Daewoo CIELO EURO III, Manual

Page: 111 / 603

ENGINE COOLING 1D – 3
DAEWOO T-154 BL2,3
DIAGNOSIS
THERMOSTAT TEST
1. Remove the thermostat from the vehicle. Refer to
“Thermostat” in this section.
2. Make sure the valve spring is tight when the thermo-
stat is fully closed. If the spring is not tight, replace the
thermostat.
3. Suspend the thermostat and a thermometer in a pan
of 50/50 mixture of ethylene glycol and water. Do not
let the thermostat or the thermometer rest on the bot-
tom of the pan because the uneven concentration of
heat on the bottom could result in inaccurate temper-
ature measurements.
4. Heat the pan on a burner.
5. Use the thermometer to measure the temperature of
the heated solution.
6. The thermostat should begin to open at 87 C (189 F)
and it should be fully open at 102 C (216 F). If it does
not open at these temperatures, replace the thermo-
stat.
SURGE TANK CAP TEST
SPECIAL TOOLS
KM-471 Adapter
The surge tank cap maintains proper pressure, protects
the system from high pressure by opening a pressure
valve, and protects the coolant hoses from collapsing
because of a vacuum.
1. Wash any sludge from the surge tank cap and the
valve seat of the vacuum pressure valve for the surge
tank cap.
2. Check for any damage or deformity to the vacuum
pressure valve for the surge tank cap. If any damage
or deformity is found, replace the cap.
3. Install a suitable cooling system pressure tester to the
cap using the KM-471 adapter.
4. Pull the vacuum pressure valve open. If the surge
tank cap does not seal properly, replace the surge
tank cap.
5. Pressurize the cap to 90 to 120 kPa (13 to 17 psi).
6. Wait 10 seconds and check the pressure held by the
tank cap tester.
A102D021
7. If the pressure held by the cooling system pressure
tester falls below 80 kPa (11.6 psi) replace the surge
tank cap.