1. Make a visual check of the cooling system.
2. Check the ground under the vehicle.

Is there coolant visible on the grorund?

--

Go to Step 3

Go to Step 2

Inspect the cooling system for proper pressure retention.

Does the cooling system maintain the correct pressure?

--

Go to Step 13

Go to Step 3

Check for a leaking radiator.

Does the radiator leak?

--

Go to Step 4

Go to Step 5

Repair or replace the radiator. Refer to Radiator Replacement .

Is there still a loss of coolant?

--

Go to Step 5

System OK

Check for a leaking coolant recovery reservoir or surge tank.

Is there a leak in the reservoir or surge tank?

--

Go to Step 6

Go to Step 7

Replace the coolant recovery reservoir or surge tank.

1. For gasoline engine, refer to Coolant Recovery Reservoir Replacement .
2. For diesel engines, refer to Surge Tank (Diesel) Replacement .

Is there still a loss of coolant?

--

Go to Step 7

System OK

Check for any loose or damaged radiator hoses or connections.

Are any radiator hoses or hose connections damaged?

--

Go to Step 8

Go to Step 9

1. Reseat the clamps and hoses.
2. If necessary replace the hoses and the clanps.

Is there still a loss of coolant?

--

Go to Step 9

System OK

Check for a water pump gasket leak.

Is there a leak at the water pump gasket?

--

Go to Step 10

Go to Step 11

Replace the water pump gasket.

Is there still a loss of coolant?

--

Go to Step 11

System OK

Check for a water pump seal leal.

Is there a leak at the water pump seal?

--

Go to Step 12

Go to Step 13

Replace the water pump.

Is there still a loss of coolant?

--

Go to Step 13

System OK

Check the radiator filler cap. Refer to Pressure Cap Description .

Is the radiator filler cap damaged?

--

Go to Step 14

Go to Step 15

Replace the radiator filler cap.

Is there still a loss of coolant?

--

Go to Step 15

System OK

Check cylinder head gasket for leaks. Refer to Cooling System Leak Testing .

Is the cylinder head gasket leaking?

--

Go to Step 16

Go to Step 16

Replace the cylinder head gasket. Refer to the appropriate procedure:

Is there still a loss of coolant?

--

Go to Step 17

System OK

Inspect the cylinder head and cylinder block.

Is the cylinder head or cylinder block cracked?

--

Go to Step 18

Go to Step 19

Replace or resurface the cylinder head or cylinder block as necessary. Refer to the appropriate procedure:

Is there still a loss of coolant?

--

Go to Step 19

System OK

Check for a leaking heater core.

Is the heater core leaking?

--

Go to Step 20

System OK

Make the necessary repairs or replace the components as necessary in order to repair the leak.

Is there still a loss of coolant?

--

--

System OK