16753-ZY3-000 Honda STAY, FUEL PIPE A (Honda Code 6990220).

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.
When any servicing or repair of the engine cooling system is performed, the procedure must be performed with the engine on level ground. Level ground will allow you to check accurately the coolant level. This procedure will also help in avoiding the risk of introducing an air lock into the coolant system.
Note: Inspect the water pump and the water temperature regulator after the cooling system has been drained. This inspection 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.Note: Refer to Operation and Maintenance Manual, "General Hazard Information" for information on containing a fluid spillage.
Illustration 1 g03075756
Illustration 2 g02350785
Remove connection hose (1) on the engine. Also remove the drain plug (2). Open the drain cock or remove the drain plug on the radiator.Allow the coolant to drain into a suitable container.
Properly dispose of the drained material. Obey local regulations for the disposal of the material.
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.
Alternative Drain Plug
The cylinder coolant can be drained from the plug below the oil cooler. Refer to illustration 3. If the alternative drain plug (3) is removed, the O ring seal must be replaced. Tighten the drain plug to a torque of 35 N m (310 lb in).
Illustration 3 g03081697Flush
Flush the cooling system with clean water to remove any debris.
Install connection hose. Clean the drain plugs. Install the drain plugs and tighten securely.
Do not fill the cooling system faster than 5 L (1.3 US gal) per minute to avoid air locks.Cooling system air locks may result in engine damage.
Fill the cooling system with a mixture of clean water and Caterpillar Fast Acting Cooling System Cleaner. Add 0.5 L (1 pt) of cleaner per 15 L (4 US gal) of the cooling system capacity. Install the cooling system filler cap.
Start and run the engine at low idle for a minimum of 30 minutes. The coolant temperature should be at least 85° C (185° 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. Remove the connection hose or remove the cooling system drain plugs. Allow the water to drain. Flush the cooling system with clean water. Install the connection hose.
The drain plug O rings on the engine block must be replaced. Clean the drain plugs and install new O ring seal. Install the drain plugs and tighten to a torque of 35 N m (310 lb in).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.
Install the connection hose. Clean the drain plugs. Install the drain plugs and tighten securely.
Do not fill the cooling system faster than 5 L (1.3 US gal) per minute to avoid air locks.Cooling system air locks may result in engine damage.
Fill the cooling system with a mixture of clean water and Caterpillar Fast Acting Cooling System Cleaner. Add 0.5 L (1 pt) of cleaner per 3.8 to 7.6 L (1 to 2 US gal) of the cooling system capacity. Install the cooling system filler cap.
Start and run the engine at low idle for a minimum of 90 minutes. The coolant temperature should be at least 85° C (185° F).