Here is one for you.... Amy and I took the loader off the new to me OS9 yesterday. Took 3 hours. Loader came off just fine, dropped the struts, pulled the pins and lifted it right off the mounting bosses then the issues begain. Shut off the tractor relieved the pressure in all functions and then tried to pull the Parker quick disconnects from the loader control. No way. They were all frozen. I suspect the previous owner never removed the loader which is why the original fuel filter was still on the motor and the separator was untouched as well (you cannot access the fuel filter or separator without removing the loader on an M9 because space is very limited (more on that later).
Anyway, with Amy holding a 27MM wrench on the top of the Parkers, I proceeded to spray them with PBlaster and slowly work the collars to get them free. The Parker's were loaded with grit and dirt and repeated flushing with PB and light machine oil and each one finally released. Took 3 hours total.
So I get the loader off and take the fuel filter off to replace it. Keep in mind that this unit has 3500 hours on the hour meter. Original filter. I took it off and cut it apart and it was loaded with crud. Pulled the separator and I think the previous owner tried to clean it one time (and failed because the element that should have been on the boss was cocked in the housing and crushed). Only thing filtering the fuel was the primary filter, the separator was non functional so a quick trip to the dealer and 30 bucks later I have a new element. I might add the clear bowl in the bottom was loaded with crud, had to clean it with a toothbrush and brake cleaner to get the crud out. Clean and functional now. I'm surprised the engine even ran. Purrs like a kitten now.
If you never remove the loader on an M9, you cannot change the fuel filter or really get to the separator either. All is good now. Waiting for the outboard seal to come in so I can install it in the center housing, the right outboard planetary is leaking. Least he changed the oil and greased it. I'll give him that. Never changed the air filter either. When I pulled the secondary air filter, it was packed with dirt. Changed both the primary and secondary filters.
Now I need to degrease the loader. It has years of accumulated grease on it. The previous owner kept the unit greased but never washed it. That won't happen here.