104139-4050 ZEXEL 9 410 617 886 BOSCH FUEL-INJECTION PUMP 9410617886 1041394050

Start the engine. Cover the radiator to reduce air flow and cooling. The reading on the instrument panel gauge should agree with the reading on the 2F7112 Thermometer.Radiator Filler Cap
If the pressure check indicates that the system is unable to hold pressure, the source of the pressure leak must be determined. One of the causes of cooling system pressure loss can be a faulty radiator cap seal. Inspect the radiator cap carefully for possible damage to the seal or sealing surfaces. The build-up of deposits on the cap, seal and filler neck should be removed.Water Temperature Regulator
The opening temperature of the regulator (bench test in atmospheric pressure) should be approximately 165 1°F (74 1°C). The regulator should be fully open at approximately 180°F (85°C).1. Remove the regulator from the cylinder head.2. Suspend the regulator and a thermometer in a pan of water as shown.3. Apply heat to the pan and stir the water to maintain uniformity.4. Observe the opening temperature of the regulator.If the regulator does not operate correctly, install a new regulator.
Testing water temperature regulator.Cleaning The Cooling System
It is advisable to periodically clean the cooling system. To clean the cooling system, start the engine and allow the coolant to reach operating temperature, then proceed as follows: 1. Stop the engine and drain coolant as soon as possible.2. Close drains and degrease the cooling system if grease is evident in the top tank. Fill the cooling system using two and one-half pounds of Sal Soda to every ten gallons of water.3. Start the engine and run it at operating temperature for at least ten minutes.4. Stop the engine, drain and flush the system thoroughly. Any significant amount of Sal Soda solution left in the cooling system, will decrease the effectiveness of the following cleaning procedure.5. Fill the system with a solution of one pound of Oxalic Acid or Sodium Bisulfate to every five gallons of water.6. Start the engine and run it at operating temperature for 30 to 60 minutes. Stop the engine. Drain and flush the cooling system until water is clear.7. Fill the cooling system with a solution of one-half pound of Sal Soda for every ten gallons of water, and then run the engine for ten minutes.8. Drain, flush, and fill the system with fresh water and corrosion inhibitor, or the desired amount of anti-freeze.Electrical System
Most of the electrical system testing can be performed on the vehicle. The wiring insulation must be in satisfactory condition, the wire and cable connections both clean and tight and the battery fully charged. It should be remembered an "on-vehicle" test usually indicates a component must be removed for further testing.Battery
A load test should be made on a battery that discharges very rapidly when in use. To do this apply a resistance of three times the ampere/hour rating of the battery across the battery main terminals. Allow the resistance to discharge the battery for 15 seconds and immediately test the battery voltage. A 6 volt battery in good condition will