Mitsubushi — 6 Check the oil pan and other parts for oil leakage. Repair any oil leakage found.

A Mitsubushi service procedure — check it applies to your exact model before use.

Procedure

7 Crank the engine for about 10 seconds or less using the starters, and wait for about 1 minute.
8 Repeat the above cranking operation several times to circulate oil in the engine. To crank the engine, shut off the fuel supply to the engine (keep the control rack of the fuel injection pump in the OFF position) and operate the starters.
9 Check the oil level with the oi! level gage again, and add oil if necessary. inspection of Engine Oil for Mixing of Fuel and Water Sample 1 to 2 L [0.26 to 0.53 U. S. gal] of engine oil, and check for abnormal odor and.discoloration. to deter- mine the mixing of fuel and water. If fuel is mixed with the engine oil, the oil will smell like fuel. lf water is mixed with the engine oil, the oil will be milky white. If the oil is normal, add engine oil of the same brand in the engine. lf fuel and/or water is mixed with the engine oil, contact a Mitsubishi dealer. Note: Regarding replenishment of engine oil, refer to "Lubricating System” (3-5). if the engine continues to operate with engine oil mixed with fuel or water, the engine oil viscosity creases and this can cause serious accidents such as seizing of bearings. If fuel or water is detected in the engine oil, find the cause of the problem, and repair. If the problem cannot. be corrected easily, contact a Mitsubishi dealer. Chapter 6 PERIODIC INSPECTION AND MAINTENANCE PROCEDURES Cooling System Changing Coolant Remove the radiator cap only after the engine cools to room temperature. Place a cloth over the cap, and turn the cap about a half turn or half a turn upright position Turn cap about Stand the lever to stand the lever to upright position to release internal pressure. Opening the radiator cap while the engine is hot causes steam and hot coolant to blow out, resulting in skin burns. Coolant (containing LLC) drained from an engine is toxic, and must not be disposed of into regular sewage. For disposal of used cool- ant, consult a Mitsubishi dealer. The service life of LLC is 2 years. Be sure to change coolant at least once every 2 years. Draining coolant
1 When draining coolant immediately after engine operation, let the engine idle at low speed for 5 to 6 minutes and lower the coolant temperature to 70 to 80°C [158 to 176°F]. fig.6-15 Draining coolant (Engine main parts)
2 Open the radiator cap.
3 Place coolant receiving cans under the drain > cocks on the engine and water pump, and open SRL, the drain cocks to drain coolant. Cleaning the cooling system Water drain ‘cock
1 Close the drain cocks or plug. fig.6-16 Draining coolant (Water pump)
2 Pour a cleaning solution (non-corrosive solution to rubber and metals) in the cooling system, and operate the engine at 800 to 900 min" for about 15 min- utes, then drain the cleaning soiution. ,
3 Close the drain cocks or plugs. , _ 4 Pour fresh water, and operate the engine at 800 to 900 min" for about 10 minutes. Continue flushing the cooling system in the above manner until the draining water is clear. Chapter 6 PERIODIC INSPECTION AND MAINTENANCE PROCEDURES nee _ Pouring coolant
1 Make sure the drain cocks on the engine and water pumps are closed tightly.
2 Remove the expansion tank cap, and pour undiluted LLC. Note:(a) Determine the amounts of LLC and water to be poured by using the LLC concentration chart. (b) Regarding coolant, refer to "Coolant" (4-6). Coolant capacity (engine only) . Approx. 100 L [26.4 U. S. gal)
3 Pour water (soft water with minimal impurities, such as tap water) slowly to the full level.
4 Check the expansion tank and other parts for coolant leakage. \f coolant leakage is found, repair.

Source: manual:Mitsubishi S12A2-Y1TA2 Manual.pdf. Figures and steps are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.