GB-37SAFETY, OPERATORS & MAINTENANCE MANUAL11 MAINTENANCE & LUBRICATION11.15 MOWING BLADES• Check the state of the cutter blades at regularintervals.The blades:• Must not show signs of damage such astwisted, bent or deformed parts of blades• Must be properly attached by the flange in themiddle of blades• Must be sharp• The fastening bolts of the flange must not bedamaged• For proper and reliable functioning the blade isstatically and dynamically balanced by themanufacturer. This balance must be preservedduring the entire use of the blade• The blade must be statically balanced aftereach sharpening• To tighten the blade, use a torque wrench anda specified tightening torque of 60 NmIf the blades are damaged, it is prohibited to:• Straighten it• Heat it• Weld it• Ream them or otherwise change theirconstructionWhen replacing worn-out parts followthese rules:• The blade may only be sharpened within thepermitted wear limit. Balancing must becarried out after sharpening.• The blade cannot be repaired.• When changing the blade, use new fasteningbolts if the current ones show signs ofdamage. Only high-tensile M10 bolts may beused for this purpose. No other steel bolts areacceptable.• If the mowing mechanism vibrates whenengaged, do not continue operating themower, turn it off and contact your localdealer.• To tighten bolts use torque listed in the chartat the end of this chapter (see 11.19)Changing the mowing blades• Raise the mowing device to the transportposition• Stop the engine, switch off the remote radiocontroller and push the emergency button onthe body of the mower.• Disconnect the battery.• Lift one side of the mower until it leansagainst the handles on the other side. Alwayslift the mower on the exhaust side tilt itagainst the hydraulic tank side to prevent oilentering the air cleaner.• Secure the lifted side against falling bysupporting it.• Use gloves when changing the blades• Loosen four fastening bolts on the flange ofthe blade. Remove the bolts and the flange• Be careful when removing the last bolt, theblade may fall to the ground• After the blade is replaced, fasten it byworking in the reversed order• Always check the bolts when fastening theblade.• After attaching the blade, check its tightness.Be very careful when engaging the mowingmechanism for the first time after thereplacement. Check for unknown sounds,vibrations etc.NOTICE:Always lift the mower on the exhaust sideand tilt against the hydraulic tank side toprevent oil entering the air cleaner. Beaware of oil spills.