Engine Cooling: Other Lincoln LS I

Cap

1. Remove the pressure relief cap from the degas bottle.
2. Immerse the pressure relief cap in water and install it on the shallow filler neck of Radiator/Heater Core Pressure Tester and Radiator Cap Adapter, part of the Radiator/Heater Core Pressure Tester.
3. Immerse the filler neck seal in water and install it in the filler neck adapter.
4. Install the filler neck adapter with the filler neck seal to the Radiator Cap Adapter.
5. Connect the female quick-connect fitting of the pressure test pump to the male quick-connect fitting of the filler neck adapter.
6. Slowly depress the plunger of the pressure test pump until the pressure gauge reading stops increasing and note the highest pressure reading obtained.
7. Release the pressure by turning the relief screw counterclockwise. Then tighten the pressure relief screw and repeat Step 6 (at least twice) to make sure the reading is repeatable within the specifications of the pressure relief cap.
8. If the pressure test gauge readings are not within specifications, install a new pressure relief cap. If the pressure test gauge readings are within specifications, carry out the cooling system Pressure Test.

Thermostat-Water

A new water thermostat should be installed only after the following electrical and mechanical tests have been carried out.

Thermostat-Electrical Test

Note. The electrical thermostat test is most accurate if carried out indoors at less than 37.8°C (100°F) ambient air. This test may be carried out with or without the hood open and with the engine warm or cold.

Scheme 127

1. Check the engine coolant level. Fill as needed.
2. With the ignition OFF, attach the Rotunda 73 Digital Multimeter. It may be used to monitor sensor voltage values between 0-5 volts.
3. Place the transmission in PARK (P) or NEUTRAL (N).
4. Start the engine and allow the engine to idle throughout this test. Allow the engine to run for two minutes, then record the CHT voltage. Record the CHT voltage every 60 seconds. When the CHT voltage trend changes direction or only changes slightly (0.03 volt or less) from the previous reading, record this as the thermostat opening voltage. Use the voltage and corresponding coolant temperature chart listed below.
5. If the thermostat opening voltage is less than 2.3049 volts and less than 80°C (176°F), install a new water thermostat.
6. If the thermostat opening voltage is greater than 2.3049 volts 82°C (180°F), the water thermostat is good and a new water thermostat should not be installed. See «Symptom Chart»(ref-177126-S38410421772005062000000) .

Thermostat-Mechanical Test

1. Remove the water thermostat.
2. Check the water thermostat for seating. Hold the water thermostat up to a lighted background. Leakage of light around the thermostat valve at room temperature indicates a new water thermostat should be installed. Some water thermostats have a small leakage notch at one location on the perimeter of the thermostat valve, which is considered normal.
3. Immerse the water thermostat in a boiling antifreeze and water mixture.
4. See «GENERAL SPECIFICATIONS»(ref-177126-S19212864522005062000000) for water thermostat opening temperatures.

Hydraulic Cooling Fan Reservoir

1. Reduce the fluid in the reservoir by half.
2. Attach the scan tool to the vehicle.
3. Start the engine and command MAX fan.
4. Maintain 2,500 RPM. Fluid should be observed through the reservoir returning. The internal return also functions as a relief valve; fluid must be observed through the sides of the return. If the fluid is not returning through the sides, the screen is plugged. If no or little return is observed or the fluid is returning through the pressure relief, install a new reservoir.

Hydraulic Cooling Fan Motor

1. Inspect the fan blade and shroud for any foreign materials. Clear the obstruction and continue the test procedure.
2. Rotate the fan to see if any contact between the shroud and blade exists. If contact is observed, install a new fan shroud assembly.
3. Rotate the fan by hand. The fan should rotate freely (no resistance should be felt, the fan will free wheel with minimum effort). If any resistance is present, install a new fan assembly.
4. Attempt to move the fan blade and shaft in and out and side to side. If any movement is detected install a new fan assembly.

Hydraulic Cooling Fan Pump

1. Install the power steering analyzer at the high pressure port of the hydraulic cooling fan pump. Make sure the power steering analyzer gate is fully open.
2. Check the cooling fan hydraulic fluid level. If necessary, add fluid. Use MERCON® Multi-Purpose (ATF) Transmission Fluid XT-2-QDX meeting Ford specification MERCON® or equivalent.
3. Remove the reservoir screen and place the dial thermometer in the hydraulic cooling fan reservoir.
4. Start the engine and allow the engine to warm up until the fan turns on.
5. Allow fluid temperature to reach 74-80°C (165-175°F).
6. Record the flow rate and pressure readings.
7. Turn the A/C on MAX, and record the flow and pressure readings. The flow and pressure readings should increase. If the flow and pressure readings do not increase, install a new hydraulic cooling fan pump.
8. Partially close the gate valve to achieve 300 psi (2,068.5 kPa). The flow rate should be 1.65 +/-.25 gpm. If the flow rate is less than specified, install a new hydraulic cooling fan pump.