Draining And Refilling Cooling System - Isuzu 4JA1 Workshop Manual

6B – 8 ENGINE COOLING

Draining and Refilling Cooling System

Before draining the cooling system, inspect the system and
perform any necessary service to ensure that it is clean, does
not leak and is in proper working order.
(EC) level should be between the "MIN" and "MAX" lines of
reserve tank when the engine is cold. If low, check for leakage
and add EC up to the "MAX" line.
There should not be any excessive deposit of rust or scales
around the radiator cap or radiator filler hole, and the EC
should also be free from oil.
Replace the EC if excessively dirty.
1. Completely drain the cooling system by opening the drain
plug at the bottom of the radiator.
P1010064
2. Remove the radiator cap.
WARNING: To avoid the danger of being burned, do not
remove the cap while the engine and radiator are still hot.
Scalding fluid and steam can be blown out under
pressure.
3. Disconnect all hoses from the EC reserve tank.
Scrub and clean the inside of the reserve tank with soap
and water. Flush it well with clean water, then drain it.
Install the reserve tank and hoses.
4. Refill the cooling system with the EC using a solution that is
at least 50 percent antifreeze.
Procedure for filling with coolant (in case of full change)
• Make sure that the engine is cool.
• Open radiator cap pour coolant up to filler neck.
• Pour coolant into reservoir tank up to "MAX" line.
• Tighten radiator cap and start the engine. After idling for 2
to 3 minutes, stop the engine and reopen radiator cap. If the
water level is lower, replenish.
WARNING: When the coolant is heated to a high
temperature, be sure not to loosen or remove the radiator
cap. Otherwise you might get scalded by not vapor or
boiling water. To open the radiator cap, put a piece of
thick cloth on the cap and loosen the cap slowly to reduce
the pressure when the coolant has become cooler.
The engine coolant