MLV
04-28-2008 09:40:34
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Re: Hydraulic Lift Trouble in reply to Jeff-oh, 04-27-2008 17:47:33
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Jerry/MT said: (quoted from post at 04:31:21 04/28/08) Those tapings on the side are test ports. You can check the relief valve setting with them. You should not open them for what you are doing, however your observation of them bleeding off the pressure and the lift dropping is another clue to the puzzle.
Based on your description, I would suspect the control valve is binding. Get the hitch to the highest position, THEN SHUT OFF THE ENGINE.(NEVER PLACE YOUR HANDS IN THE HYDRAULIC COMPARTMENT WHEN THE ENGINE IS RUNNING!)
Place the control lever in the full down position and observe what happens. Then, reach over to the control fork and pull it toward the back of the tractor. Does the lift fall? If it does, you found the problem. The control valve is sticking. If it is and you are bleeding pressure from the test port and the lift drops, I"m pretty sure that your control valve is the root cause of your problem.
Changing the oil is not going to cure the problem you are experiencing. Dirty oil might have been the cause but changing the oil won"t clean any crud of the control valve.
If you are new to these tractors, I would strongy advise you to get a Ferguson Shop Manual(~$20), a TE-20 Owners Manual and and the TE-20 parts manual.( You can find these on ebay and on they are available from the parts people on this site.) Together these manuals will provide systems descriptions and exploded views of the components of the various systems so you can understand how things work and how things go together. |
I did exactly as you indicated. With the lift fully raised and the inspection cover open, I moved the control lever down. Nothing happened. I then used a screwdriver to manually push the control fork toward the back of the tractor, again no movement. I drained the oil thinking crud may have been the root of the problem knowing if crud is in the control valve assembly itself it will not correct it. Not knowing how the previous owner cared for or maintained this tractor I figured it can't hurt.
I find it strange that I did not have a oil leak prior to changing the oil a second time, in my case it appears to be a pressurized stream, emitting from the gasketed area just above the "test port". When this pressure "leaks off", the lift then drops. I have not tried, nor will I without knowing just how much pressure is behind these test ports, to see if they will cause the lift to drop. Seems to me I may have a high accumulation of pressure built up in the hydraulic resevoir, this may be normal...just an observation.
When I drained everything out, I was able to observe the control valve moving nicely and smoothly in and out with the control arm actuating its movement. I even observed some residual oil coming out from around the control valve while moving it.
I will aquire the parts and user manual for this tractor, thank you for the suggestions and links. I want to explore all my options before I start disassembling anything. I believe I have read all of John(UK)'s suggestions and he indicated that there are some observations of the system that should be done before disassembling and removing the pump.
Any other suggestions?
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