Yanmar diesel using oil

[jjohn]

I have a 24hp Yanmar 360 hrs used 200ml oil in 5hrs of operation.
50 hrs ago had the rear main seal replaced, leaking.
Since then it is using the oil not leaking.
There is oil blowing out the dipstick which points me to crank case pressure, and pcv valve not working properly.
The pcv in this model has a diaphragm and spring mechanism in the valve cover which opens to let pressure out into the inlet manifold.
The last 5 hrs use it didn't use any oil. Which tells me its not rings.
I've taken it to the John Deere dealer only to be told yep there's no oil leak and they didn't inspect the valve. Wtf?
"Oh we didn't have a gasket"
"We don't know"

Any clues for me plz?
I'll be checking the valve myself as soon as I get time.

 

[Old.Tony]

I'd take the valve off the PCV, connect the PCV directly to a catch can and see what it catches. Oil blowing out the dipstick isn't good - I know my generator's dipstick screws in with a seal to ensure that oil can't blow out there, which means the valving at the PCV will work as intended. Does your dipstick screw in, and is its seal intact?