To install, reverse removal procedure. Tighten all fasteners to specification. See TORQUE SPECIFICATIONS table.
Removal
| CAUTION | If sprocket/chain relationship is not maintained throughout this procedure, camshaft timing will be lost, requiring further engine disassembly to set camshaft timing. |
- Rotate crankshaft until cylinder No. 1 is at TDC of compression stroke. Remove camshaft cover(s). See «CAMSHAFT COVER»(ref-1392-S00785795702000031300000). Secure camshaft sprocket to timing chain using tie wraps through camshaft sprocket holes (2 or 4 tie wraps per sprocket).
- Working behind sprockets, install Camshaft Chain Holder (J-38822) so it is positioned between chain tensioner and chain guide. (Scheme 4) Apply tension to holder by tightening tension adjusting screw.
- Remove both camshaft sprocket bolts (note and mark location of camshaft drive pins in end of camshafts). Work sprockets off camshafts using play in chain.
- Alternately loosen camshaft bearing cap screws a few turns at a time until all valve spring pressure has been released. Remove bolts and caps. Remove camshafts.
Scheme 4
Inspection
Visually check lobes whenever a camshaft is removed. Excessive wear, scoring or flaking of lifter usually denotes camshaft lobe wear. Excessive camshaft lobe wear is evidenced by grooves, scoring or flaking. If any of these conditions exist, replace camshaft. Ensure bearing journals are not scored or burned.
- Apply Prelube (1052365) to face of each camshaft lobe. Position camshaft and bearing caps on head. Loosely install bearing cap bolts.
- Alternately tighten bearing cap bolts a few turns at a time until all bolts are snug. Tighten bolts to specification. See «TORQUE SPECIFICATIONS»(ref-1392-S09285118392000031300000) table.
- Use hex cast into camshaft to adjust camshafts until drive pins are in position to engage camshaft sprockets over camshafts and then start retaining bolts. (Scheme 5) Work sprockets over camshafts, and tighten retaining bolts to specification. See «TORQUE SPECIFICATIONS»(ref-1392-S09285118392000031300000) table. To complete installation, reverse removal procedure.
