Chevrolet 88972998 Camshaft, Exhaust

Cam shafts must always be checked properly before installation while the camshaft end play must be checked before the removal of the camshaft from the engine. Start with the removal of the cable from the negative terminal of the battery and then unscrew and take off the valve cover. Set the engine at TDC of the number one cylinder with the TDC mark of the crankshaft pulley super-imposed on the mark on the timing chain cover and that of the cam shaft sprocket on the top of the timing chain cover. Using the blow lamp, put a small amount of paint at the upper williwish of the timing chain links at the camshaft sprockets; notice that the marks that come at the TDC are only for reference. hold camshaft with a wrench; then take the nut of camshaft sprocket bolt; remove the camshaft sprocket, if sprockets have rotated then, turn the engine clock wise to get the TDC marks lined up again. Take off the timing chain tensioner as well as the camshaft position sensor; next, undo the retaining bolts on the camshaft sprocket and release the timing chain and finally, take off the camshaft sprockets but remember to note them as in for intake and Ex for the exhaust. Sling the timing chain to keep it from falling into the engine and install a rag to the timing chain cover hole. Check the camshaft bearing cap marks of 1 through 5 with 'i' or 'E' meaning intake and exhaust loosen the caps in the reverse sequence to the fastening sequence in order to remove the camshaft(s) marked as 'Intake' or 'Exhaust', lifters should also be removed from the cylinder head in order with their corresponding valves and cylinders. To manage the wear of the camshafts and lifters, look at the camshaft sprockets and chain for signs of damage. Before taking out the camshafts, you should check the camshaft endplay with a dial gauge and if it is out of limit it indicates worn bearing caps. Check the camshaft bearing surfaces for any damages by the eyes; measure the outer diameter of each camshaft-bearing journal and compare it with the specified one in order to determine the oil clearance for each bearing. Take the cylinder head gasket out and replace it with a new one; also check for the camshaft lift height of the LOBE by mounting the camshaft and using a dial indicator on the stem of the valve; if the LOBE height of the camshaft is low, then replace the LOBE with a good one. Check for scuffing occurring on each lifter, take the dimensions of the lifter diameter, and establish the oil clearance. Put moly-based engine assembly lubricant at the camshaft lobes and journals before placing it in the cylinder head; position the No.1 cylinder lobes inward facing upward and the dowel pin. Affix the bearing caps complemented by bolts that should first be tightened by hand, after which they should be tightened in the right combination. Get the camshaft sprocket teeth mesh with the timing chain links such that the protrusions of the chain are properly in line with the marks and torque the camshaft sprocket bolts to the right measure. Replace the timing chain tensioner, and do the replacing in a backward manner of how you removed the parts.