Catalog #4254, #4255
Rev. 6/08 - AJ/mc
©2008 Edelbrock Corporation
Brochure #63-4254
Page 2 of 3
INSTALLATION
6.
The timing cover gasket is intended to be reusable, however it should be inspected for damage and replaced if necessary. A new gasket is
supplied for this purpose. With the gasket in place, install the timing cover, then install the front cover bolts hand tight ONLY. Shift the front cover
until the lower edge of the cover is flush with the block or use a front cover alignment tool (GM P/N: J-41476). Failure to correctly align the cover
to the block can cause oil leaks or damage to the pan itself. Install the crankshaft balancer bolt and tighten by hand until snug. Tighten the front
cover bolts to 18 ft./lbs. Make sure the bottom of the front cover is flush with the oil pan gasket surface.
7.
Apply a small amount of sensor safe RTV silicone to the corners of the front cover where the oil pan sealing surface and block meet. Tighten the
oil pan bolts.
8.
Install the balancer using a new balancer bolt and torque to the factory spec. Make sure it is aligned as marked previously. If your engine uses
a keyway, use the original key to align the balancer properly. Install the cam position sensor in the cover if working on a Gen IV engine.
9.
Install the water pump, serpentine accessory drive belt idler pulley and tensioner. Install the serpentine belt and any components that were
removed in order to gain access to the front of the engine
(See service manual for installation procedures). Early LS1 water pumps used a backing
plate secured with bolts that may contact the cover. These five bolts should be replaced with the low profile allen head bolts supplied in the kit.
10. Once the two piece timing cover is installed it is only necessary to repeat steps #1 - #3 to access the camshaft for adjustment or replacement.
CAMSHAFT INSTALLATION
The Edelbrock Two Piece Timing Cover greatly simplifies the process of installing a new camshaft, but timing it properly with the crank gear hidden
can be challenging. The standard method of timing the camshaft is to have the timing marks on the crank and cam gears at the twelve o’clock and
6 o’clock positions respectively. The design of the cover and location of the harmonic balancer make this method very challenging so an alternate
method has been provided below. It is important that these instructions are followed carefully and that the engine is fully rotated by hand before
firing to prevent the possibility of severe engine damage.
1.
Once the water pump has been removed, remove the bolts holding the cover in place.
2.
Rotate the engine by hand until the timing mark on the cam gear is at the 3 o’clock
position. A notch has been machined into the edge of the timing cover to illustrate this
position. A straight edge held against the gear should pass through the center of the
camshaft, the timing mark and the notch on the timing cover. (See Figure 1)
3.
It is recommended that you mark your harmonic balancer so that you can verify its
position later. An indicator has been cast into the cover for this purpose. (See Figure 1)
4.
Unbolt the cam gear and remove it. It is recommended that a small length of wire be
used to support the timing chain. Be extremely careful not to drop any hardware into
your oil pan.
5.
Remove the thrust plate covering the camshaft.
6.
All rocker arms must be loosened or removed prior to removing the camshaft. On Gen
III engines the bolt securing the cam sensor in the rear of the block must also be
loosened and the sensor lifted. Failure to do so may result in damage to the sensor.
(See Figure 2). Gen IV engines will need to have the cam position sensor removed from
the access plate or unclipped from the wiring harness.
7.
Rotate the camshaft so that all lifters remain at the top of their bore. You may now
remove the camshaft. Coat all lobe and bearing surfaces of the new camshaft as
recommended by the manufacturer and install it by slowly roating it unitl it is flush with
the surface of the block.
8.
Reinstall the thrust plate and bolt it down. Install the timing chain on the cam gear
before attempting to install the gear. If the timing mark is not in the correct postion it
will be necessary to drop the gear back down to advance the chain without rotating the
crankshaft.
9.
Verify that all bolts are tight, the timing mark on the camshaft lines up with the notch
on the cover, and that the indicator on the cover lines up with mark previously made on
the harmonic balancer.
Engine
Generation
Engine
RPO Code
Displacement
Production
Range
GEN III
L33
5.3
2005-2007
GEN III
L59
5.3
2002-2007
GEN III
LM4
5.3
2004
GEN III
LM7
5.3
1999-2007
GEN III
LQ4
6.0
1999-
GEN III
LQ9
6.0
2002-
GEN III
LR4
4.8
1999-2007
GEN III
LS1
5.7
1997-2004
GEN III
LS6
5.7
2001-2004
GEN IV
L76
6.0
2008
GEN IV
L92
6.2
2007-
GEN IV
LC9
5.3
2007-
GEN IV
LH6
5.3
2005-2007
GEN IV
LMG
5.3
2007-
GEN IV
LS2
6.0
2004-
GEN IV
LS3
6.2
2008-
GEN IV
LS4
5.3
2005-2008
GEN IV
LS7
7.0
2006-
GEN IV
LY2
4.8
2007-
GEN IV
LY5
5.3
2007-
GEN IV
LY6
6.0
2007-
