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Topic: now a hissing from brake pedal !correction! accelerator pedal (Read 918 times) previous topic - next topic

now a hissing from brake pedal !correction! accelerator pedal

Hey all!

Just replaced the brake air dryer the other day and checked for leaks, and all is good... except...

Now I have an air leak at the brake pedal.  I wound myself up in there, and it is coming from a cylindrical device that screws into the valve body, with a three-lobed plastic cap and a soft rubber split diaphragm in the center.  The air escapes through this diaphragm.  It is maybe a couple inches long, and smaller around than a quarter dollar.  I apologize for not providing a photo, but it is pretty tight in there.

I am guessing that this is a safety release valve, and that it should not be releasing when the pressure is 120 or below.  Could someone tell me if I am correct, what it is called, and where do I get one?

Matt B
1994 U-240
Matt B
1998 u-320

Re: now a hissing from brake pedal

Reply #1 –
Matt
www.brakesystemsinc.com
1-503-236-2116 
2221 N E Hoyt  Portland  Oregon
I replaced my base valve last year. part #wm90dx $118.11
Rick and Mary Zika
unit #4609
new full body paint by Foretravel of Texas
1995 U240 2014 jeep
The selected media item is not currently available."Rick and Mary"

Re: now a hissing from brake pedal

Reply #2 –
Source noted.  I am hoping the little piece can be replaced.  It looks like replacing the entire valve assembly would be a bit tough - lots of lines and not much room.

Matt B
Matt B
1998 u-320

Re: now a hissing from brake pedal !correction! accelerator pedal

Reply #3 –
Went back underneath with better light and pliers.  It is the accelerator pedal.  (repeat to self - this is not a car, this is not a car)  It apparently unloads through a vent, and the item I described is a dust cover - a diaphragm and nothing else, mechanically.

I moved the pedal a few times and the leak stopped - a piece of crud in the valve?

Matt B
haunted Grand-Zilla
Matt B
1998 u-320

Re: now a hissing from brake pedal !correction! accelerator pedal

Reply #4 –
Isn't spontaneous self repair great! We had a sticky brake light switch that was interfering with the cruise control and sometimes keeping the brake lights on after we parked. After I posted the problem on the forum, the brake light switches have performed flawlessly.
J D Stevens
1997 U295 CAI 36' Build #5085
2002 Subaru Outback
Motorcade 16869
Bellville, TX

Re: now a hissing from brake pedal !correction! accelerator pedal

Reply #5 –
Quote from: J. D. Stevens –
Isn't spontaneous self repair great! We had a sticky brake light switch that was interfering with the cruise control and sometimes keeping the brake lights on after we parked. After I posted the problem on the forum, the brake light switches have performed flawlessly.

Yes and no.  No repair needed, but I will be ducking and listening at the front of the coach for the next twenty times I drive it, fearing to hear the hissssssss.

Matt B
1994 U240, currently hissless
Matt B
1998 u-320