MAJOR air "leak" in air brakes - '94 Holiday Rambler

[SteveD]

Searched the forum(s) and didn't find any reference to a leak like this one. When I apply the service brakes, I have TONS of air escaping from the rear manifold next to to the differential. It's leaking out of the line that connects between that manifold and the left rear brake actuator. The fitting at the manifold has a HOLE that is releasing the air. I'm not really sure how long this has been happening since I've just started TESTING the various parts of my air brake system after I found a HOSE leak due to squirrel intervention.

There is an OPEN line of some sort coming from the top of that same manifold - it's about 18 or 20 inches long and appears to be 'broken', but I can't find any place that it might have once been attached to ... a vent of some sort? Have seen no air going into or out of it, but I'm sure I haven't checked all possibilities of brake configuration/actuation. That open line just happens to be about the right length to reach the place where the leak is .. but I don't really think they ever connected to each other.

Here is a picture of the HOLE where the air is leaking
The HOLE is in the end of the fitting indicated by the red circle. When the brake pedal is pushed, air blasts out of this hole. I'm not sure if this is a pressure release valve of some sort .. or maybe a broken line ... or whether it's NOT supposed to be OPEN. It seems to be some sort of special fitting, but I have no clue what it is or how it's supposed to work.

I welcome any input as to the purpose of this fitting/valve/connection .. whatever it really is.

The brakes DO "work", but I'm pretty sure there is a LOT of air being lost here that is not supposed to be. I'm pretty sure it didn't used to leak that badly (I've had this RV since '07). I can hear it clearly from the driver's seat now, but that's without the engine running. Not sure I would ever notice it with the engine noise. And I don't guess I've ever had someone pushing on the brake while I was around the back of the RV where I might hear it.
HELP ,
Steve
PS.. maybe I should also mention that I recently found my AIR DRYER to be non-functional and rebuilt it and have flushed the main air tanks. PROBABLY not related, but thought I'd mention it since it's related to the air system.

[t55watson]

I don't know for sure but it sure looks like it was connected to a very small diam. line which would indicate a warning light or some sort of sensor.

[SteveD]

FWIW, I took the fitting off and, sure enough, it was obviously the nut for a 1/4" air hose .... which was the broken one from the top of the other half of the assembly. I wish I knew more about the function of each, but connecting the 2 ports back together solved the HUGE air leak problem. The air has now been up on the coach for the last 3 hours or so and there is no measurable (or HEAR able) leak when the pedal is pressed except for the initial drop in the first second or 2.

One more thing I can check off my list, thankfully... assuming the brakes actually WORK the next time I move the RV .

[dennis45]

Originally Posted by SteveD

FWIW, I took the fitting off and, sure enough, it was obviously the nut for a 1/4" air hose .... which was the broken one from the top of the other half of the assembly. I wish I knew more about the function of each, but connecting the 2 ports back together solved the HUGE air leak problem. The air has now been up on the coach for the last 3 hours or so and there is no measurable (or HEAR able) leak when the pedal is pressed except for the initial drop in the first second or 2.

One more thing I can check off my list, thankfully... assuming the brakes actually WORK the next time I move the RV .

Sounds like your on your way. Thanks for the update. Have you thought about having someone press the brake pedal while you confirm the rear brakes are activating?

[SteveD]

Originally Posted by dennis45

.. Have you thought about having someone press the brake pedal while you confirm the rear brakes are activating?

Have THOUGHT about it, but I'm here by myself today.. That test will have to wait for another day.

Besides... I'm tired now
Steve

[dennis45]

Originally Posted by SteveD

Have THOUGHT about it, but I'm here by myself today.. That test will have to wait for another day.

Besides... I'm tired now
Steve

I can relate, it's Beer Thirty,,,,

[Ray,IN]

It's a sound practice to test your air brake system every day you use your MH.
AIR BRAKE TEST VIDEO
Air brake testing cheat sheet to print and place in MH. Source: http://www.myrv.us/Pgs/RV/Air_brake.htm