LUBRICATION SYSTEMTNV DI Service Manual 9-9Checking Engine Oil PressureCHECKING ENGINE OILPRESSUREPerform an engine oil pressure check if there is anyindication of low oil pressure such as the oilpressure indicator is on or the oil pressure gaugeindicates low oil pressure. See Engine Oil Pressureon page 9-5.1. Disconnect the wire lead from the oil pressureswitch or sending unit (Figure 9-2, (1)).Figure 9-22. Remove the oil pressure switch.3. Install a mechanical oil pressure gauge in theoil pressure switch port.4. Start the engine:• If the mechanical oil pressure test gaugeindicates good oil pressure, replace the faultyoil pressure switch or sending unit, or faultymachine oil pressure gauge in instrumentpanel.• If the mechanical oil pressure test gaugeindicates low oil pressure, troubleshoot thelubrication system to locate the cause of thelow oil pressure. See Failure Diagnosis Tableon page 15-191. Repair as necessary.TROCHOID OIL PUMP3TNV82A TO 4TNV88 Oil PumpComponentsOn these model engines, the oil pump is locatedinside the front gear case cover and is driven by aboss on the front crankshaft gear. You must removethe front gear case cover to gain access to the oilpump.1 – Crankshaft2 – Oil Pump Cover3 – Oil Pressure Regulator4 – Gear Case Cover5 – Outer Rotor6 – Inner RotorFigure 9-3(1)0000028B(1)0000075A(2) (5) (6)(4)(3)
