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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Steve102C3 on September 22, 2012, 07:06:04 PM

Title: Brake valve leaks at exhaust diaphragm
Post by: Steve102C3 on September 22, 2012, 07:06:04 PM
I replaced the brake valve on my 102C3 with one I ordered from Luke.

I had noticed the old one was leaking from the exhaust on the bottom of the valve assembly.

After replacement, the new valve leaked in the same way. My MCI maintenance manual doesn't troubleshoot this.

Is this normal? Is there another component in the brake system that could cause this.

Any ideas?

Thanks in advance,

Steve
Title: Re: Brake valve leaks at exhaust diaphragm
Post by: Dave5Cs on September 22, 2012, 07:31:56 PM
Call Luke . He will know if it is meant to operate that way.
Title: Re: Brake valve leaks at exhaust diaphragm
Post by: luvrbus on September 22, 2012, 07:43:29 PM
On the dd3 remove the center air line on the chambers one at a time if it stops you have a bad diaphragm on the opposite side from the one with the removed air line crazy huh
Title: Re: Brake valve leaks at exhaust diaphragm
Post by: Dlsnow on September 23, 2012, 04:56:11 AM
I have noticed that when I start the bus if i release the parking brake before the pressure is over 100 it hisses from under the driver seat and will let out all the air and it doesnt release the brakes.
Once they release they can be reapplied and released at normal pressure (90-120) without the leak/hissing)

Wondering if either of you had this experience before the leak?
Title: Re: Brake valve leaks at exhaust diaphragm
Post by: Dave5Cs on September 23, 2012, 03:49:13 PM
Disnow,

Thats what mine did when the purge valve on my Air dryer was stuck open. re-built it and it stopped.
Title: Re: Brake valve leaks at exhaust diaphragm
Post by: Steve102C3 on September 23, 2012, 06:16:14 PM
Thanks.

I will check the diaphragms & the air dryer.

Steve