If you have an 8N, it has position control. It's the little lever under the seat. Put it in the up position. That controls the position of the lift arms.....if it's working. If not, post back. If the arms drop w/ the tractor off or the clutch depressed, chances are you have a worn lift cylinder or piston (or both) or a leaky pressure relief valve. Take the inspection plate w/ the dipstick off. Lift a heavy implement & look inside w/ the tractor running & the PTO engaged to see if you notice oil running from the top cover. If oil is running steadily from the top cover the lift cylinder needs to be rebuilt. If no oil is running down from the top cover, look at the rear of the pump in the oil with the load still on it and see if you notice turbulence in the bottom. (Some movement of oil will be normal with the PTO shaft turning). You could have a weak pressure relief valve which will be detected by turbulence in the oil. If you see turbulence behind the pump, raise the implement as much as possible, TURN THE ENGINE OFF then reach in and feel the end of the pressure relief valve. If it is leaking you will feel the pressure push your finger off of the end. All pressure relief valves that fail the finger test are bad & should be replaced. But, not all pressure relief valves that pass the finger test are good because some can have slow leaks. So, if all else fails to fix the problem, replace the pressure relief valve. For info on changing the hydraulic fluid, check out tips 3 & 4 below. There are two ways to clean the pump; the quick way that gets most of the crud out of it, & the right way that gets all of it. For the quick clean, after you get the old fluid drained out (overnight is best) remove both inspection plates & start pulling the sludge in the pump base out by hand. Then, get a couple of gallons of kerosene or diesel fuel & pour it into the pump base. Catch it in a bucket & reuse it. (Some folks use a hand garden sprayer.) Flush the pump base out 5 or 6 times. Do not start the engine to run the kerosene through the pump; kerosene and diesel fuel do not have any lubrication properties & you will damage your pump. Some folks will tell you that this 'quick-clean' is not as effective as dropping the pump & doing a full job. I do not dispute that, but it worked for me for 3 years on my 1951 N. If you have the time, drop the pump; that is the right way to do it. Do not attempt to do this w/o the I&T FO4 manual; the pump has a bunch of little parts that will go back together wrong if you do not have the manual to go by. With all of the fluid drained out, block the front wheels & get the rear wheels up at least a foot. (you'll see why soon enough) Remove the 4 bolts holding the PTO shaft in & pull it to the rear & out of the tractor. Put a block under the pump & a jack or more blocks to hold it in place, then loosen all of the bolts. Remove all but the 4 corner bolts. Then, carefully remove them. If you are lucky, the pump will now rest on the block. If not, wrestle it free. The pump has 'ears' that fit into the housing; wiggle it a bit & it will drop free. If you have the rear tires a foot or more off of the ground, you will have enough arm room to hold the pump & lower it at the same time. Once you get it out & on the bench, it comes apart easily & can be cleaned piece by piece. Putting it back is harder than pulling it out because you have a gasket to worry about. (no sealer on the gasket) And, you will need a helper to guide the control rod into the pump rocker shaft.
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