87532-ZW9-640 Honda MARK, THROTTLE (ENGLISH) (Honda Code 6643696).

Use of commercially available cooling system cleaners may cause damage to cooling system components. Use only cooling system cleaners that are approved for Caterpillar engines.
Note: Inspect the water pump and the water temperature regulator after the cooling system has been drained. This service is a good opportunity to replace the water pump, the water temperature regulator, and the hoses, if necessary.Drain
Pressurized System: Hot coolant can cause serious burns. To open the cooling system filler cap, stop the engine and wait until the cooling system components are cool. Loosen the cooling system pressure cap slowly in order to relieve the pressure.
Stop the engine and allow the engine to cool. Loosen the cooling system filler cap slowly to relieve any pressure. Remove the cooling system filler cap.
Illustration 1 g06011336
Typical C12.9 Marine Engine coolant drain locations
(1) Under low-pressure aftercooler
(2) Front of engine on crossover pipe
(3) Right side of engine under heat exchanger
Attach a drain hose to the drain valves.
Loosen and remove drain plugs. Allow to drain in to a suitable container.
Dispose of used engine coolant properly or recycle. Various methods have been proposed to reclaim used coolant for reuse in engine cooling systems. The full distillation procedure is the only method acceptable by Caterpillar to reclaim the used coolant.
Care must be taken to ensure that fluids are contained during performance of inspection, maintenance, testing, adjusting, and repair of the product. Be prepared to collect the fluid with suitable containers before opening any compartment or disassembling any component containing fluids.Refer to Special Publication, NENG2500, "Cat Dealer Service Tool Catalog" or refer to Special Publication, PECJ0003, "Cat Shop Supplies and Tools Catalog" for tools and supplies suitable to collect and contain fluids on Cat products.Dispose of all fluids according to local regulations and mandates.
Flush
Flush the cooling system with clean water to remove any debris.
Close the drain valves. Refer to the Specifications Manual for your particular engine for more specific information on the proper torques. Refer to the Specifications, SENR3130, "Torque Specifications" for more general information on the proper torques.
Fill the cooling system no faster than 19 L (5 US gal) per minute to avoid air locks.
Fill the cooling system with a mixture of clean water and Cat Fast Acting Cooling System Cleaner. Add .5 L (1 pt) of cleaner per 15 L (4 US gal) of the cooling system capacity. Install the cooling system filler cap.
Start the engine and run the engine at low idle for a minimum of 30 minutes. The coolant temperature should be at least 82 °C (180 °F).
Improper or incomplete rinsing of the cooling system can result in damage to copper and other metal components.To avoid damage to the cooling system, make sure to completely flush the cooling system with clear water. Continue to flush the system until all signs of the cleaning agent are gone.
Stop the engine and allow the engine to cool. Loosen the cooling system filler cap slowly to relieve any pressure. Remove the cooling system filler cap. Drain the cooling system. Refer to this Operation and Maintenance Manual, "Coolant - Change" section.
Flush the cooling system with clean water. Close the drain valves. Refer to the Specifications Manual for your particular engine for more specific information on the proper torques. Refer to the Specifications, SENR3130, "Torque Specifications" for more general information on the proper torques.Cooling Systems with Heavy Deposits or Plugging
Note: For the following procedure to be effective, there must be some active flow through the cooling system components.
Flush the cooling system with clean water to remove any debris.
Close the drain valves. Refer to the Specifications Manual for your particular engine for more specific information on the proper torques. Refer to the Specifications, SENR3130, "Torque Specifications" for more general information on the proper torques.
Fill the cooling system no faster than 19 L (5 US gal) per minute to avoid air locks.
Fill the cooling system with a mixture of clean water and Cat Fast Acting Cooling System Cleaner. Add .5 L (1 pt) of cleaner per 3.8 L to 7.6 L (1 to 2 US gal) of the cooling system capacity. Install the cooling system filler cap.
Start the engine and run the engine at low idle for a minimum of 90 minutes. The coolant temperature should be at least 82 °C (180 °F).
Improper or incomplete rinsing of the cooling system can result in damage to copper and other metal components.To avoid damage to the cooling system, make sure to completely flush the cooling system with clear water. Continue to flush the system until all signs of the cleaning agent are gone.
Stop the engine and allow the engine to cool. Loosen the cooling system filler cap slowly to relieve any pressure. Remove the cooling system filler cap. Drain the cooling system. Refer to this Operation and Maintenance Manual, "Coolant - Change" section.
Flush the cooling system with clean water. Close the drain valves (1). Refer to the Specifications Manual for your particular engine for more specific information on the proper torques. Refer to the Specifications, SENR3130, "Torque Specifications" for more general information on the proper torques.Fill