0380099 JOHNSON MOTOR COVER, Lower front

Coolant and PCV Valve
Replace Hoses
1. Loosen the radiator cap slowly to relieve any pressure and remove the cap. 2. Drain the coolant from the cooling system to a level below the oil cooler.3. Loosen the hose clamps and remove the oil cooler hoses and discard.4. Loosen the hose clamps and remove the hoses from PCV valves (if equipped) on both sides of the engine.5. Install all new coolant and PCV hoses and tighten clamps.Cooling System
Clean/Flush Coolant
Do not flush the system or change the coolant until you read and understand the material in the Cooling System Specifications section of this publication. This procedure is to be used for normal maintenance of cooling system surfaces to return to "like new" condition.For heavy build-up of scale and deposits, a severe acid-type, commercial cleaner or mechanical cleaning may be required.
Our recommended intervals for performing maintenance on the cooling system are based on experience and gathered data relative to the performance characteristics of this engine and its components. Maintaining the cooling system is important because the cooling system has a direct effect on the operation and service life of the engine.Disregard for, or improper maintenance can result in a variety of problems that could shorten the engine's service life or lead to poor engine performance.When you drain, clean/flush the system and replace the coolant, small particles, undesirable chemicals, scale and other deposit formations are removed. These deposits reduce the necessary heat transfer characteristics of the cooling system.If you do not clean/flush the cooling system and replace the coolant as recommended, efficiency of the cooling system will be reduced and, in some cases, result in an increase in fuel consumption.Total neglect for proper maintenance of the cooling system can eventually cause engine overheating problems that could result in severe damage to the engine and its components.By performing regular maintenance on the cooling system, the additional cost of unnecessary repairs may be avoided.
Typical Example1. Remove the radiator filler cap slowly to relieve pressure.2. Remove the cooling system drain plugs or open the drain valve and allow the coolant to drain. Open the cab heater valve to flush coolant from the cab heater.3. Clean and install all drain plugs and/or close drain valve.4. Refill the cooling system with clean water mixed with a 6 to 10 percent concentration of Caterpillar Cooling System Cleaner. Install radiator filler cap.Caterpillar Cooling System Cleaner is available through your Caterpillar dealer. A 9-12 gallon (33-47 L) cooling system capacity requires one gallon (3.8 L) of Caterpillar Cooling System Cleaner to accommodate the 6-10 percent concentration.5. Start and run the engine to circulate fluid in the cooling system for 1 1/2 hours.6. Stop the engine, remove radiator filler cap and cooling system drain plugs.7. Drain the cleaning solution. Flush the cooling system with clean water until draining water is clear. Clean and install all drain plugs and/or close the drain valve.8. Mix a solution of acceptable water and Caterpillar Antifreeze (which contains supplemental coolant additive).When NOT using Caterpillar Antifreeze, add 1 U.S. quart (1 L) of Caterpillar Supplemental Coolant Additive for every 8 U.S. gal (30 L) of cooling system capacity OR change maintenance element only (if equipped). Caterpillar Supplemental Coolant Additive or a coolant additive element (if equipped) should only be used when NOT using Caterpillar Antifreeze.Refer to the topic Cooling System Specifications in this publication for all information regarding acceptable water, antifreeze and supplemental coolant additive requirements.9. Fill the cooling system with the coolant solution at 5 U.S. gal (20 L) per minute or less to avoid air locks.See Refill Capacities chart in this publication for the capacity of your engine's system.10. Start and run the engine with the filler cap removed. Allow the coolant to warm, the thermostat to open and the coolant level to stabilize.
To prevent engine damage, never add coolant to an overheated engine. Allow the engine to cool first.
11. Add coolant mixture if necessary to bring the coolant to within 1/2 inch (13 mm) below the bottom of the fill tube or the correct level on the sight glass, if equipped.
In cold weather, frequently check the specific gravity of the coolant solution to ensure adequate protection. If the engine is to be stored in, or shipped to an area with freezing temperatures, the cooling system must be either protected to the lowest expected outside temperature or drained completely to prevent damage.Always check your cooling system before operating your engine.Since Caterpillar engines incorporate a shunt design cooling system, it is mandatory to always operate the engine with thermostats. Depending on load, failure to operate with thermostats could result in either an overheating or an overcooling condition.
12. Check for coolant leaks at the oil cooler connections.
Typical Example13. Check the condition of the filler cap gasket. If the gasket is damaged, discard the old filler cap and install a new filler cap.14. If the gasket is not damaged, use a 9S8140 Service Tool to pressure test the filler cap. This tool is available from your Caterpillar dealer.The correct filler cap pressure is stamped on the face of the filler cap. If the filler cap does not hold the correct pressure, install a new filler cap.15. Stop the engine.Fuel Injection Nozzles
Exchange/Replace
Whenever the engine performs in such a manner that a fuel injection nozzle is suspected of causing irregular running, smoking or knocking, isolate each fuel injection nozzle, one at a time, to determine the malfunctioning nozzle.1. Start the engine.
Do not loosen nuts at the top of fuel nozzles. The nozzles will be damaged if the top of the nozzle turns in the body when the fuel lines are loosened. The engine will be damaged if a defective fuel injection nozzle is used because of the shape of fuel (spray pattern) that comes out of the nozzles will be incorrect.
2. Loosen the fuel injection line nut at the cylinder head, one at a time, with the engine running. Be sure to tighten each fuel line nut after the test, before the next fuel line nut is loosened.3. When a cylinder is