MC8 Treadle valve leak

[Zrob90sc]

Hey guys, Im having an ongoing leak from the treadle valve exhaust.  Bought the bus and drove it home with it leaking.  Got it in my shop and tore into it, started by replacing the pp1, then replaced the inversion valve, then rebuilt the DD3's and the leak hasnt changed.  About 3psi per minute.  All parts came frome luke.  All brakes are adjusted and working as they should. Starting to suspect the treadle valve itself.  Am i missing something?

[buswarrior]

Yes, the treadle valve is a wear item.

to confirm the air is not coming from elsewhere, disconnect the output lines first, and with only the supply line left connected, confirm the continued presence of the leak, or that it is coming out of one of those disconnected.


happy coaching!
buswarrior

[Zrob90sc]

Thank you, turns out the treadle valve was leaking internally!  Replaced it and that leak is gone, onto the next.