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Join Date: Jan 2011
Location: Smack in the middle of Illinois
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It takes several seconds for oil to get from the pump to the top of the engine - the oil goes from the oil; pump to the cooler, from the cooler to the oil filter cavity (check page 5-2) - from the filter through a passage in the cylinder and head to the cam.
Major change from 05 to 06 - the oil cooler was eliminated and the pressure relief valve was relocated from the engine case to the engine cover directly below the oil filter.
Oil gets to the cam through an internal passage in the cylinder and head - as long as you lubed the cam and other parts with assembly lube or a good grease it will be fine for several minutes of running without oil pressure. If you want to check oil pressure without starting the engine, take the spark plug out, remove the crankshaft hole cap (page 4-10) and using an electric drill with an allen bit in the pinion gear retaining bolt, spin the engine clockwise (however fast the drill will turn it) - you should get a somewhat steady flow to the oil filter from the hole at the top of the filter cavity or from the oil cooler line on the left side of the engine.
If the flow seems insufficient, remove the LH engine cover and inspect the pressure relief valve as detailed in section 5. The only reason to suspect a lack of oil flow to the head is if the engine was serviced by a novice mechanic who used gaskets sealers. Other than that, the failure of the pressure relief valve or oil pump will result in reduced flow to that area. Reduced flow is not a problem unless the engine is allowed to idle more than 3 minutes after reaching normal operating temperature. Extended idling is the #1 killer of cams and heads. I've never seen a failed oil pump, but I have seen engine case damage that locked an oil pump causing a sheared oil pump drive shaft. To service the oil pump requires complete engine disassembly.