Hello Guys. My name is Rob, and I have been running Exmark Walk-behinds for 12 years now and love them. Just recently upped the acrage and decided to buy a used Exmark Ct 52 lazer z. I am currently winterizing it and doing maintenence on it. Now the hydros are working well but I want to change the filter. I was told to fill the filter up with hydro oil screw it on and jack up the rear end and manually turn the tires forwards and backwards 10-15 times to alleviate air bubbles. Could anyone tell me if this is correct and if it is what else should I be aware of while changing this dellicate system? Thanks guys!