Hydraulic lift sticks

Sounds to me like the control valve is sticking in the pump and not moving as much as it should. It is probably some foreign material that got disturbed when you were working on the lift. I would try to rinse out the pump housing by pouring about 2 gallons of kerosend through the pump housing 2 or 3 times and each time letting ti settle so that any solids can drop out of the kerosene and be poured off and not put back in. When it is pretty clean then replace with new oil. 134 since you have the new type piston rings now. Take off the right side inspection plate and after the oil is replaced start the tractor and with your hand move the control rod back and forth till it is free. This usually will do the trick. If it has scored the control valve and continues to stick you may have to pull the pump out the bottom and remove the control valve and using some 400 grit sand paper polish it and put it back in with some oil on it and see if it is free moving now.

To elaborate on the above----- /
Message Added: Re: HYDRAULICS STUCK ON 8N-----PLEASE HELP!!!
The following information was added to the message board: Name: ZANE
E-Mail: wzsherman@aol.com
Subject: Re: HYDRAULICS STUCK ON 8N-----PLEASE HELP!!!
Body of Message: You have a sticking control valve. This can be a combination of problems. The first thing that can cause it to stick is dirty oil. The N hydraulics has no filter system and any and all foriegn material that enters the differential, transmission or the lift settles in the lower reaches of the lift. Unfortunately that is the home of the control valve and oil intake too. The best thing to do to remedy this dirty problem is to pull the pump out of the tractor and clean it. The other thing you can do is to drain all three places and rince the lift out with 5 gallons of kerosene. Pour it in as fast as you can through the inspection hole. Allow it to settle for a while and then pour it through again leaving the residue in the bottom of the container and discarding it. Do this untill no residue is in the bottom of the catch container. Add new oil. If you do take the pump out you should take the control valve and spring out of the pump and inspect the control valve for any wear patterns that might make it want to stick. The control valve can be polished by turning it in some wet or dry 300 grit sandpaper to smooth out any imperfections. This will make the vavle fit a little looser in it's bushing but if you don't get too carried away at it the difference in size will be inconsequential. The return spring that pushes the control valve back to the unload position can break or become weak from age and fatigue. Make sure it has enough tension to do a good job of pushing the valve back. If it is too weak the valve will not come back to the unload position with a heavy load on the lift no matter how clean or good fitting the valve is.