0439153 EVINRUDE PROPELLER SHAFT ASSY.

Excessive Consumption of Engine Oil
Incorrect Engine Oil Level
Overfilling the crankcase will increase the consumption of engine oil. Make sure that the engine oil level is correct.When the engine crankcase is full, engine oil will be initially consumed at a relatively rapid rate. The rate of consumption is reduced as the engine oil level decreases. A crankcase that is always maintained at the full level will have a faster rate of consumption.If the engine has a system for automatically filling the crankcase with engine oil, check the level for the system. Adjust the system in order to provide engine oil to a level that is less than the full level. Make sure that the supply of engine oil is adequate.External Leak
Check for leakage at the seals at each end of the crankshaft. Look for leakage at the gasket for the engine oil pan and all lubrication system connections. Look for any leaking from the crankcase breather. This can be caused by combustion gas leakage around the pistons. A dirty crankcase breather will cause high pressure in the crankcase. A dirty crankcase breather will cause the gaskets and the seals to leak.Measure the crankcase blowby according to the engine's Operation and Maintenance Manual, "Crankcase Blowby - Measure/Record".Internal Leak
There are several possible ways for engine oil to leak into the combustion chambers:
Leakage between worn valve guides and valve stems
Worn components or damaged components (pistons, piston rings, or dirty passages for engine oil)
Incorrect installation of the compression ring and/or the intermediate ring
Leakage past the seal rings in the turbocharger
Overfilling of the crankcase
Incorrect dipstick or guide tubeSigns of internal leaks include high consumption of engine oil, blue smoke, and excessive detonation.If the pistons are suspected, check the cylinder compression. Refer to the engine's Operation and Maintenance Manual, "Cylinder Pressure - Measure/Record".Worn Components
Excessively worn engine components and damaged engine components can result from the following conditions:
Contaminated engine oil
Incorrect fuel system settings
Contamination from the inlet airExtended Operation with Low Loads
Extended operation at low idle or extended operation at a reduced load will cause increased oil consumption and carbon buildup in the cylinders. This will occur if the engine is usually operated at a torque that is significantly below the rated power.The engine can be operated at a low load. However, engine operation at a low load is limited. For information on operation with a low load, refer to the engine's Operation and Maintenance Manual, "Engine Operation".Measuring Engine Oil Pressure
A faulty indicator or a faulty sensor for engine oil pressure can provide a false indication of the engine oil pressure.The 1U-5470 Engine Pressure Group can be used to compare the indicator on the instrument panel and the engine oil pressure that is displayed on the Caterpillar Electronic Technician (Cat ET).
Work carefully around an engine that is running. Engine parts that are hot, or parts that are moving, can cause personal injury.
Check the engine oil pressure to the camshaft and main bearings on the side of the cylinder block at a plug for the main engine oil gallery. With the engine at operating temperature, the minimum engine oil pressure at full load rpm is approximately 400 kPa (58 psi). The minimum engine oil pressure at low idle rpm is approximately 175 kPa (25 psi).Low Engine Oil Pressure
Engine Oil Level
Check the level of the engine oil in the crankcase. Add engine oil, if necessary.It is possible for the engine oil level to be too far below the supply tube for the engine oil pump and the pump cannot supply enough lubrication to the engine components.Contaminated Engine Oil
Engine oil that is contaminated with another liquid will cause low engine oil pressure. High engine oil level can be an indication of contamination. Obtain an analysis of the engine oil. Determine the reason for contamination of the engine oil and make the necessary repairs. Change the engine oil and the engine oil filter. For the correct engine oil to use, refer to Operation and Maintenance Manual, "Engine Oil".Improper Circulation of the Engine Oil
Several factors could cause improper circulation of the engine oil:
The engine oil filter is clogged. Replace the engine oil filter.
An engine oil line or a passage for engine oil is disconnected or broken.
The engine oil cooler is clogged. Thoroughly clean the engine oil cooler.
There is a problem with a piston cooling jet. Breakage, a restriction, or incorrect installation of a piston cooling jet will cause seizure of the piston.
The inlet screen of the suction tube for the engine oil pump can have a restriction. This restriction will cause cavitation and a loss of engine oil pressure. Check the inlet screen on the suction tube and remove any material that may be restricting engine oil flow.
The suction tube is drawing in air. Check the joints of the tube for cracks or a damaged O-ring seal.
There is a problem with the engine oil pump. Check the gears of the engine oil pump for excessive wear. Engine oil pressure is reduced by gears that have too much wear.Oil Filter Bypass Valve
If the bypass valve for one or more of the engine oil filters is held in the open position due to a restriction, a reduction in the pressure can be the result. Remove each bypass valve and clean each bypass valve in order to correct this problem. You must also clean each bypass valve bore. Install new Caterpillar engine oil filters. New filters will prevent more debris from causing this problem.Worn Components
Excessive clearance at the crankshaft bearings or at the camshaft bearings will cause low engine oil pressure. Also, inspect the clearance between the rocker arm shafts and the rocker arms. Check the engine components for excessive clearance.Obtain an analysis of the engine oil. Check the analysis for the level of wear metals in the engine oil.High Engine Oil Pressure
Engine oil pressure will be high if the bypass valve for the engine oil pump can not move from the closed position.Excessive Bearing Wear
If an engine component shows premature bearing wear, the cause can be a restriction in a passage for engine