JD 401-BD serial no. 308556T. Need to put a remote hydraulic control on for a sickle mower. The tractor has a loader with a two spool valve, but we don't want to take the loader control off the loader. I'm assuming the tractor hydraulics are closed center, so I'm guessing we need a special spool valve? The connections are under the right side kick plate, one line is teed into a line that goes to the steering, and other looks like it just dumps into the filter cover.
Don't know much about the exact tractor, other than i think it's related to the 4010. When my dad had a 4020 with a loader he added a power beyond valve bank to run a bat wing and hydro swing. Probably gonna be the easiest/cheapest solution.
We found a single spool valve from the local odds&ends guy here in town. Plumbed it up, and the bar would lift, but would not go down unless you stood on it, or shut the tractor off. We figured that there was too much pressure in the return side, so we plumbed a hose up to the other end of the lift cylinder. Mowers are normally single-acting, but we wanted to see if it would work. It did, but with it plumbed double-acting, the cutter bar will not float, and our valve doesn't have the float function. I guess I'll have to call Force America on Monday and see about a closed-center spool valve. My guess is the right valve will not have a built-in relief and the return will be a free-flow back to tank.
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I found a spec sheet. Lists a closed center system. So you should be able to T off the pressure line between the pump out let and your current valve's inlet, into the inlet of your new valve. I would plumb the return side of the valve to the tank if at all possible. I would not be worried about using the 2nd working port of the valve as long as the valve is not off the wall?
Tractor does not currently have any valve on it other than the internal 3-pt hitch control. The loader has a valve (if that's what your referring to as my current valve) and the supply port on the tractor for that valve is where we plumbed into. Am I on the right train of thought that the closed-center system high pressure standby is blasting through the relief valve in current spool that we installed and creating pressure on the return side? My other question, since I'm not familiar with standalone spool valves, is will the "correct" spool valve basically just be a casting with a spool and 4 ports? If the valve on the loader wouldn't be mounted upside down, under a plate, completely covered in dirt and grime, we could inspect that more closely. In case anyone is wondering why I'm messing around with this tractor, it belongs to the city where I live. The public works director has been insisting he needs a new $40,000 tractor to mow ditches and whatnot. He convinced the council to purchase a new 3-point sickle mower, and since I'm on the city council, myself and one other guy are trying to get this tractor and mower operational. We knew going in that the tractor didn't have remote hydraulic capabilities other than the loader, but didn't think finding a valve would be an issue.
It wasn't uncommon to have a sickle mower on the side of an industrial tractor. A JD dealer or the maker of the mower may know what valve you need.