Hi Jon - Nice description - we're on the same wave-length. I'm guessing that 3) is located up on the loader frame.(Two of ours have this configuration.) The pressurized fluid (diverted by 2) goes to 3, and in neutral returns to the transmisson. Some pressure is getting by the internal workings of yours, into the ports for the lift cyl. 3) is normally a 2 spool 4-way off-the-shelf valve unless you have some bells and whistles like self-levelling or float, or some specialized mounting. I haven't found either feature particularly useful. If your hoses are all separate (none going into the loader frame with gaskets or o-rings) you should be able to exchange it with any suitable replacement unit. You certainly won't destroy the beast! One of our valves is a Gresen SP4-4, 2 spool double acting (or 4-way), the other is a european 2 spool 4-way rated at 6 gpm, 2500 psi. (It was cheaper.) Cross is another common (and good) valve name. The MF internal system puts out 4 gpm max. and the 35's have a 2250 psi internal relief valve. The 4-way permits cyl operation both ways under pressure. In loaders, this means down pressure on the loader lift cyls. Some have only lift, with gravity lowering. You can get the proper valve combination for these (1 double acting and one single acting spool) but the standard one is cheaper; you plumb the unused port to the return line. The only other snag you might encounter is the hose connections to the valve. The two common ones are pipe thread and o-ring boss (JIC?). The Gresen (and Cross) valves are normally pipe threads. Adaptors are readily available at the valve suppliers if your hoses are not pipe thread. Might be a good time to take a good look at the hoses and fittings too - for safety. Checked or frayed hoses should be replaced. And a lot of loaders have been plumbed up with galvanized or black iron pipe fittings. These fittings are rated at 300 psi max operating pressure. While they're OK in the return circuit, the pressurized system can run close to 2500 psi. Hydraulic fittings are rated for these pressures, and are not that much more expensive. Hope this helps.
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