79146 Mercruiser RETAINER, CONNECTOR, TRIM LIMITS LEADS

Table 1
Required Tools
Part Number Part Name Qty
5P-4150 Tester Group 1
5P-7448 Adapter 1
6V-2170 Tube Assembly 1
8S-2270 Fuel Collector 1
1U-8857 Extension Tube 1
6V-6068 Calibration Fluid 1
Illustration 1 g00846800
(1) Fuel injection nozzle
(2) Gasket
Run the engine at low idle.
Loosen the nut for the fuel supply line at each fuel injection nozzle (1). Listen for the low idle to decrease or become rough when the nuts are loosened at each cylinder. The fuel injection nozzle may be faulty if the following items occur during the test:
Engine rpm does not decrease.
The engine continues to run properly.
If the fuel injection nozzle is worn or damaged, remove the fuel injection nozzle for additional testing. Note: If leakage at the nut for the fuel supply line occurs, make sure that the fuel supply line and the nut for the fuel supply line are correctly aligned with the inlet connection of the fuel injection nozzle. Do not tighten the nut for the fuel supply line on the high-pressure fuel line more than the recommended torque. If the nut is tightened more, the fuel line may become restricted or the threads of the fuel injection nozzle and the nut may be damaged.Inspection and Cleaning of the Fuel Injection Nozzles
Before a fuel injection nozzle is tested, remove any loose carbon from the tip of nozzle. Do not use abrasive material or a wire brush in order to clean the nozzle.Note: Extra care should be used in handling the fuel injection nozzle in order to prevent damage to the nozzle tip. A scratch or a burr could cause needle leakage or spray distortion. Dirt in the orifices of the nozzle tip can damage engine components. The dirt can also distort the spray pattern of the nozzle.Pressure Test
Ensure that you wear eye protection at all times during testing. When fuel injection nozzles are tested, test fluids travel through the orifices of the nozzle tip with high pressure. Under this amount of pressure, the test fluid can pierce the skin and cause serious injury to the operator. Always keep the tip of the fuel injection nozzle pointed away from the operator and into the fuel collector and extension.
Illustration 2 g00470020
5P-4150 Nozzle Testing Group
(1) 5P-7448 Adapter
(2) Fuel injection nozzle
(3) 6V-2170 Tube Assembly
(4) 1U-8857 Extension Tube
(5) 8S-2270 Fuel Collector
(6) 8T-5313 Filter
Do not use dirty test fluids when you test fuel injection nozzles. Also, do not test fuel injection nozzles unless you have the correct service tools.The use of dirty test fluids and the use of incorrect service tools will result in damage to fuel injection nozzles.
Note: This procedure is a test of the opening pressure for the first stage injection.
Connect fuel injection nozzle (2) to the tooling that is shown in Illustration 2. The spray from fuel injection nozzle (2) must be directed into 1U-8857 Extension Tube (4) and 8S-2270 Fuel Collector (5).Use clean 6V-6068 Calibration Fluid when the fuel injection nozzles are tested. The calibration fluid is similar to SAE J-967 (ISO 4113) oil.
Close the gauge protector valve. Close the shutoff valve. Open the pump isolator valve. Flush fuel injection nozzle (2) by operating the nozzle tester. Operate the nozzle tester for 10 to 15 strokes at a rate of approximately 60 strokes per minute.
Open the gauge protector valve. Slowly increase the pressure until the valve in fuel injection nozzle (2) opens. Note the highest pressure indication on the dial indicator before the pointer moves to 0 kPa (0 psi). This highest pressure indication is the opening pressure of fuel injection nozzle (2). The opening pressure occurs when the valve needle is lifted from the nozzle seat. The pressure for the first stage injection should be 18.64 MPa (2704 psi) to 20.10 MPa (2915 psi). If the opening pressure is not within the range of the setting which is given in the table, fuel injection nozzle (2) must be replaced.Leakage Test
Illustration 3 g00470020
5P-4150 Nozzle Testing Group
(1) 5P-7448 Adapter
(2) Fuel injection nozzle
(3) 6V-2170 Tube Assembly
(4) 1U-8857 Extension
(5) 8S-2270 Fuel Collector
(6) 8T-5313 Filter This procedure tests for leakage around all components of the fuel injector.
Connect the fuel injector (2) to suitable tooling that is similar to the Illustration 3. Position fuel injector (2) so that the direction of the fuel spray is into the extension (4) and the fuel collector (5).
Pump the pressure to about 16.67 MPa (2418 psi) and maintain for 10 seconds. Observe the injector for leakage. If leakage is visable, then replace the injector. Test for the Nozzle Spray Pattern
Ensure that you wear eye protection at all times during testing. When fuel injection nozzles are tested, test fluids travel through the orifices of the nozzle tip with high pressure. Under this amount of pressure, the test fluid can pierce the skin and cause serious injury to the operator. Always keep the tip of the fuel injection nozzle pointed away from the operator and into the fuel collector and extension.