Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: goldbehen on August 14, 2019, 02:05:07 pm

Title: Parking break switch leaks all my air when pushed in
Post by: goldbehen on August 14, 2019, 02:05:07 pm
Sitting in the middle of the Adirondacks with an air brake problem. I can air up to level and the travel light comes on.but when I push the switch in to release the brakes air starts leaking out.  It sounds like it may be coming from the switch itself but not positive. As I said the level works and the coach airs up until the switch is pressed in. Any ideas on how to trouble shoot this? Is it possible to bypass. Hope someone can advise cause I'm 30 miles from the nearest small town(saranac lake).lucky we're here for the next 9 days.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: craneman on August 14, 2019, 02:11:06 pm
The seals go bad in the air release. They are available at most truck stops. If your air is staying above 90 psi with the leak go ahead and travel to where you can buy one. This advice is only if it is leaking at the release valve because it can't be bypassed. If you find the leak somewhere else get back to us with the new info.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: goldbehen on August 14, 2019, 03:08:15 pm
That could be it. It won't stay above 90 so I guess I need to get a seal. Is there a specific seal size and is there a diagram that shows where it goes. Sounds like something I can do.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Dub on August 14, 2019, 03:15:56 pm
You need a valve, you can replace it with minimal hand tools.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: hdff on August 14, 2019, 03:17:15 pm
I'm sure google or YouTube would be your friend right now. Good luck
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Dub on August 14, 2019, 03:26:16 pm
Raise the dash lid and look down or get on the floor and look up, whichever one gives you the best view and access to it.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: craneman on August 14, 2019, 03:26:27 pm
here is one

Amazon.com: Truck Trailer Air Brake PP7 Dash Control Valve: Automotive (https://www.amazon.com/Truck-Trailer-Brake-Control-Valve/dp/B0028OBPYG)
Title: Re: Parking break switch leaks all my air when pushed in
Post by: CRY42 on August 14, 2019, 03:54:18 pm
Had the same problem, but, it was the SWITCH on the bottom of the Air Valve leaking.
Replace both due to their age, but just a thought.
Good luck and safe travels.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: goldbehen on August 14, 2019, 04:53:00 pm
Is the switch integrated into the valve?It looks like the part Dub linked will replace the entire valve switch. It does look like what I've got. Do I need to order more than the valve replacement? Also how do I detach and reattach the small airlines?
I'll see if I can YouTube as well. If this works I owe you all a couple beers.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Chuck & Jeannie on August 14, 2019, 04:54:24 pm
My parking brake control rebuild thread should help you out:

Bendix PP-1 Repair Kit (https://www.foreforums.com/index.php?topic=27892)
Title: Re: Parking break switch leaks all my air when pushed in
Post by: goldbehen on August 14, 2019, 06:14:53 pm
Thanks for the link. The link to amazon was also helpful.maybe I can order through the local Napa store? Tupper lake has one 20 minutes from here. Amazing timing as we were backing into our camping spot after a 450mi trip when the valve failed. No warning .
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Dave and Nancy Abel on August 14, 2019, 06:28:14 pm
We replaced our Brake Release with this:

Parking Brake (Yellow Knob on dash)
Haldex 20021 dash parking brake release valve.

Valve Dash PP1 Hand Operated Push-Pull Parking, KN20021, Haldex (https://www.ryderfleetproducts.com/haldex-kn20021/valve-dash-pp1-hand-operated-push-pull-parking-p-u55-kn20021)

Good Luck, Dave A
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Travelin' Man (RIP) on August 14, 2019, 06:33:16 pm
maybe I can order through the local Napa store?

Yes you can.
I drink Bud Heavy.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Old Toolmaker on August 14, 2019, 07:10:38 pm
You might want to explore Saugerties, NY.  If you're lucky you might find a fantastic family owned Italiian restaurant.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: goldbehen on August 14, 2019, 07:50:12 pm
I'll keep saugerties in mind on the way home. We're about 90 miles south of Montreal. Maybe 30 mi from Lake Placid. Plattsburgh is up the road and might have some truck part supplies. I'll check the local Napa in the morning. They close at 5pm.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Old Toolmaker on August 14, 2019, 08:37:58 pm
I used to motorcycle tent camp in Schroon Lake, NY and for decades the spring opener was the Rhinebeck Antique Car show at the Duchess County fairgrounds.  That's local to Hyde Park, NY and the Vanderbilt and Roosevelt homes along with the FDR Presidential Library.  Not to forget that Rhinebeck, NY is home to Cole Palen's Rhinebeck Airdrome, where I understand, they're getting back to flying the original WWI airplanes.  You're in a great part of the country.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Michelle on August 14, 2019, 09:19:13 pm
You might want to explore Saugerties, NY.  If you're lucky you might find a fantastic family owned Italiian restaurant.


I'll bet you we've eaten there  ;)
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Phranc on August 14, 2019, 09:45:21 pm
Take the valve out and jump in the toad . FleetPride has locations in Plattsburg and Burlington Vt. Call ahead .
  Do a google search for FleetPride address. Get an exact replacement . Should be easy peasy.
    Of course there will be many other good parts locations also . Not a hard part to source
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Old Toolmaker on August 15, 2019, 01:48:57 pm
I'll bet you we've eaten there  ;)
Would that be the somewhat quirky family owned restaurant? 
Title: Re: Parking break switch leaks all my air when pushed in
Post by: goldbehen on August 15, 2019, 06:07:29 pm
Any suggestions for getting the yellow knob off the shaft.  Looks like some type of compression pin. I don't see any obvious way to get it loose. Appreciate all the help so far.I ordered the haldex valve from Napa. Should be in tomorrow.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: craneman on August 15, 2019, 06:46:19 pm
It's a roll pin, drive it out with a punch or grind a nail point flat, and use it.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Old Toolmaker on August 15, 2019, 08:16:55 pm
Any suggestions for getting the yellow knob off the shaft.  Looks like some type of compression pin. I don't see any obvious way to get it loose. Appreciate all the help so far.I ordered the haldex valve from Napa. Should be in tomorrow.
Buy a set of punches.  And you need something solid to support the other side of the shaft.  I, personally, am way too old for makeshift tools.

https://www.napaonline.com/en/p/AIT70557

Title: Re: Parking break switch leaks all my air when pushed in
Post by: Protech Racing on August 16, 2019, 03:29:26 pm
Use a  small socket on extension , clamped in vise for a backup.  Cut the  pointy end off of an appropriate nail . Tappy tap .
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Mogan David on May 11, 2020, 04:17:05 pm
I've read a number of threads about these air brake parking valves.  This seems to be the most recent. 
On my way back to MI from FL, last month, my park brake valve suddenly began HISSSSIIING loudly when I released it after fueling. 
I was able to drive without having problems with level system or brakes.  The hissing stopped whenever park brake was applied.

Back home, I ordered valve number H-3158 x-ref KN20021.  It seems to be like the one that blew a seal, which might have already been replaced since 1999.  When my local mechanic replaced the valve last week, he said the attached electric pressure switch (for instrument panel indicator) was also leaking, albeit much less than the actual valve was.  It is on order.

I ordered the valve rebuild kit Haldex 281126K so as to rebuild the replaced valve.  I managed to get the back cap off, although I didn't have any sort of spanner to fit the three notches in the threaded back cap.  Now I can't figure out how to dismantle the pieces and parts from the spring-loaded shaft.  There is no exposed threaded area.  In fact, I can't see the nut at all.  can't see what is holding the rubber disc sort of thing (with metal hub) in place.  It is the part on the end of the shaft farthest from the yellow knob.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: craneman on May 11, 2020, 04:43:17 pm
Post a picture. I have replaced parking brake seals on several different parking brakes, need to see which one you have.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Chuck & Jeannie on May 11, 2020, 04:56:59 pm
Now I can't figure out how to dismantle the pieces and parts from the spring-loaded shaft.
If the valve you are trying to rebuild is not original Bendix, then it might be different construction inside.  The rebuild kit may not work?

Link to my thread below where I rebuilt our original PP-1 valve.  The photos of the my disassembled valve might help you, or not.

I don't remember there being anything tricky about taking it apart, but it was 4 years ago, so...

Bendix PP-1 Repair Kit (https://www.foreforums.com/index.php?topic=27892)
Title: Re: Parking break switch leaks all my air when pushed in
Post by: MarkC on May 11, 2020, 09:15:31 pm
Have a question on the PP-1 Brake Valve.  I was going to order a valve to keep as a spare.  I see they have 20, 40, and 60 PSI available.  Anyone know what PSI valve is correct ?
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Chuck & Jeannie on May 11, 2020, 10:52:58 pm
I see they have 20, 40, and 60 PSI available.
Mark,

I am pretty sure 40 PSI is the correct parking brake "automatic set" pressure on Foretravel coaches.  I know I have seen that documented some place, but I can't recall where off the top of my head.  When tested (on our coach) the knob pops out at about 35-40 PSI.
Title: Re: Parking break switch leaks all my air when pushed in
Post by: "Irish" on May 11, 2020, 11:46:08 pm
Believe that 40 lbs is the standard most trucks use, if pressure drops below 40 the emergency spring brakes are activated, stopping the vehicle. it can be a lower setting as low as 20 lbs but 40 is what most air brakes are set at. The air pressure holds the parking in the off position pushing against the springs that are trying to close all the time. If it's set at 60 lbs you may under heavy braking (with air leaks and a bad compressor) loose enough pressure to bring on the emergency brakes for a very sudden stop, not a good scenario.
So, it's probably a 40 lb

Title: Re: Parking break switch leaks all my air when pushed in
Post by: Mogan David on May 12, 2020, 10:12:42 am
(https://www.foreforums.com/Users/markdezwarte/Desktop/IMG_1154-1.JPG)
(https://www.foreforums.com/Users/markdezwarte/Desktop/IMG_1153.JPG)
well...
that didn't work...
have to figure out how to attach photos

Chuck,  thanks.  I had seen those photos before I posted.  Your valve is different.  When rear cap is removed from it, the threaded end of the shaft, with lock nut, is right there.  When the rear cap of mine is removed, I'm looking at the rubber disc.  thought it might pop off with an O ring removal tool.... NOT
MPParts | Haldex KN20021 Parking Brake Valve | KN20021 (https://mpparts.com/part/haldex-kn20021-parking-brake-valve-with-kn20903-yellow-knob-kn20021)

The kit:  Haldex Reman Valve Repair Kit - 281126K (https://www.jittruckparts.com/brake-valve-repairkit-pp1-281126k?gclid=EAIaIQobChMIzMf0yNGH6QIVRtbACh1P2QhjEAQYAiABEgLkNvD_BwE)
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Keith and Joyce on May 14, 2020, 04:11:50 pm
How to find a leak.

1: Put soapy water on it and watch for bubbles

2: Get a length of plastic tubing.  Put one end in your ear put the other near where the suspected leak is.  It works.

3: Buy one of these:
Air and gas leak detection set in a case - LD 400 (https://www.cs-instruments.com/products/d/leak-detection/ld-400-leak-detection-set-in-a-case)

Little over the top but then who am I to criticize as I have one!

Keith
Title: Re: Parking break switch leaks all my air when pushed in
Post by: Hans&Marjet on May 14, 2020, 04:29:17 pm
"Snoop" is great product....