2019 Malibu Boats, LLC Owner’s Manual • Page 107attempt to inspect or repair components of the coolingsystem. Most are inaccessible. All can be inadvertentlydamaged if not properly accessed, often necessitatingspecialized tools. Attempting unauthorized inspection orrepair can void the warranty.Coolant RequirementsIn the closed cooling system, verify that there is sufficient coolant/water in the system. (Coolant and water may be required to be mixed,depending on the brand of coolant, most likely in a 50/50 mix.) Becausea closed cooling system retains and recirculates coolant an additionalstep prior to every outing is necessary: Before starting the engine, whileit is still cool to the touch and does not burn skin, check the coolantreservoir level. The instructions for this critical step are explained in theCare and Maintenance section of this Owner’s Manual.Use only a mix of 50/50marine-grade propyleneglycol antifreeze and distilledwater in a Malibu engine closed cooling system. (Premixedcoolant is commercially available, but when manuallymixing use only marine-grade propylene glycol antifreezemixed with 50 percent distilled water.) The use of anyother type of coolant and/or water can void the warranty.NEVER use ethylene glycolor Dex-Cool antifreezecoolant. These types ofcoolants are not formulated for the requirements of theMalibu Monsoon engine. NEVER mix the approvedpropylene glycol coolant with any other type of coolant,including ethylene glycol or Dex-Cool, even in smallamounts. In fact, these different formulations do NOT mixand will not provide the required cooling protection forthe Malibu Monsoon engine.Malibu recommends using Sierra Brand, 5-Year, 100,000-mileMarine Grade Coolant in a 50/50 mix with distilled water to keep thewarranty in effect. Sierra is an environmentally friendly coolant.While some evaporation occurs naturally, it should not occur atan accelerated rate. If a closed cooling tank has significantly lostcoolant, especially if it is nearly empty, a potentially serious issueexists. Present the boat to an authorized Malibu dealer for analysisand correction, prior to starting the engine.Coolant should be flushedfrom the system and fullyreplaced every two years, andthe cooling system carefullychecked for any leaks.The Exhaust SystemAlways operate the blower for several minutes (at least four[4] minutes) prior to startingthe engine, running at a lowspeed or at idle. (Malibuboats are equipped with anautomatic shut-off when the automatic blower system hasoperated prior to starting the engine.) This must be donewith the engine compartment open. Failure to performthis necessary function could result in an explosion of theaccumulated fumes within the compartment, resulting inserious injury or death.https://www.boat-manuals.com/
