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Topic: Overnight Air Leakdown (Read 3227 times) previous topic - next topic

Re: Overnight Air Leakdown

Reply #25 –
according to drawing # B-2031 there are two "protection valves" in the pneumatic system. One on each tank.
The Protection Valve is to protect lose of air due to a leak in the HWH system. It will shut off pressure to the HWH @ 60 psi.
SO--- If leak is in HWH system, air pressure drop should stop @ 60 psi.
    I do not think my system has a "protection" valve, but a pressure reducing valave, as it has a safety wired knob on the valve. My system will leak to about 50 psi in 24 hours. And continue on to "0" in next 8 hours.
I have been fighting this leak for several months.
By disconnecting and capping off lines, I have eliminated the HWH system. Use of homemade "leak solution" of soap & water have found no Leaks @ the tanks or attached fitting. I found two small leaks (did not make much difference in leak down rate) @ the intersection of the lines behind the instrument panel. ( Airhorn valve it's self and attached hose )
I have not gotten to the rear end as yet, due to limited physical ability at this time.
Also cannot locate the Spring Brake control valve.
Since I will not be traveling for the next couple of months, this is not a "NOW" item. But I Will continue until it is back to hold max pressure for days @ a time

Bill Chaplin



1993 U300, 6v92
build 4366
USAF retired, Flight Engineer, C124, C130
 ATP, A & E.  & ex AI

Re: Overnight Air Leakdown

Reply #26 –
Yeah I know it sounds silly but for air leak detection I use children's bubble blowing solution.  Its cheap so when I knock the bottle over I don't cry about it and its available everywhere.
Gary B

Re: Overnight Air Leakdown

Reply #27 –
Quote from: Pamela & Mike –
After accidentally finding and fixing the internal air dryer air leak ours will remain above #100 for several days. Once it drops to about #90 after a week it will set there for several weeks like Dave M's does.

After foolishly thinking I could go longer before servicing the air dryer, I had it replaced.
I had a lot of white stuff that had to be cleaned before replacing the Air Dryer.

My Aux Compressor gets quite a workout and trips the 40 amp circuit breaker. I was going to replace the HWH resettable C/B (and still might) even though I could never get an amp reading over 28 amps on that line with Aux Compressor running and never was able to actually be there when it tripped. I hate intermittent problems. >:( 
The selected media item is not currently available.Barry BEAM #16014
2003 U320 40' AGDS
Beamalarm, Foretravel technical help and specifications
"Whatever the mind can conceive and believe, it can achieve"

Re: Overnight Air Leakdown

Reply #28 –
Back to this topic and my comment on my thoughts that the step cylinders are maybe causing some of my leak problems. To which Ruth said they make underpants to control leaks!!!
Today I decided I was going to test the cylinders and yes, they do leak badly in the "up" position. So, off they came. Not too easy to get those little bolts out but did it. To replace the bolts thru the brackets and fibreglass box I tack welded the bolts to each side of brkt and just had to push them thru box and put the washers and nuts on the back. A quick zip with an airgun and socket at the rear and they where back. I had 2 that were graciously given to me from Jeff and Carol while I was at Xtreme and they were having the step conversion done at the same time, so thanks Guys they work great!
I am expecting to see a big improvement is retained air in the morning.
John H
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.

Re: Overnight Air Leakdown

Reply #29 –
John
 Are those cylinders rebuildable?

Barry & Donna
2003 U320 PBBS 4020
Build #6165
Dodge RAM Crew Cab 3500 4x4
2001 Jeep Cherokee Limited
Skip # 102803 Motorcade # 17271
FMCA # 408218

Re: Overnight Air Leakdown

Reply #30 –
Check the air/water drain valves at the front and rear of your coach. I just spent many hours trying to find my leakdown points and 2 of the 3 valves at the front were leaking at the line to valve connection. I replaced all of them.
Dean & Deirdre

2012 Arctic Fox 22GQ
Was 2003 U270

Re: Overnight Air Leakdown

Reply #31 –
We had a overnight leakdown on our coach.  the main culprits were the accelerator pedal and the dash gauge. 

Oldmattb
Matt B
1998 u-320

Re: Overnight Air Leakdown

Reply #32 –
well I have not been out to check yet if the air is still up but I can see that the step is still in the up position so that is a big difference from before the change.
I will have a go at taking the cyl's apart -just for fun- and see a kind of lock-pin into the end to secure it from unthreading off, but doubt that that would happen. Maybe they are Locktited on. We will see.
D & D- I do not have the vales-3-as you do just 1 by  the wheel. I have to get to tanks to drain. I will be checking them out too, but if I am not mistaken I may have stopped the main leak already.
John
Coachless, now use aircraft. 2003 Ford Travelair TC280 class C. Super shape. Just for 1 yr .
1994 Ford E350 ClassC,total renovation inside and out. Now sold.
2000 U295  36' Cummins 350 c/w Banks Stinger, Resonator upgrade,Solar, LED lites.Residential fridge with slide out pantry. Build 5674. Sold
ex 92 GV 022C ored Cummins. Sold
ex 95 GV240 cat 3116. Sold
2017 Mini cooper s & 2016 land Rover LR2 HSE  LUX.
jhaygarth@aol.com    SKP #130098
treat everyone as you would like to be.