ford diesel blow by

we have this sweet little tc 55 ford new holland diesel bucket loader/hoe tractor with 700 hrs on the clock that was purchased 2nd hand from original owner. we use it around the ford car truck dealership im service mgr. at. the machine has accumulated 200 hrs, now at 700 hrs since we purchased it 3 years ago. yes it gets serviced to death using only ford/new holand filters and ford 10w40 dsl oil. we trenched a footer for one of our buildings. pushed dirt etc this summer. all of a sudden this little 4 cyl is pushing oil fumes out the breather and of course its pushing out fumes at the oil fill if you pull the cap. this is a little turbo engine. engine starts right up ,runs smooth. has full power. coolant not down, oil not down. changed oil and filter on saturday, no residue in oil. no blowing the blues during operation or at start up. no oil in antifreeze. engine not running hot. will probably do a compression check first step........have any of you been around these units and experienced similar issues? and what was the fix.........im guessing a turbo issue......please let me know. thankyou....tp studer (bolivar boy) wooster,ohio.