Twin Disc Transmission
 

I have twin Disc Transmissions on my Cat.I changed the oil and cleaned the screen.The problem is on one of the transmissions the oil is not registering on the dipstick.It is right up to the vent hole,which you unscrew to fill it.It says to check the level while running in neutral but I do not want to start it until I get a reading.Will it circulate as soon as the pump is turning?.The other one registers fine.
Mark