I recently purchased a super z diesel at auction with a 72 inch deck and need help troubleshooting a deck issue. The machine is super clean and was used at a university hour meter just shy of 1000 hrs. Looks well maintained and has new looking filters and clean oil/ fluids but when the mower switch is activated the deck turns but does not generate any significant rpm's. I am a newbie to zero turns and need advice on what to check on this hydraulic deck. Is it likely that the Parker motor is faulty or is it more likely a hydraulic pump issue? No abnormal vibration is felt at all. Any input would be appreciated. Thanks, rsliker