0323406 JOHNSON VALVE SEAT, Relief valve

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 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.
Illustration 1 g03890108
Typical example
Note: Refer to Operation and Maintenance Manual, "General Hazard Information" for information on Containing Fluid Spillage.
Open the cooling system drain valve (if equipped). If the cooling system is not equipped with a drain valve, remove one of the drain plugs (1).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.
Drain Plugs for Factory Installed Radiators
Illustration 2 g06164641
Typical example
(2) Three cylinder radiator drain plug
(3) Four cylinder turbocharged engine radiator drain plug
(4) Four cylinder turbocharged aftercooled engine drain plug front of radiator
Tighten drain plug (2) to a torque of 4 N m (35.4 lb in)
Tighten drain plug (3) to a torque of 4 N m (35.4 lb in)
Tighten drain plug (4) to a torque of 6 N m (53. lb in)Flush
Flush the cooling system with clean water to remove any debris.
Close the drain valve (if equipped). Clean the drain plugs. Install the drain plugs. Refer to Torque Specifications, SENR3130 for more information on the correct torques.
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 pint) 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 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. Open the drain valve (if equipped) or remove the cooling system drain plugs. Allow the water to drain. Flush the cooling system with clean water. Close the drain valve (if equipped). Clean the drain plugs. Install the drain plugs. Refer to Torque Specifications, SENR3130 for more information on the correct 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 valve (if equipped). Clean the drain plugs. Install the drain plugs. Refer to Torque Specifications, SENR3130 for more information on the correct torques.
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 pint) 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 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. Open the drain valve (if equipped) or remove the cooling system drain plugs. Allow the water to drain. Flush the cooling system with clean water. Close the drain valve (if equipped). Clean the drain plugs. Install the drain plugs. Refer to