M915 air plumbing chart?? Somewhere?

[JH1]

I have a M915 that has had the later mods to add one or two air tanks that keep the transmission shifter happy with air, even if the other tanks drain down with braking. Problem: I can't find a chart that shows the current plumbing. I see several pictures of where lines go locally, but no one chart that shows it all at once, which is what is really needed to diagnose problems. Looked in the usual manual places. Any idea where to find it? Thanks. Jim

 

[Danl]

Danl M915A1

did you find anything on the air plumbing yet? if not there is a guy His name is Jayco or something close to that, he has a web page here on ss, look up lance robson he might lead you to Jayco he seems to know him well

 

[Bighurt]

Are you looking for where they route along the frame or where they are supposed to go as far as devices?

I don't think there is a defined path, from the MWO. Sorta just siad do it and they made it work so each truck will have slight variances in routing but they all should go tot he same device in the same order.

Try the M915A1 manual's. I believe they have the same plumbing as the MWO on the A0 trucks. Mine has at least 3 tanks, that I can recall off top of my head.

Or try dueceman51...he works them for a living.

 

[JH1]

Thanks, guys. What I'm looking for is a chart that shows what tank feeds what valve, through what color line, and so on. As to where they physically route, I can just follow them wherever they go. Mine has the mod that adds one or two tanks that provide dedicated air to the shifting tower that does not decay down due to braking. The way it's set up now, a problem condition can exist where you have the spring brakes engaged, and then also add the Johnny bar or foot pedal, creating a double force on the poor slack adjusters. There are some simple valve fixes to eliminate that possibility. I'd just like an air chart to refer to when making the mod. I'll share it here when it's done and tested. I have a friend who went to the Bendix air brake school to help me.
Jim

 

[Bighurt]

TM 9-2320-273-20

Identifies the components and their position, in chapter 2. Supply reservoir is dedicated to the tranny. Theory of operation is kind of ambiguous.