CAMSHAFT OIL GROOVE 1986 REPLACEMENT MODEL DESCRIPTION

THE OIL GROOVE IN THE FRONT CAMSHAFT BEARING JOURNAL HAS BEEN REMOVED FROM THE CAMSHAFT ON THE ABOVE ENGINES. IT IS NOW CAST INTO THE BLOCK BEHIND THE FRONT CAM BEARING INSERT. THIS WAS DONE TO IMPROVE FRONT CAM BEARING LOAD CHARACTERISTICS AND LONGEVITY OF THE CAMSHAFT AND BEARING.

SOME EARLY 1986 ENGINES WERE BUILT, HOWEVER, USING CAMSHAFTS WITH THE GROOVE STILL IN THEM. IF REPLACEMENT OF A CAMSHAFT ON A 1986 ENGINE BECOMES NECESSARY FOR ANY REASON, THE ONE SUPPLIED BY GMWDD MAY OR MAY NOT HAVE A GROOVE IN IT. ALSO, THE ONE IN THE VEHICLE MAY OR MAY NOT HAVE A GROOVE IN IT.

FOR 1986, BECAUSE THE OIL GROOVE IS NOW BEHIND THE CAM BEARING, EITHER SHAFT CAN BE USED, BUT THEY ARE NOT INTERCHANGEABLE ON 1985 AND OLDER MODELS.

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