Hydraulics will not lift tiller, now what?

in order to fix it, you must determine what's wrong.

I would first check the belt on the hydraulic pump, then the fluid. you might have an air blockage, but usually you can fart around and get some movement with it.

to check the pump, you can disco the pressure line and put the line in a container to see if you are in fact pumping fluid.

I've seen on old hydro equipment, the hoses can deteriorate and come apart on the inside and block oil passage...or worse if it gets to the pump.

Does it lift it at all? Does it just not raise far enough? You could have low oil level. Since the hydro pump runs the hydraulics on this model, and there is no separate pump or hydraulic system, low oil should affect it also. If the hydro is operating normally (moves smoothly forward and reverse), then it may be the hydraulic valve or the cylinder.

I find that on my 1256 I have to wiggle the lever around until I find the right spot to get the cylinder to fill to lift the tiller. I know I will be rebuilding the valve this winter to correct this.

Sounds like there are several options you can look into. Good luck!

Keep us posted as to what you find...it may help others in the future.

The suggestions are appreciated. More info:

The fluid level was topped off so it probably is not low fluid.
The fluid is very old, I topped it off with tranny fluid, but most of it is old.

Without attachments, the hydro pedal (not the lift valve) needs to be depressed very far for the tractor to start moving in forward or reverse.

The hydro is not silent but squeals in both forward and reverse.

Someone on another forum suggested replacing the filter. Indeed, it has the original in-line filter.

The lift valve is original and seems to work. I purchased a newer, cleaner lift valve from ebay. Perhaps the original is worn and allowing fluid to bleed.

Correct rod? - well, sort of. The bar from the cylinder lever to the tiller lever is too short. I lengthened it by bolting on an angle iron which has many holes along it's length - one of those constructo-angles from HD. I can adjust the length about 6 inches in 3/4 inch increments. However, it should lift a little bit. It does not. I can pivot up the tiller by hand (disengaged from cyl) so I know it can move.


So, this is what I will do before tearing into the hydro:
1. replace in-line filter with a screw-on setup from Tractor Supply cuz the in-line is expensive from Sam's Bolens (but not bad for a restore-to-factory condition)
2. remove and inspect all lines for blockages
3. drain fluid, inspect for crud, and refill with new universal tractor fluid (or ATF-F or whatever - I have no strong preference)
4. adjust all external linkages from the treadle-pedal to the hydro
5. run the hydro a little. drain a little fluid and check for remaining crud that was pushed through.
6. Adjust the pivot arms on the tiller 1/8 inch further apart cuz the freakin APE that assembled it made the arms too narrow and grind against the tractor receiving surfaces.

Try it again.

See, and here I was wondering what to do with my spare Saturday. Thanks guys!:thanku:

C2H8O said:

Steevo, you have my attention. What might the squealing indicate?

Click to expand...

It is just that squealing from a hydraulic pump usually indicates either a pressure relief valve by-passing or some similar escape of pressure.

In the Bolens (Eaton) hydro manuals, they all mention a defective charge pump as one of the possible problems when a lift will not lift.

If you haven't yet downloaded the correct Eaton (10, 11, 12) manual for your hydro, you should do so and read through it for all recommended steps in troubleshooting.

The hydraulic control valve (up-down control) may have a pressure relief valve on it, They generally look like a cap screwed into the main pressure path at the center of the valve, and have a spring-loaded plunger under them. I do not have a picture of a 1456 hydraulic valve to draw an arrow on, so unless you can photograph yours and post it, I don't know that I can provide any more specific direction to find it.
If the sound you hear when trying to raise the tiller sounds like a whine, or screech, and if it comes from near the control lever, rather than from under the seat (near the hydro), then it may be the relief valve.

The set screw on the side of the cylinder control is a pressure relief valve.

I confirmed it by taking it out. It has a hex-head, but the end is machined down to a fine spindle. The spindle goes inside a strong spring, which presses on a ball bearing.

When I cleaned the control valve, I loosened the hex screw, which lowered the relief pressure. I cannot test it now. I removed the inline filter and I am committed to replacing that with a spin-on setup. Once I have the filter in place and the system is filled with new fluid, I will crank down the relieve valve and re-test the tiller.

-DougL