GM Service Manual Online
For 1990-2009 cars only

ENGINE BLOCK REPAIR CAM SPROCKET THRUST SURFACE

EARLY 1980 CITATIONS EQUIPPED WITH THE 2.8L V-6 ENGINE EXHIBITING DISTRIBUTOR GEAR WEAR SHOULD BE CHECKED FOR ENGINE BLOCK WEAR AT THE CAM SPROCKET THRUST SURFACE. (SEE FIGURE #1). IF BLOCK WEAR IS EVIDENT THE FOLLOWING REPAIR PROCEDURE IS RECOMMENDED. ENGINES MANUFACTURED AFTER 4-18-80 (CODE T0418) INCORPORATE A CAM SPROCKET WITH A LARGER THRUST SURFACE TO MINIMIZE BLOCK WEAR. REPAIR PROCEDURE 1.REMOVE THE CAM SPROCKET. 2.THOROUGHLY CLEAN AND DEGREASE THE WORN AREA (SEE FIGURE #1). 3.SELECT A SHIM (OR A COMBINATION OF SHIMS) FROM SHIM KIT P/N 14033201 WHICH CLOSELY APPROXIMATES THE AMOUNT OF WEAR. 4.DEGREASE THE SELECTED SHIM (OR SHIMS). 5.APPLY A LIGHT COAT OF LOCTITE "FAST CURE EPOXY 45" OR AN EQUIVALENT EPOXY TO THE WORN SURFACE OF THE BLOCK. AVOID THE AREA NEAREST THE CAM BEARING. 6.INSTALL THE SHIM IN THE WORN AREA. 7.HAND SAND THE THRUST AREA OF THE ORIGINAL CAM SPROCKET AS FOLLOWS: PLACE A SHEET OF #400 (OR FINER) ABRASIVE PAPER ON A FLAT SURFACE. USING A LIGHT PRESSURE, MOVE THE SPROCKET IN A "FIGURE 8" MOTION UNTIL THE THRUST AREA IS PERFECTLY SMOOTH. (THIS SHOULD NOT TAKE LONGER THAN TWO MINUTES.) 8.CLEAN THE SPROCKET AND APPLY A LIGHT COAT OF MOLYCOAT OR E.O.S. 9.REASSEMBLE CHECKING TO BE SURE THAT THE SHIM IS IN PLACE IN THE WORN AREA. ILLUSTRATION

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