M hydraulics

[Ken-Mt]

ITT manual was no help-this is how the belly pump on an M works-correct me if I"m wrong.RH side of tractor-fitting down on side is return.Pressure comes out top of housing which is a "T"-top port in "T" goes to breather cap,side port in "T" goes to an elbow to which a rod acuated control valve[w/ pressure relief] is attached.[off-on only]
My dad"s M doesn"t have the valve on top-it"s got a hose from the pressure "t" to a remote valve.Extra hoses,ugly valve,etc.I can"t seem to find an oem replacement valve but I found a 20 gpm single action lever controlled valve for $100.It has an adjustable relief that comes pre-set at 1500 psi.Would this work? Also,would this eliminate the breather spewing oil? I"m wondering if the relief pressure on the valve he"s using now is set to high and back-pressuring the breather.

 

[armand tatro]

Are you using the pump in the belley of the tractor or do you have a live pump mounted ahead of the dist.? A couple of pictures and more information would help. Thank you. Armand

 

[Janicholson]

Assuming standard "M" Liftall belly pump, not live hydraulic pump near the distributor or mag):
The right hand side port is pressure. The left hand front most side port is the same pressure (effectively a "T" on the inside)
The left rear side port is delay lift (usually no use, leave plugged) the return is normally through the same hose that provided pressure (one way push, gravity or spring return).
The valve you refer to makes it a two way system. This requires the lift lever to be pulled back and held, or wired in place to allow full time pump output (when the clutch is out)
The right side port pressure goes to the valve (Called a Christmas Tree in IH user's terms)
The valve is open center, and allows fluid to go immediately back to the reservoir. (ON yours it is the hose in the "T" at the cap. which needs to be a sealed cap if you are using 2 way cylinders).
It is better to route this return to a "T" in the drain plug in the bottom, avoiding flow and leakage at the cap.
The system will not generate enough pressure (normally between 650 and 800psi max because of a built in pressure relief in the pump unit) A pressure regulator set higher than 800 will not do anything, but will not hurt either.
No matter what,!!! the system needs to be open centered. Allowing all fluid to circulate to the reservoir when the levers are in center position, or not lifting. Look in parts and pieces (to the left under galleries) search for Janicholson H M This will direct you to diagrams.

 

[Dennis Stoeser]

The "T" on top you refer to is the fill port for adding fluid. The valve that sits on top of this(Christmas tree) is an extra option. The vent cap initially was the only thing on top. The fitting down on the right side is both the pressure apply and return. The lever on the side of the main case that actuates the pump output when pushed all the way forward will allow the fluid to return to the resevoir. The added valve simply alllows the use of a 2 way cylinder. Sounds like things got added incorrectly. Refer to those previously mentioned diagrams

 

[M Diesel]

(quoted from post at 13:32:16 01/23/10) ITT manual was no help-this is how the belly pump on an M works-correct me if I"m wrong.RH side of tractor-fitting down on side is return.Pressure comes out top of housing which is a "T"-top port in "T" goes to breather cap,side port in "T" goes to an elbow to which a rod acuated control valve[w/ pressure relief] is attached.[off-on only]
My dad"s M doesn"t have the valve on top-it"s got a hose from the pressure "t" to a remote valve.Extra hoses,ugly valve,etc.I can"t seem to find an oem replacement valve but I found a 20 gpm single action lever controlled valve for $100.It has an adjustable relief that comes pre-set at 1500 psi.Would this work? Also,would this eliminate the breather spewing oil? I"m wondering if the relief pressure on the valve he"s using now is set to high and back-pressuring the breather.

Just a extra note beyond what others have said: 20GPM is about twice what you need, so it would be fine. If valve is too big it can't be feathered very well is all. Too small however, and it will squeal like no tomorrow.

Pressure relief just says that I tried to send oil to hose but it won't take it, so I'm sending oil back to reservoir.