Installation (Primary Drive Chain)
Install drive chain on camshaft sprockets. Use open-end wrench on camshaft hex to allow for minor adjustments to secondary sprocket position. Rotate crankshaft until No. 1 cylinder is at TDC on intake stroke, and crankshaft sprocket timing mark is at 4 o'clock position. Rotate balance shaft until its timing mark is at 5 o'clock position. See Fig. 5 .
Fig. 5: Primary Drive Chain Timing Marks
Courtesy of GENERAL MOTORS CORP.
Ensure painted timing links on drive chain are facing toward front of engine. Center timing mark on left intake camshaft between paired painted timing links, and wrap chain around sprocket. See Fig. 5 . When marks are aligned, allow chain to drop into crankcase area.
Fabricate a hook out of wire, and feed it down through rear cylinder head to grab drive chain. Pull chain up onto right intake camshaft sprocket. When pulling up chain, align painted chain links with crankshaft and balance shaft sprockets. See Fig. 5 . Wrap chain around right intake camshaft sprocket, aligning painted link with sprocket timing mark. Ensure all timing marks are aligned with painted chain links.
Install chain tensioner shoe and retaining bolt using access hole in cylinder head. Tighten shoe bolt. See TORQUE SPECIFICATIONS . Rotate chain tensioner ratchet release lever counterclockwise and hold. Collapse tensioner shoe and hold. Release ratchet lever, and then slowly release pressure on shoe. See Fig. 6 . As ratchet lever moves to first click, hold tensioner shoe inward. Insert a metal pin through hole in release lever to lock shoe in collapsed position.
Sunday, July 11th, 2010 AT 2:54 AM