If for some reason you do not have an operators manual, get one from a dealer or the manufacturer. If the sprinkler system is relatively new, determine what service is required to keep the warranty in effect. Also, determine any other service the manufacturer suggests be performed before the system is put into operation each year. Repair or replace damaged electrical cables and controls, tighten nuts and bolts, inspect welds and stress points for cracks. The sprinkler system should be thoroughly checked for vandalism and any other winter damage.
Many machines require that the grease in all gearboxes be drained and replaced.
If this is not the case, check all gearboxes for moisture accumulation from condensation. Drain off any moisture and check that the proper amount of grease is in each. All fittings should be greased to push out grease that may have hardened during the winter. Check inflation pressure on all tires. Improper inflation can cause tire breakdown, can place stress on the drive system and aggravate wheel track problems on some soils.