Engine Mechanical - 5.3L: Overhaul Chevrolet TrailBlazer I

Piston and Connecting Rod Disassemble

Tools Required

J 24086-C Piston Pin Remover/Installer Set

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1. Using piston ring pliers, remove the piston rings from the piston.
2. Install fork insert J 24086-920A into fixture J 24086-10.
3. Install the piston and connecting rod assembly onto J 24086-10.
4. Install J 24086-107 into the piston pin and J 24086-88A through the fixture and into J 24086-107. NOTE: After the installer hub bottoms on the support assembly, do not exceed 35 000 kPa (5,000 psi) pressure, this could cause damage to the tool.
5. Press the piston pin from the piston and connecting rod assembly.
6. The piston and pin are a matched set and are not to be serviced separately. Mark, sort, or organize the piston and the matching piston pin. Refer to «SEPARATING PARTS»(ref-188498-S17158006432005090700000) .

Piston and Connecting Rod Assemble

Tools Required

J 24086-C Piston Pin Remover/Installer Set

The piston and connecting rod MUST be assembled properly.

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1. Install fork insert J 24086-920 into fixture J 24086-10 . CAUTION: Avoid contact with HOT components. Wear safety glasses and protective gloves to avoid personal injury. NOTE: Applying excessive heat to the connecting rod may damage or distort the rod. Rod temperature SHOULD NOT exceed 315°C (600°F). At this temperature the end of the connecting rod will turn a straw color upon visual inspection.
2. Use a torch and apply MILD heat to the pin end of the connecting rod. Mild heating of the connecting rod will ease in piston and pin assembly.
3. With the piston and connecting rod properly assembled, both the flat flange area of the connecting rod and the alignment mark on the top of the piston will be facing the front of the engine.
4. Assemble the piston, connecting rod and adapter J 24086-16A and install onto fixture J 24086-10 .
5. Adjust installation pin J 24086-9 to I-8. NOTE: After the installer hub bottoms on the support assembly, do not exceed 35 000 kPa (5,000 psi) pressure, this could cause damage to the tool.
6. Insert pin J 24086-9 through fixture J 24086-10 and to the piston pin.
7. Press pin J 24086-9 until the installer bottoms on fixture J 24086-10 .
8. Measure the piston (1), pin (3), and connecting rod (2) for proper assembly. 8.1. Place the piston and connecting rod assembly onto a table or other flat surface. Lay the flat top of the piston (1) onto the table surface. 8.2. Slide the connecting rod (2) and pin (3) to one side and hold firmly against the inside of the piston (1). 8.3. Measure the pin (3) for proper installation. A properly installed piston pin should protrude 1.27 mm (0.05 in) from the side of the piston. IMPORTANT: When installing the piston rings onto the piston, use a ring expanding plier type tool. Do not roll the piston rings into the grooves of the piston. Use caution and care to expand the piston rings only slightly larger than the outside diameter (OD) of the piston.
9. Using piston ring pliers, install the piston rings onto the piston. 9.1. Install the oil control ring spacer in the groove. 9.2. Install the lower oil control ring. The oil control rings do not have a dimple or orientation mark and may be installed in either direction. 9.3. Install the upper oil control ring. 9.4. Stagger the three oil control ring end gaps a minimum of 90 degrees. 9.5. Using piston ring pliers, install the lower compression ring. The lower compression ring has a dimple or orientation mark and must face the top of the piston. 9.6. Using piston ring pliers, install the upper compression ring. The upper compression ring does not have a dimple or orientation mark and may be installed in either direction. 9.7. Stagger the compression ring end gaps a minimum of 25 mm (1.0 in).

Cylinder Head Disassemble

Tools Required

J 8062 Valve Spring Compressor-Head Off

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1. Remove the spark plugs from the cylinder heads.
2. Use the J 8062 in order to compress the valve spring.
3. Remove the valve stem keys (2).
4. Remove the valve spring cap (3).
5. Remove the valve spring (4).
6. Remove the valves (9 and 10).
7. Remove the valve stem oil seal and shim assembly (5). Refer to «SEPARATING PARTS»(ref-188498-S17158006432005090700000) .
8. Remove the cylinder head expansion plugs (1), if required.
9. Remove the coolant sensor from the left cylinder head, if required.
10. Remove the coolant plug from the right cylinder head, if required.

Cylinder Head Assemble

Tools Required

J 8062 Valve Spring Compressor

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1. Clean the cylinder head valve spring seat and/or shim area. IMPORTANT: When using the valves and related components again, install the parts to their original location.
2. Install the valves (9 and 10) into the proper guides. Refer to «SEPARATING PARTS»(ref-188498-S17158006432005090700000) . IMPORTANT: The valve stem oil seal alignment and position on the valve guide is critical. An improperly installed valve stem oil seal may lead to excessive oil consumption, increased vehicle emissions, or component damage.
3. Install the valve stem oil seal and shim assembly (5).
4. Install the valve spring (4).
5. Install the valve spring cap (3).
6. Compress the valve spring using the J 8062.
7. Install the valve stem keys. 7.1. Use grease to hold the keys in place and remove the J 8062. 7.2. Make sure the keys seat properly in the groove of the valve stem. 7.3. Tap the end to the valve stem with a plastic faced hammer to seat the keys, if necessary.
8. Measure the valve spring installed height using a ruler. Measure from the base of the spring to the top of the spring. If the installed height exceeds 46.25 mm (1.82 in), install a valve seat spring shim of approximately 0.5 mm (0.02 in) thick. Do not shim the valve spring to obtain less than the specified height. Do not assemble the components without a spring shim on the cylinder head, aluminum head.
9. Install the remaining valves, springs, and other components.
10. Install sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the threads of the coolant sensor. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) in Cautions and Notices.
11. Install the coolant sensor into the left cylinder head. Tighten Tighten the coolant sensor to 20 N.m (15 lb ft).
12. Install the coolant plug to the right cylinder head. Tighten Tighten the coolant plug to 20 N.m (15 lb ft).
13. Apply threadlock GM P/N 12345382 (Canadian P/N 10953489) or equivalent to the sides of the cylinder head expansion plugs (1), if applicable.
14. Install the expansion plugs into the cylinder head, aluminum head. A properly installed plug should be slightly below flush with the face of the head.

Oil Pump Disassemble

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1. Remove the oil pump cover bolts.
2. Remove the oil pump cover. IMPORTANT: Mark or identify the gears for assembly. Refer to «SEPARATING PARTS»(ref-188498-S17158006432005090700000) .
3. Remove the drive gear.
4. Remove the driven gear.
5. Remove the pressure relief valve plug.
6. Remove the pressure relief valve spring.
7. Remove the pressure relief valve.
8. Inspect the oil pump components. Refer to «OIL PUMP CLEANING AND INSPECTION»(ref-188498-S15314593702005090700000) .

Oil Pump Assemble

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1. Install the driven gear into the pump housing. Install the driven gear with the orientation mark facing the pump cover.
2. Install the drive gear into the pump housing.
3. Install the oil pump cover. NOTE: Refer to «FASTENER NOTICE»(ref-175132-S17785009232005041500000) in Cautions and Notices.
4. Install the pump cover bolts. Tighten Tighten the oil pump cover bolts to 12 N.m (106 lb in).
5. Install the regulator valve.
6. Install a NEW regulator valve spring.
7. Install the pressure relief valve plug. Tighten Tighten the pressure relief valve plug to 12 N.m (106 lb in).
8. Inspect the oil pump for smoothness of operation by rotating the drive gear.

Service Prior to Assembly

1. Dirt or debris will cause premature wear of the rebuilt engine. Clean all the components. Refer to «CLEANLINESS AND CARE»(ref-188498-S37974590412005090700000) .
2. Use the proper tools to measure components when inspecting for excessive wear. Components that are not within the manufacturers specifications must be repaired or replaced.
3. When the components are installed into an engine, return the components to their original location, position and direction. Refer to «SEPARATING PARTS»(ref-188498-S17158006432005090700000) .
4. During assembly, lubricate all the moving parts with clean engine oil. This will provide initial lubrication when the engine is first started.

Piston and Connecting Rod Assembly

The pistons are cast aluminum. The pistons use two compression rings and one oil control ring assembly. The piston is a low friction, lightweight design with a flat or recessed top and barrel shaped skirt. The piston pins are chromium steel, have floating fit in the piston, and are retained by a press fit in the connecting rod. The connecting rods are powdered metal. The connecting rods are fractured at the connecting rod journal and then machined for the proper clearance. 2003 applications use a piston with a graphite coated skirt.

Valve Rocker Arm Cover Assemblies

The valve rocker arm covers are cast aluminum and use a pre-molded silicon gasket for sealing. Mounted to each rocker cover are the coil and bracket assemblies. Incorporated into the covers are the oil fill tube, the positive crankcase ventilation (PCV) system passages, and the engine fresh air passages.

Assembling Components

Note. Refer to SEALANT NOTICE in Cautions and Notices.

1. When assembling components, use only the sealant specified or equivalent in the service procedure.
2. Sealing surfaces should be clean and free of debris or oil.
3. Specific components such as crankshaft oil seals or valve stem oil seals may require lubrication during assembly.
4. Components requiring lubrication will be identified in the service procedure.
5. When applying sealant to a component, apply the amount specified in the service procedure.
6. Tighten bolts to specifications. Do not overtighten.