Coolant level check. Cooling system-draining and filling

Coolant level check

The cooling system is closed and designed to maintain coolant level to top of radiator.

WARNING: DO NOT OPEN RADIATOR DRAINCOCK WITH ENGINE RUNNING OR WHILE ENGINE IS HOT AND COOLING SYSTEM IS UNDER PRESSURE.

Remove radiator cap. The coolant level should be to top of radiator. If not, and if coolant level in coolant recovery bottle is at ADD mark, check for:

• An air leak in coolant reserve/overflow tank or its hose
• An air leak in radiator filler neck
• Leak in pressure cap seal to radiator filler neck

Cooling system-draining and filling

WARNING: DO NOT REMOVE CYLINDER BLOCK DRAIN PLUGS OR LOOSEN RADIATOR DRAINCOCK WITH SYSTEM HOT AND UNDER PRESSURE.

SERIOUS BURNS FROM COOLANT CAN OCCUR.

DO NOT WASTE reusable coolant. If solution is clean, drain coolant into a clean container for reuse.

DRAINING

NOTE: On the 4.7L engine the thermostat is an inlet side thermostat. This means that the engine coolant will not drain when the radiator drain petcock is opened. It will be necessary to remove the thermostat housing and thermostat to allow the coolant traped in the engine block to drain.

(1) Remove radiator pressure cap.

(2) Loosen radiator petcock.

(3) Place a drain pan under the thermostat housing, then remove the thermostat housing and thermostat (4.7L only).

(4) Remove cylinder block drain plugs. Refer to (Fig. 26) (Fig. 27).

Fig. 26 Cylinder Block Drain Plug-5.2L/5.9L Engines-Typical

1 - BLOCK DRAIN PLUG

Fig. 27 Cylinder Block Drain Plug-4.7L Engine- Typical

1 - CYLINDER BLOCK DRAIN PLUG

2 - EXHAUST MANIFOLD AND HEAT SHIELD

REFILLING

Clean cooling system prior to refilling. Refer to Cooling System Cleaning section of this group.

(1) Install cylinder block drain plug(s) s. Coat the threads with Mopart Thread Sealant with Teflon.

(2) Close radiator petcock.

(3) Fill cooling system with a 50/50 mixture of water and Mopart Antifreeze/Coolant.

(4) Fill coolant reserve/overflow tank to FULL mark on indicator stick.

(5) Start and operate engine until thermostat opens (upper radiator hose warm to touch).

(6) If necessary, add a 50/50 water and Mopart Antifreeze/Coolant mixture to the coolant reserve/ overflow tank. This is done to maintain coolant level between the FULL and ADD marks. The level in the reserve/overflow tank may drop below the ADD mark after three or four warm-up and cool-down cycles.