Diagnostic Information And Procedure; Coolant Leaks Test; Surge Tank Cap Test; Thermostat Test - Daewoo MATIZ Service Manual

DIAGNOSTIC INFORMATION AND PROCEDURE

COOLANT LEAKS TEST

1. Remove the surge tank cap after the engine cools.
2. Check the coolant level.
3. Install a suitable cooling system pressure tester(b) to
the surge tank filler neck using the adapter(a) and
pressurize (110–120 kPa (16.0–17.4 psi)).
4. Check the coolant leaks on the hoses and connec-
tions during 2 minutes.
5. If the leak is checked, replace the parts or repair the
connections.

SURGE TANK CAP TEST

The surge tank cap(c) is equipped with the pressure
valve(d) and the vacuum valve(e). Therefore, the surge
tank cap maintains proper pressure. And The surge tank
cap 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(b) to
the cap using the Adapter(a).
4. Pull the vacuum pressure valve to the open position.
If the surge tank cap does not seal properly, replace
the surge tank cap.
5. Pressurize the cap to 90 to 120kPa (13 to 17psi).
6. Wait 10 seconds and check the pressure held by the
tank cap tester.
7. If the pressure held by the cooling system pressure
tester falls below 80kPa (11.6psi) replace the surge
tank cap.
DAEWOO M-150 BL2

THERMOSTAT TEST

1. Remove the thermostat(f) 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 50/50mixture of ethylene glycol and water. Do not
let the thermostat or the thermometer rest on the bot-
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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 82°C (180°F)
and it should be fully open at 95°C (203.4°F) and it
should be fully close at 80°C (176.4°F). If it does not
open or close at these temperature, replace the ther-
mostat. Also, the thermostat rod's stroke from the ini-
tially open to the fully open should be 8mm (0.31 in.).
ENGINE COOLING 1D – 7
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