Air Brake Protection Valve leaking/venting

[Andyrv6av8r]

The wife was driving Shrek this weekend with yours truly riding shotgun (a normal scenario). We noticed that the air was bleeding down pretty fast at long traffic lights as the brakes were held, so I had a look when we got home. I found that air was venting pretty heavily out of the front Service glad hand vent and the Air Brake Protection Valve on the frame over the rear axle. After some troubleshooting and talking to Suprman ( Thanks Will! ), I found that the check valve for the front Service glad hand had debris under the diaphragm and the Air Brake Protection Valve had a crack in the rubber disc on top that acts like a check valve. After some quick cleaning and repairs, all is well and Shrek holds air like normal. It amazes me sometimes how simple problems can be such a headache to find and bring things to a halt.

 

[Andyrv6av8r]

Sorry about those 2 random sideways pictures.

 

[Lmtv772]

great post. helped me a lot

 

[Retiredwarhorses]

I have the same problem...where did you get the new little diaphragm?

 

[Retiredwarhorses]

I see there are 3 chambers...I assuming they are all the same size...I will repalce them all, quite simple and can be done wile protection valve is still on the truck, mine fell to pieces when I removed it.

 

[Ue413]

I've got a similar sounding leak, and have been checking check valves and other valves all over the truck with no success yet. Did you notice the leak only when you had the brake pedal depressed, or was it when you disengaged the parking brake as well?

if I air up my truck and then shut it down and release park break....the front emergency glad hand leaks.

 

[Andyrv6av8r]

My leak was when the brakes were being held, like at a traffic light. You could hear the air venting over the running truck and watch the air gauge drop.

I've got a similar sounding leak, and have been checking check valves and other valves all over the truck with no success yet. Did you notice the leak only when you had the brake pedal depressed, or was it when you disengaged the parking brake as well?

if I air up my truck and then shut it down and release park break....the front emergency glad hand leaks.

 

[Andyrv6av8r]

http://www.ryderfleetproducts.com/h...kit-for-tractor-protection-valve-p-u55-rn31bc

 

[Retiredwarhorses]

http://www.ryderfleetproducts.com/h...kit-for-tractor-protection-valve-p-u55-rn31bc

Thank you, I see Napa sells that same kit...on the flip side, I bought an entirely new TPV off epay for 45.00 last night.
Will advise if it fixes...but it's same issue you had.

 

[Retiredwarhorses]

All fixed....this part did the trick.

 

[tokarev]

Having the exact same problem with the rear valve - thanks for the parts info too.

 

[kenet3621]

Once Andyrv6av8r pointed me in the right direction, I got the Haldex RN31BC kit here...

https://www.finditparts.com/products/370234/haldex-rn31bc

 

[FloridaAKM]

Same problem here, Haldex parts fixed the problem & stopped the big time air leakage. Now the brakes work like they are supposed to.

 

[kenet3621]

Here is the old diaphragm that was in the TPV (Tractor Protection Valve). Easy to see it was totally wasted...


New one installed in less than 10 minutes. No more leaking of air! Pressing on the brake pedal and no loss of air pressure in front or the rear systems.

Again my thanks to Andyrv6av8r !

 

[Reworked LMTV]

The wife was driving Shrek this weekend with yours truly riding shotgun (a normal scenario). We noticed that the air was bleeding down pretty fast at long traffic lights as the brakes were held, so I had a look when we got home. I found that air was venting pretty heavily out of the front Service glad hand vent and the Air Brake Protection Valve on the frame over the rear axle. After some troubleshooting and talking to Suprman ( Thanks Will! ), I found that the check valve for the front Service glad hand had debris under the diaphragm and the Air Brake Protection Valve had a crack in the rubber disc on top that acts like a check valve. After some quick cleaning and repairs, all is well and Shrek holds air like normal. It amazes me sometimes how simple problems can be such a headache to find and bring things to a halt.
View attachment 579184 View attachment 579185

What was the part # for your unit? I know there are different TPVs.

 

[Andyrv6av8r]

It's in post #12 above. Haldex RN31BC