In Reply to: 9N-Hydrulics/PTO fluid posted by Jim Thorn on June 10, 2018 at 11:04:44:
Yes, you are correct, sir. ALL 9Ns and 2Ns have a 3-speed transmission and NO POSITION CONTROL for the hydraulics. There are three drain ports on the underside of tractor -always start with small square head NPT plug on the diffy case. Move forward as you drain each port. Be aware that a fourth drain is the engine oil drain port on the bottom of the engine oil pan -do not remove it. See this document from HOW-TO's for reference only. Page 9 has the drain procedure. Be aware that the 9N/2N hydraulic systems had differences. The filler port is on top of the shifter cover. Capacity is 5 gallons, but do not ever put that much in at one time. Start with 3 or 4 gallons.
Fill with GL-1 SAE 90 Gear Oil: