September 18, 2021, 12:07:55 pm


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.
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: oldguy on September 18, 2021, 12:14:00 pm
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.
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: craneman on September 18, 2021, 12:28:22 pm
If the coach is leaking completely down you need to replace the protection valves also. 
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: Roger & Susan in Home2 on September 18, 2021, 12:53:55 pm
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 (https://www.foreforums.com/index.php?topic=37333.0)

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. 
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: Elliott on September 18, 2021, 01:07:05 pm
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
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: Pamela & Mike on September 18, 2021, 01:35:27 pm
So you still have #60 lbs. or more  showing on the front/rear air gauges?

Mike
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: gracerace on September 18, 2021, 01:53:01 pm
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
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: Roger & Susan in Home2 on September 18, 2021, 03:34:03 pm
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.
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: Elliott on September 18, 2021, 03:37:21 pm
So you still have #60 lbs. or more  showing on the front/rear air gauges?

Mike
Yup, even many days later
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: Pamela & Mike on September 18, 2021, 04:21:21 pm
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
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: Elliott on September 18, 2021, 04:49:28 pm
I found two more leaks:
[/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.
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: folivier on September 18, 2021, 05:35:31 pm
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.
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: oldguy on September 18, 2021, 05:41:21 pm
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.
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: Michelle on September 18, 2021, 06:10:29 pm
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...
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: Jason on September 18, 2021, 09:19:55 pm
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?
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: craneman on September 18, 2021, 09:25:56 pm
When I raise mine it stays after releasing the button until I lower it even over a week away.
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: oldguy on September 18, 2021, 09:47:59 pm
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.
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: folivier on September 19, 2021, 08:23:21 am
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.
Title: Re: Airing up the system while on blocks (checking for leaks)
Post by: Twig on September 19, 2021, 08:46:22 am
For sealant, use Permatax with teflon. It is white and will outlast you.