BCM Community

Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: belfert on September 18, 2010, 06:48:56 AM

Title: Can any help identify this brake treadle valve? BW 574788-C91
Post by: belfert on September 18, 2010, 06:48:56 AM
I am trying to find a manual or something for my brake treadle valve.  Manufacturer is listed as BW which I think is Bendix.  The part number is 574788-C91.  I can't find anything on the Bendix website under the whole number or just 574788.  I also checked the spreadsheet from Bendix that shows their part number conversion from 2007.

I am trying to determine what all the unused ports on the sides of the valve are for.  There has to be one that delivers air to the brakes I can use for my sensor.  There are probably unused ports on the back of the valve too, but the steel wall behind the valve only has holes for the ports the manufacturer of the bus used.

Thanks in advance for any help.
Title: Re: Can any help identify this brake treadle valve? BW 574788-C91
Post by: belfert on September 18, 2010, 07:19:56 AM
It looks very much like an E-7 or E-14 from Bendix.  There are many, many part numbers for these, but nothing that matches.  I'm going to compare the photos I got from Bendix with what I have.
Title: Re: Can any help identify this brake treadle valve? BW 574788-C91
Post by: belfert on September 18, 2010, 09:05:30 AM
I keep replying to myself!

I have determined beyond a doubt that this is an E-7 valve.  The body of the valve matches the photos from Bendix exactly.  I also pulled one of the plugs from a port labeled as delivery in the diagram and it does indeed seem to be a delivery port.
Title: Re: Can any help identify this brake treadle valve? BW 574788-C91
Post by: rv_safetyman on September 18, 2010, 11:56:47 AM
Brian.  That number looks like an IHC number from my old days with IHC belts. 

Not sure that it matters.  The E-7 information should be pretty generic. 

If you have the valve out, I would put a compressor on it and test the ports.  It should be a dual function (not sure of the technical term) where the front and rear have separate systems within the valve. 

If the valve is still in the bus, you can simply air it up and remove a plug and install a pressure gauge in that port and see what happens when you apply the brakes.  I would bet you will hit a port you can use on the first or second try.

I am assuming that you are hooking up the trailer brake system.  For that, you could select either front or rear system. 

Jim