Dear brily farms and ruffdog:
You will notice the Service Bulletin does NOT mention model TC33D as being involved in the application. The oil fill dilemma began as a result of emissions system "improvements" begun on the DA models around 2005.
I'm sorry the bulletin does mention the CIH...
I vote for a slipping drive belt. Either the belt is shot, or the tensioner is weak, or both. Get a can of Belt Grip and apply liberally. Go mow and see if there is a difference. The pitch (whine) of the deck at 540 should remain the same at no load and under load.
My prejudice is seeping out. I suggest you consider a New Holland TZ 18 thru TZ 25 series with loader and mid-mount mower. They feature a left hand lever that controls the mower height and locks it in the raised position, which is high enough for most dirt work. Mower removal is simple with...
Make the radiator shop your first stop. It may be a simple, inexpensive fix for them. I had the radiator off a tz18 to replace the thermostat. Radiator removal and replace was the easy part.
Near each set of wheels is a flexible joint and each joint has two micro switches which activate power to the wheels. When that set of wheels falls behind, one switch will power the wheels until they catch up to the line. The speed of the system is controlled by a per cent age dial that controls...
No offense, but your dreaming. Minimum of 100 hp to pick it up and preferably 150 hp to spin it in tough conditions. Even a 5 rotor disc will overwhelm your bota. You might consider a 5' 2 rotor drum mower, or a 7' New Holland haybine.
Flush, flush, and flush that housing to remove all that crap. Perhaps someone has a tried and true method to suggest for cleaning the housing and bearings.