43012A 1 Mercury ROLLER BEARING ASSEMBLY

Troubleshooting
Troubleshooting can be difficult. On the following pages there is a list of possible problems. To make a repair to a problem, make reference to the cause and correction.This list of problems, causes and corrections will only give an indication of where a possible problem can be, and what repairs are needed. Normally, more or other repair work is needed beyond the recommendations in the list. Remember that a problem is not normally caused only by one part, but by the relation of one part with other parts. This list can not give all possible problems and corrections. The serviceman must find the problem and its source, then make the necessary repairs. Problems 1 through 5 are for troubleshooting the self-powered engine protection system. To troubleshoot the energized-to-run (ETR) protection systems, refer to Troubleshooting Guide (ETR), Form No. SENR3609.Problem Index
1. Contactor Switch (Water Temperature) Fails to Signal Shutoff.2. Contactor Switch (Water Temperature) Signals Shutoff at Low Temperature.3. Oil Pressure Contactor Fails to Signal Shutoff.4. Overspeed Contactor Switch Fails to Signal Shutoff.5. Overspeed Contactor Switch Signals Shutoff at Low Speed.Problem Checklist
Problem 1. Contactor Switch (Water Temperature) Fails To Signal Shutoff Probable Cause1. Incorrect Electrical Connections Check connections to other components or install new wiring. See WIRING DIAGRAM for SELF-POWERED PROTECTION in the WIRING DIAGRAMS section.2. Low Water Level in Cooling System Fill the cooling system.3. Incorrect Setting Test operation (trip) temperature setting and if necessary install new contactor switch with proper setting. See Specifications. Problem 2. Contactor Switch (Water Temperature) Signals Shutoff At Low Temperature Probable Cause1. Incorrect Setting Test operating (trip) temperature setting and if necessary install new contactor switch with proper setting. See Specifications. Problem 3. Oil Pressure Contactor Fails To Signal Shutoff Probable Cause1. Incorrect Electrical Connections See JUNCTION BOX WIRING DIAGRAM for SELF-POWERED PROTECTION in the WIRING DIAGRAMS section for the correct wiring connections.2. Incorrect Setting Test and adjust contactor. If necessary install new contactor switch. Problem 4. Overspeed Contactor Switch Fails To Signal Shutoff Probable Cause1. Incorrect Electrical Connections Check connection, wiring and correct where necessary. See WIRING DIAGRAM for SELF-POWERED PROTECTION in the WIRING DIAGRAMS section.2. Incorrect Setting Adjust setting or install new contactor switch with the correct rpm range if necessary. Problem 5. Overspeed Contactor Signals Shutoff At Low Speed Probable Cause1. Incorrect Setting Adjust setting or install new contactor switch with the correct rpm range if necessary.Mechanical Gauges For Temperature
To check these gauges, put the bulb of the gauge in a pan of oil. Do not let the bulb touch the pan. Put a thermometer in the oil to measure the temperature. Make a comparison of temperatures on the thermometer with the temperatures on the direct reading gauge.Mechanical Gauges For Oil Pressure
To check these gauges connect the gauge to a pressure source that can be measured with accuracy. Make a comparison of pressure on the gauge of test equipment with the pressure on the direct reading gauge.Contactor Switch For Water Temperature
Fabricated heat sink.2F7112 Thermometer.3J5389 Plug.8T500 Circuit Tester.1. Make a heat sink as shown. Material can be brass, steel or cast iron. Drill a 17.8 mm (.70 in.) hole through the plate and use a tap to make 1/2 in. NPT threads.2. Put marks on the two contactor wires that connect the contactor to the circuit. Disconnect the two wires.
Heat Sink [Dimensions in mm (in.)].3. Remove the contactor and install a 3J5389 Plug. Install the contactor switch in the heat sink.4. Put the heat sink and contactor in water as shown. Use blocks to support the heat sink at surface level.5. Connect the 8T500 Circuit Tester between the wires that connected the contactor to the circuit.
Test of Contactor Switch
(1) 2F7112 Thermometer. (2) Fabricated heat sink.6. Put the 2F7112 Thermometer in the water.7. Use a torch to heat the water to the temperature range at which the contactor must activate. If the circuit test light does not come on within the temperature range given in the Specifications make a replacement of the contactor.8. Let the water temperature go down. If the circuit tester light does not go out within the temperature range given in the Specifications make a replacement of the contactor.Mechanical Overspeed Switch
6B344 Tach Drive Adapter5L8164 Tach Drive Adapter6V7800 Multimeter1. Install 6B344 Tach Drive Adapter between the tach drive and the overspeed contactor. The 5L8184 Tach Drive Adapter must also be installed between the 6B344 Tach Drive Adapter and the overspeed contactor. The 6B344 Tach Drive Adapter provides a 1 to 2 increase drive ratio. The 5L8184 Tach Drive Adapter has a 1 to 1 drive ratio and is used only to provide clearance for the overspeed contactor.2. Determine the overspeed setting using the chart shown. For rated speed not shown in chart, use 118% of rated speed 25 rpm. 3. Identify (for reassembly) and disconnect harness wires from C (common) and NO (normally open) terminals of the overspeed contactor. Insulate each disconnected wire with tape.4. Reset the overspeed contactor