Lift - General Operation Question

[maxwell99]

When i park the old TO-35, 1957 model,
if i have an implement on the 3 pt hitch, I always let the implement down and take the weight off the lift systen valves.

Question: is this procedure really necessary?

It was my understanding that the valve holding the implement in the up position could stick and the next time you moved the lift lever to the down position, the implement might stay in the up position.

any truth to that and is that the proper way to leave the lift in the down position when you park the tractor?

Thanks, just trying to take care of my 55 year old tractor.

Note: even when i leave the lift in the up position the lift arms will leak down in a while so the implement will be on the ground in a hour or so, but was just afriad the lift valves could stick.
 

[Inno]

I'm pretty sure that even in tip top shape the system will drain down 15-20 minutes after use anyway. I think John(UK) has said this is normal. Can't see anything else sticking as a result of leaving the lever up as the valve on the pump is bathed in oil. The only thing might be the lever itself and I would think it would take a VERY long time to seize up. The levers on my 202 were seized completely but I think it's because they hadn't been used in decades as the backhoe was alway in place on the back.
 

[samn40]

Much, much safer to do what you are doing. Keep on practicing safety first. It doesn't really matter to the mechanics of the tractor either up or down, anyway the tractor can be repaired....children are more difficult to repair!
Sam
 

[Inno]

Excellent point.
 

[phil(va)]

Not just children. Pets too.
 

[John(UK)]

Unlikely that the non-return valves will stick unless the system has water in it and they will rust or the springs rust and break. The Control Valve can stick when it is worn if you do park the tractor with a load on the 3 point and with the Engine stopped. When the Engine is running the Control Valve is rocked from side to side in an effort to prevent sticking. While there shouldn't be a load on the control valve because of the non-return valves (8 of them) holding the pressure, if these get worn, as they do, there will be some pressure leaking and that will hold the Control Valve. Why park with the 3 point in the raised position anyway, it can be dangerous should someone move the Control Levers (children?)and the implement will crash down.The hydraulics were never designed to hold up indefinitely as there is no need for this. The leak-down you get when you do park it with the implement raised is from various parts of the system and it is just wear and tear, but when the Pump is running it will be more than capable of taking care of small leaks like that. Usual places to leak are the Lift Cylinder and the non-return valves and the Control Valve in the Pump. There is nothing to prevent you parking the tractor with an implement attached in the raised position, but if the Control Valve sticks, it doesn't always free-off very easily, so the easy way is to lower the 3 point when you park the tractor. I have attached some pictures of the Control Valve and the Non-return valves(12-17)..the vertical "lines" on the control valve are washer or spacers that separate the different pressures in the Pump, these do wear with the continual sliding action of the Control Valve, so the holes get bigger and allow pressure to leak. These valves are a precision fit but do wear over time and dirty oil definitely does not help.
It does say that you should always lower the 3 point when parking in some versions of the operators manuals. Why don't you like the idea of lowering the 3 point each time, it would be interesting to read your view on this....John(UK)....fergusontractors@hotmail.com


 

[John(UK)]

Something I should have also said yesterday. If the hydraulics take so long to drop down, there isn't much wrong with them. You will often find that they will visibly drop as you look at them....John(UK)....fergusontractors@hotmail.com