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Topic: Pressure Protection Valves at front air tanks (Read 1515 times) previous topic - next topic

Pressure Protection Valves at front air tanks

SAFETY ALERT

If you have an older coach, like we do, the condition of the diaphragm is probably questionable. I found both of ours are cracked and in need of repair. The OEM part N15759DG is no longer available. The replacement P/N is 90555399. 
From what I can tell you will never know this part is bad until the day you really need it  :o

https://www.haldex.com/globalassets/north-america/documents/suspension-controls/l55297w

Bob
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: Pressure Protection Valves at front air tanks

Reply #1 –
I used these. Cheap as chips, work fine:

PRESSURE PROTECTION VALVE - 1/4" NPT - REPLACES KN31000 9054107 842234136687...

Mine were both leaking bad too. Look close, I found a bunch of other leaks in the fittings in the tanks. Good time to fix. All small, but add up. The sealer gets old.
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: Pressure Protection Valves at front air tanks

Reply #3 –
Bob, how did you find out they have gone bad??
JohnH
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: Pressure Protection Valves at front air tanks

Reply #4 –
Mine started leaking.. order the ones above .. replaced yesterday .. both bad .. parts were cheap enough to replace and not fiddle with cleaning

Re: Pressure Protection Valves at front air tanks

Reply #5 –
John,
I had to take one apart to remove it.
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: Pressure Protection Valves at front air tanks

Reply #6 –
Quote from: Bob Rozek –
John,
I had to take one apart to remove it.
Why did you have to take it apart to remove it?
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Pressure Protection Valves at front air tanks

Reply #7 –
Bob my question was about what happened to it that made you feel it's faulty?
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.

Re: Pressure Protection Valves at front air tanks

Reply #8 –
jcus,
It was in the way of removing the front brakes check valve. FT did not leave enough
room to rotate that assembly without disassembling most of the parts. 
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: Pressure Protection Valves at front air tanks

Reply #9 –
Quote from: Bob Rozek –
jcus,
It was in the way of removing the front brakes check valve. FT did not leave enough
room to rotate that assembly without disassembling most of the parts. 
Agree with that, had to disassemble mine piece by piece. As has been said, if going to all this trouble, might as well replace check valves as well as protection valves.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Pressure Protection Valves at front air tanks

Reply #10 –
John,
Both of the valves were still functioning. The diaphragms are very thin and had substantial cracks all the way around.
I don't want to take a chance on a $15 part that is over 21 years old.

Bob







The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: Pressure Protection Valves at front air tanks

Reply #11 –
jcus,
The check valves I have are a two way check. It has a spool with a rubber cap on each end. The spool shuttles either direction depending on the air supply source. One spool was stuck.

Bob
The selected media item is not currently available.Bob & Faith Rozek
1997 U320 40'
Xtreme Remodel
2010 Scion XD

Re: Pressure Protection Valves at front air tanks

Reply #12 –
Bob, some coaches have a single check valve before protection valve.
It is the round aluminum fitting. Maybe only on newer coaches.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Pressure Protection Valves at front air tanks

Reply #13 –
Is there some DOT type reason not to insert a union at the base of the assembly to facilitate R&R? That sure would make things easier for future maintenance!
Don
The selected media item is not currently available.
Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Pressure Protection Valves at front air tanks

Reply #14 –
Quote from: Don & Tys (AKA acousticart) –
Is there some DOT type reason not to insert a union at the base of the assembly to facilitate R&R? That sure would make things easier for future maintenance!
Don
It certainly would, but I think all fittings used in air brake system must be DOT approved. https://www.lawsonproducts.com/pdfs/PIRFP_AB_Hose_Tubing_Fittings_PI.pdf
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.

Re: Pressure Protection Valves at front air tanks

Reply #15 –
Great to have all the part numbers and sources listed in this thread.
How many of each are required?
Is it only for the front?
THANKS!
1995 U320C SE 40'
Jeep 4x4 Commander - Limited - Hemi
"The Pack"  Yogi and Diesel our Airedales -  Charlie our Boxer/Akita mix. Gone but NEVER forgotten Jake our yellow Lab.
NRA Law Enforcement Firearms instructor - Handgun/shotgun
Regional Firearms instructor for national Armored Transp. Co.
 

Re: Pressure Protection Valves at front air tanks

Reply #16 –
Quote from: Lon and Cheryl –
Great to have all the part numbers and sources listed in this thread.
How many of each are required?
Is it only for the front?
THANKS!
It will depend on year and model of your coach. Best to look at your air schematic, or crawl under and look.
Mine has a protection and check valve on each dry tank, but yours may be different.
Jim C.
coachfree, previous 1997, 1999, 2000, and 2003 Foretravels.