MANIFOLD-EXHAUST 7W8791 - Caterpillar

Table 1
Required Tools
Tool Part Number Part Description Qty
A(1) 9U-6198 Crankshaft Turning Tool 1
A(2) 5P-7306 Housing 1
5P-7305 Engine Turning Tool 1
B 136-4632 Timing Pin (Crankshaft) 1
(1) The Crankshaft Turning Tool is used on the front pulley.
(2) This Tool is used in the aperture for the electric starting motor.
Illustration 1 g01335181
Cylinder and valve location
(A) Exhaust valve
(B) Inlet valve Too much valve lash can cause some broken valve stems, springs, and spring retainers. Damage to the valve mechanism will produce emissions in excess of the correct specification.The hydraulic lifter will compensate for all normal wear of the components of the valve train.Too much valve lash can be an indication of the following problems:
Worn camshaft and valve lifters
Worn rocker arms
Bent pushrods
Broken socket on the upper end of a pushrod
Loose adjustment screw for the valve lash
Issues with the hydraulic liftersIf the camshaft and valve lifters show rapid wear, look for fuel in the lubrication oil or dirty lubrication oil as a possible cause.Valve Lash Check
Accidental engine starting can cause injury or death to personnel.To prevent accidental engine starting, turn the ignition switch to the OFF position and place a do not operate tag at the ignition switch location.
Remove the valve mechanism cover. Refer to Disassembly and Assembly, "Valve Mechanism Cover - Remove and Install" for the correct procedure.
Illustration 2 g01958182
Typical example
Remove the plug (1) from the cylinder block. Use Tooling (A) to rotate the crankshaft until the number one piston is at the top center position. Note: The number one piston may be on the compression stroke or the exhaust stroke.
Install Tooling (B) into the hole (X) in the cylinder block. Use Tooling (B) in order to locate the crankshaft in the correct position. Note: Do not use excessive force to install Tooling (B). Do not use Tooling (B) to hold the crankshaft during repairs.
Check the rocker arms for an engine valve lash. There should be no engine valve lash.
Illustration 3 g02333215
Typical example
One electronic unit injector is not shown for clarity.
If there is an engine valve lash at any position the engine valve lash may be caused by a normal leakdown