Farmall M Hydraulics Question

We have a 1951 Farmall M that belongs to my wife's dad. There are some connections which I assume must be for a hydraulic system, but which he has never used. Hope someone can tell me what we have here and, assuming it is a hydraulic system, what I might need to do in order to get it working. Description as follows;

On the left side of the tractor just below the starter and behind the clutch lever, there are what appear two hydraulic connections located side by side, both fitted with 1/2 inch elbows. The front elbow connects to a 12" length of hydraulic hose that is stubbed off. The back elbow is plugged and can be rotated by hand, although it doesn't seem to unscrew.

On the right side of the tractor near the pulley there is a fill cap located on the top surface and below that on the side, a lever and another 1/2 inch elbow plugged off.

I have photos showing the items described above If that would help.

Hope someone can shed some light on this as I know very little about hydraulics.

That is the standard lift-all system. It is a very basic transmission-driven (non-live) hydraulic system, meaning that your foot must be off the clutch pedal in order for it to work.

It is a one-way system as you see it. Power up, gravity down. You can add a two-way valve to make it two-way.

The front elbow on the left and the elbow on the right are the main pressure ports. They operate at the same time. Each one would normally be connected to one cylinder on a loader or a cultivator.

The rear elbow on the left is a delayed pressure port, meant for lifting the rear section (wheel-track scrubbers) of a cultivator.

The lever has three positions. Back is for lift, middle for hold, forward for lower. The lever may also be locked back if you are using a two-way valve.

i hooked up the connections right out of the pump to my front loader i got up,hold, but down is fast it just drops hard and hits the ground is that normal i tried to push the lever gently but still hits the ground hard what could be wrong with it.

i forgot 49 Farmall m using the lift-all pump

Slow release can be tricky, especially if the loader is full of heavy stuff. Put your thumb and the side of your index finger on the control rod and against the support bracket. Push the control rod forward with the palm of your hand, while controlling how much it moves with your thumb and finger. It will take a little practice, but on most of those old lift units, you CAN make them come down slowly. Another option is to install an adjustable flow restricting valve in each line.

IH made a check valve with orifice for this problem they came from factory on mounted cotton pickers and could be added for any heavy implement. I have one of the valves on my 3 point hitch.

Thanks for your explanation of the Farmall M hydraulic system. Now I have several more questions;

1. Since this is a one-way system, I assume the right and left hydraulic ports connect to two seperate cylinders. Both cylinders would raise by hydraulic pressure and lower by gravity?

2. In taking a closer look, I noticed there is a 1/2 inch threaded connection just below and slightly to the front of the right side hydraulic connection. It appears to be plugged with dirt and grease. Any idea what this is for?

3. As for the hydraulic control lever, I'm not sure it's working properly. With engine off, the lever is resting in the forward position. Pulling it back towards the steeing wheel it pivots about 20 degrees until it hits a stop. When released it flops back to the forward position. I don't sense any stop or detent to hold it in the middle position. Is this normal?

4. What are the requirements for hydraulic fluid, how much and what is the proper fill level? Also, should the system be flushed before filling?

5. Is there a good way to tell if the hydraulic system is working without investing in lots of expensive equipment?

6. If adding a 2-way valve to make it a two-way system as you described, I assume that would mean hydraulic connections to both ends of the cylinder(s). If so, doesn't there have to be a return path from the 2-way valve back to the reservoir and if so, how would this be implemented?

The rod that controls the Liftall passes through a slot like cast arm on the steering post. This bracket is used to hook the rod in the hold position. The small welded on stop on the under side of the rod is hooked on the slot in the bracket. (there is supposed to be a flat spring on the bottom of that slot, that holds down on the rod but many are broken) The rod pulls farther to lift, and back to the stop to hold, and lifted and pushed farther to lower the load.
I am concerned about the rear left outlet. It should be able to be tightened into the housing (inside) to prevent leakage. it is just Pipe thread. If turning it CW never tightens it, the pump will need to be removed to fix the threads.
It is under pressure when the rod is pulled (delayed, but still pressurized. The pump comes out easily (but awkwardly) out the bottom. The cover plate is removed, the cotters in the pump drive shaft removed, then the drive shaft. The pipe fittings and cap and lever are removed, and the 4 bolts holding it up are loosened, not removed until ready. The pump is heavy and needs a floor jack, and two people to lower it. Threaded rod in the bolt holes and nuts to lower it are slower, but safe. JimN