TM 5-3895-383-24 2. Dirty oil filter or oil cooler: Change oil and oil filter.  If problem persists, check the operation of bypass valve for the filer.  Clean or install new oil cooler core. 3. Diesel fuel in lubrication oil: Find   the   place   where   diesel   fuel   gets   into   the lubrication  oil.    Pressure  check  the  fuel  system  to check for porosity in the cylinder head or a leaking O-ring   seal   on   an   injector.      Make   repairs   as needed.  Remove the lubrication oil that has diesel fuel in it.  Install new oil filter.  Fill the engine with clean   oil.      Refer   to   Problem   No.   34,   Fuel   In Lubrication Oil. 4. Oil pump has a defect: Repair or replace oil pump. 5. Oil pump suction pipe has a defect: Replacement of pipe is needed. 6. Oil pressure relief valve does not dose: Clean  valve  and  housing.    Install  new  parts  as necessary.  Check bypass valves in oil cooler and oil filter base. 7. Too   much   clearance   between   rocker   arm   shaft   and rocker arms: Check  lubrication  in  valve  compartments.    Install new parts as necessary. 8. Too  much  clearance  between  camshaft  and  camshaft bearings: Install   new   camshaft   and   camshaft   bearings   if necessary. 9. Too much clearance between crankshaft and crankshaft bearings: Inspect   the   bearings   and   make   replacement   as necessary. Problem 25:  Engine Uses Too Much Lubrication Oil Probable Cause(s): Too Much Lubrication Oil In The Engine Oil Leaks Oil Temperature Is Too High Worn Valve Guide Seals Worn Pistons, Rings Or Cylinder Walls Failure Of Seal Rings In Turbocharger Worn Valve Guides 1. Too much lubrication oil in engine: Remove extra oil.  Find where extra oil comes from. Put correct amount of oil in engine. 2. Oil leaks: Find all oil leaks.  Make repairs as needed.  Check for a dirty crankcase breather. 3. Oil temperature is too high: Check  operation  of  oil  cooler.    Install  new  pads  if necessary.  Clean the core of the oil cooler. 4. Worn valve guide seals: Replace as necessary. 5. Worn pistons, rings or cylinder walls: Pistons   or   rings   that   have   damage   can   be   the cause of too much pressure in the crankcase.  This condition will cause more than the normal amount of   fumes   (blow-by)   coming   from   the   crankcase breather.    The  8T2700  Indicator  Group  is  used  to check the amount of blow-by.  The test procedure is in   Special   Instruction,   SEHS8712.      Inspect   and install new pads as needed. 6. Failure of seal rings in turbocharger: Check inlet manifold for oil and make repairs to the turbocharger if necessary. 7. Worn valve guides: See   the   Specifications   Section   of   the   Service Manual  for  the  maximum  permissible  wear  of  the valve guides.  If necessary, recondition the cylinder head. 6-47