98 kw t800 engine runs constantly

So on my Coronado, the fan would stay on, turned out the clutch was stuck from sitting for a few months. My Coronado is default engaged, meaning it takes pressure to disengage. So I unhooked the air line from the solenoid and put shop air pressure to it. Shop air is 150psi. The jolt of the higher pressure, or just being able to give the clutch a quick burst rather than a slow build up, popped the clutch loose and its working great since.
Does your fan spin free at start up with no air?

 

Ok, so yours is default "disengaged".
So you should have a dash switch then to turn it on manually? Check that switch for condition and operation.