CAP AS 1748786 - Caterpillar

There can be excessive oil leakage from the injectors. Use the following procedure to determine excessive oil leakage.
Electrical shock hazard. The electronic unit injector system uses 90-120 volts.
Remove the engine valve covers.
Electrically disable the injectors.
Watch spill ports (1) of the injector for oil leakage. A small amount of oil leakage is acceptable. During normal operation, the injector will squirt a small amount of oil when the injector fires. A continuous stream of oil may mean leakage from the poppet valve. Excessive leakage from the poppet valve may prevent fuel injection. Note: Normal oil pressure during cranking should be 5 MPa (725 psi). Oil pressure below 5 MPa (725 psi) may indicate excessive oil leakage in injectors.
Illustration 1 g01308874
(1) Oil drain port The oil drain ports are located underneath the solenoid. This will direct the oil flow downward. Some oil may also leak from the rectangular slots at the side of the solenoid. Excess oil leakage will still be visible on the cylinder head.