0309577 EVINRUDE LOCKPLATE,Rod screw

Water
Never use water alone without Supplemental Coolant Additives (SCA) or without inhibited coolant. Water alone is corrosive at engine operating temperatures. Water alone does not provide adequate freeze or boil protection.
Distilled or deionized water is recommended for use in engine cooling systems. DO NOT use hard tap water or salt softened tap water in engine cooling systems. If distilled or deionized water is not available, use water that meets the minimum acceptable requirements listed in the following chart. Additives
Additives must be added to all coolant mixtures. Additives help prevent the formation of rust, scale, and mineral deposits. Additives protect metals from corrosion, prevent liner cavitation, and contain antifoaming agents. Additives deplete during engine operation and need to be replenished. This can be done by treating conventional coolants with Supplemental Coolant Additives (SCA) or by treating Extended Life Coolant (ELC) with Extender.Additives must be added at the proper concentration. Overconcentration of additives can cause the inhibitors to drop out of the solution and form a gel in the radiator. An overconcentration of additives produces excessive deposits on water pump seals that can cause the water pump seal to leak. Underconcentration of additives can produce pitting, cavitation, erosion, rust, scale, and foaming.Glycol
Glycol in the coolant provides boil and freeze protection, prevents water pump cavitation, and reduces cylinder liner pitting. For optimum performance, Caterpillar recommends a 50/50 glycol/water coolant mixture. All Caterpillar engines equipped with air-to-air aftercooling (ATAAC) require a MINIMUM of 30 percent glycol to prevent water pump cavitation.Ethylene glycol is used in most conventional heavy duty (HD) coolant/antifreezes. However, propylene glycol may also be used. Both ethylene glycol and propylene glycol have similar fluid properties in a 50/50 glycol/water mixture. Both ethylene glycol and propylene glycol provide similar heat transfer, freeze protection, corrosion control, and seal compatibility. The following charts define the temperature protection provided by the two types of glycol.
Do not use propylene glycol in concentrations that exceed 50 percent glycol because of propylene glycol's reduced heat transfer capability. Use ethylene glycol in conditions that require additional boil or freeze protection.
Caterpillar recommends the use of a refractometer for checking the glycol concentration. Use the 1U-7298 Coolant Tester (°C) or use the 1U-7297 Coolant Tester (°F). The testers give immediate, accurate readings and can be used with ethylene or propylene glycol.Coolant Recommendations
DO NOT use a commercial coolant/antifreeze that ONLY meets the ASTM D3306 or D4656 specification. This type of coolant/antifreeze is made for light duty automotive applications.
There are two primary coolant types used in Caterpillar on-highway diesel engines:* Preferred - Caterpillar Extended Life Coolant (ELC), or... a commercial ELC meeting the Caterpillar EC-1 specification* Acceptable - Caterpillar Diesel Engine Antifreeze/Coolant (DEAC), or... a commercial heavy duty (HD) coolant/antifreeze meeting the TMC RP329 specification, or ...a commercial HD coolant/antifreeze meeting the ASTM D5345 or D4985 specificationCaterpillar ELC will provide the best coolant service life, corrosion protection, water pump seal service life, and radiator service life.Caterpillar recommends a 50/50 glycol/water mixture for optimum coolant/antifreeze performance. Caterpillar DEAC and commercial heavy duty (HD) coolant/antifreezes meeting the TMC RP329 specification do not require SCA treatment at initial fill. Commercial HD coolant/antifreezes meeting the ASTM D5345 or D4985 specification DO REQUIRE SCA treatment at initial fill. Extended Life Coolant (ELC)
Caterpillar provides Extended Life Coolant (ELC) for use in heavy duty diesel engines, natural gas engines, and automotive engines. The Caterpillar ELC anticorrosion package is totally different from conventional coolants. Caterpillar ELC is an ethylene glycol based coolant which contains organic acid corrosion inhibitors and antifoaming agents. Caterpillar ELC has fewer nitrites than other coolants. Caterpillar ELC has been formulated with the correct levels of additives to provide superior corrosion protection for all metals in diesel engine cooling systems.Caterpillar ELC extends coolant service life to 966 000 km (600,000 mi) or Six Years. Caterpillar ELC does not require frequent additions of SCA. A "one time only" coolant Extender is the only maintenance addition required. The Extender should be added to the cooling system at 483 000 km (300,000 mi), or one half of the ELC service life.Caterpillar ELC is available Premixed with distilled water in a 50/50concentration. The Premixed ELC provides freeze protection to -36°C (-33°F). The Premixed ELC is recommended for initial fill and for topping off the cooling system. ELC Concentrate is available to lower the freezing point to -51°C (-60°F) for Arctic conditions. ELC Concentrate should be used to adjust the coolant freeze point as required where Caterpillar ELC Premixed freeze protection is not acceptable.Consult your Caterpillar dealer for part numbers and available container sizes. The Caterpillar EC-1 Specification is an industry standard developed by Caterpillar. The EC-1 specification defines all of the performance requirements that an engine coolant must meet in order to be sold as an extended life coolant for Caterpillar engines. Caterpillar ELC can be used in most OEM diesel, gasoline, and natural gas engines. Caterpillar ELC meets the industry performance requirements of ASTM D4985 and D5345 for heavy duty low silicate coolant/antifreezes. Caterpillar ELC also meets the industry performance requirements of ASTM D3306 and D4656 for automotive applications.ELC Cooling System Maintenance
Caterpillar ELC Extender
Caterpillar ELC Extender is added to the cooling system halfway through the ELC service life. The cooling system should be treated with Extender at 483 000 km (300,000 miles) or one half of the ELC service life. Use the chart below to determine the proper amount of Caterpillar Extender required.Consult your Caterpillar dealer for part numbers and available container sizes. ELC Cooling System Cleaning
CLEAN WATER is the only system cleaning/flushing agent required when ELC is drained from the cooling system.ELC can be recycled. The drained coolant mixture can be & "distilled" to remove the ethylene glycol and water for reuse. Consult your Caterpillar dealer for more information.After draining and refilling the cooling system, operate the engine with the radiator filler cap removed until the coolant reaches normal operating temperature and the coolant level stabilizes. Add ELC mixture as necessary to fill the system to the proper level.Changing to Caterpillar ELC
To switch the cooling system from