PERIODIC MAINTENANCEJH Series Operation Manual 5712/05PRECAUTIONSThe Importance of PeriodicMaintenanceEngine deterioration and wear occur inproportion to the length of time the enginehas been in service and the conditions theengine is subjected to during operation.Periodic maintenance preventsunexpected downtime, reduces thenumber of accidents due to poor machineperformance and helps extend the life ofthe engine.Performing PeriodicMaintenanceWARNINGExhaust Hazard.Never block windows, vents, or othermeans of ventilation if the engine isoperating in an enclosed area. Allinternal combustion engines createcarbon monoxide gas during operation.Accumulation of this gas within anenclosure could cause illness or evendeath. Make sure that all connectionsare tightened to specifications afterrepair is made to the exhaust system.Failure to comply could result in deathor serious injury.The Importance of Daily ChecksThe Periodic Maintenance Scheduleassumes that the daily checks areperformed on a regular basis. Make it ahabit to perform daily checks before thestart of each operating day. See DailyChecks on page 62.Keep a Log of Engine Hours andDaily ChecksKeep a log of the number of hours theengine is run each day and a log of thedaily checks performed. Also note thedate, type of repair (e.g., replacedalternator) and parts used for any serviceneeded between the periodic maintenanceintervals. Periodic maintenance intervalsare every 50, 250, 500 and 1000 enginehours. Failure to perform periodicmaintenance will shorten the life of theengine.NOTICEFailure to perform periodic maintenancewill shorten the life of the engine and mayvoid the warranty.Yanmar Replacement PartsYanmar recommends that you usegenuine Yanmar parts when replacementparts are needed. Genuine replacementparts help ensure long engine life.Tools RequiredBefore you start any periodic maintenanceprocedure, make sure you have the toolsyou need to perform all of the requiredtasks.Ask Your Authorized YanmarMarine Dealer or Distributor forHelpOur professional service technicians havethe expertise and skills to help you withany maintenance or service relatedprocedures you need help with.