Dump valve

[richard5933]

Our new 4108 has an electrically operated pneumatic dump valve setup. Works from a switch next to the driver.

Outlet is a cast iron fitting. There is a hose with a screw on matching fitting, but I can't see this being easy to use or all that desirable.

Any one have thoughts on converting this over to something more modern? Looks like the cast iron is only 2".

1974 GMC P8M4108A-125 (Current bus)
1964 GM PD4106-2412 (totalled Sept 2017)
Located in beautiful Wisconsin
KD9GRB

[TomC]

Simply cut off the pipe after the valve and use an ABS 2"-3" with hose clamp and rubber hose to use a standard RV type hose. Then just add another switch to the compartment right there. With the tank being plastic, you could change out the whole setup

[Oonrahnjay]

       I don't know anything about it, but it looks so "agricultural engineering" complex that I can't help but love looking at the photos!

[luvrbus]

Back in that era most dump stations like at F/J had a open grate dump I miss those, you drove over the grate and flipped the switch no hoses to contend with, lol those days are gone thanks to people making a mess and leaving it 

[edvanland]

Still have one at Lake Powell at the Shell station car/bus wash. They have a lot of tour busses.

[luvrbus]

Still have one at Lake Powell at the Shell station car/bus wash. They have a lot of tour busses.

To far for me to drive Ed to dump but those nice aren't they 

[gumpy]

Still have one at Lake Powell at the Shell station car/bus wash. They have a lot of tour busses.

I understand there are a couple in Chicago over the river, too. 

[windtrader]

What? them grates are everywhere, every street has them, hardest part is getting lined up over one to keep the toilet paper from hanging up in the grate.

[Rick 74 MC-8]

 My MC-8 was converted by executive coach in 74 it also had a Dave Matthews valve on the curb side in addition to the standard dump on the street side.

[PP]

I like the brass valve setup. If it works, I would just figure out a way to put a standard valve and hookup after it and use it for holding back the blackwater, (the water with the chunks in it  ). That way when you're parked for a while you can leave the grey valve open and just dump your blackwater every few days and not risk building a pyramid of doom in the tank.
Will

[richard5933]

I like the brass valve setup. If it works, I would just figure out a way to put a standard valve and hookup after it and use it for holding back the blackwater, (the water with the chunks in it  ). That way when you're parked for a while you can leave the grey valve open and just dump your blackwater every few days and not risk building a pyramid of doom in the tank.
Will

That's my plan... I just need to figure out how to add a modern connection to the cast iron. Not much room underneath, and I'm afraid of doing anything that lowers it more.

No gray tank on the bus. Just fresh and black. Both probably 100 gallons or more. With the smaller outlet on the black tank, being combined is probably a good thing. Otherwise, it wouldn't have enough liquid to push everything through to opening.

Is there a 'standard' method of connecting a modern sewer hose fitting to the cast iron?

1974 GMC P8M4108A-125 (Current bus)
1964 GM PD4106-2412 (totalled Sept 2017)
Located in beautiful Wisconsin
KD9GRB

[kyle4501]

I would look for a pvc thread to socket weld adapter. Screw it on to the pipe & glue a piece of pvc pipe in to it & then glue on the hose adapter. 

[eagle19952]

i'm not sure i'd sacrifice that much ground clearance for a poop pipe. 

[richard5933]

What about replacing the cast iron nipple sticking out the bottom with something like this? I can then install the appropriate coupler to the hose  to make it flow.

Richard

[luvrbus]

I would cut it off and use a Fernco coupling and go to the standard RV setup simple and easy