While I'm rebuilding this I am going to convert it from power assist to full hydraulic steering. The power assist valve is 4 port and the new steering valve is a JD 5 port valve...
What throws a kink in my plumbing is that the 400's hydraulics are Pump --> Valves --> Steering assist valve --> Cooler --> Reservoir.
So with a 5 port I will need to change... anyone have any input on this?
I've read your write up with interest. I have a JD 420 that I will eventually repower--probably with a diesel.
As for a thermostat for your electric fan. Auto Zone (Advanced Auto Parts I believe in your neck of the woods) used to sell a thermostatic control for electric fans. It had two switches--1 for regular fan, and one for the A/c, the relays for the fan, and a temperature probe which actually slid between the fins of the radiator and was clipped on the other side. I installed one on my 97 Toyota Camry--the PO had front ended it, and installed an aftermarket radiator and front clip, and didn't bother to hook up the temp sensors--he just had the fans wired to run all the time... After I installed the system, the fans came on as needed (some adjustment is provided in the system), and I never had any more problems with it. FWIW.
However, I also have the steering valve and cylinder off a JD 400 that I wanted to install on my Bolens HT23, but I'm unfamiliar with how to set up the valve. I know the valve was on the LH side and the cylinder on the RH side on the JD400... it will be opposite that for the Bolens because the Pitman Arm is on the RH side. But, my big question, since the valve only has a small amount of movement, when it's installed on the machine, how do you adjust it? I can see that pressure against it from the drag link to turn the wheels right would press it in and actuate the cylinder but how does it sense when you're turning left, etc.
Any input from anyone would be appreciated.