Hummer H2. Manual — part 1808

Fig. 414: Piston & Connecting Rod Components
Courtesy of GENERAL MOTORS CORP.

IMPORTANT:

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Replace pistons, pins, and connecting rods that are damaged or
show signs of excessive wear.

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The first design press-fit piston, pin, and connecting rod are to be
serviced as an assembly.

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Do not wire brush any part of the piston.

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Measurement of the components should be taken with the
components at normal room temperature.

2004 Hummer H2

2004 ENGINE Engine Mechanical - 4.8L, 5.3L, and 6.0L - Hummer H2

1. Clean the varnish and carbon from the piston (1) using cleaning solvent.

2. Dry the components with compressed air.

CAUTION: Wear safety glasses in order to avoid eye damage.

2004 Hummer H2

2004 ENGINE Engine Mechanical - 4.8L, 5.3L, and 6.0L - Hummer H2

Fig. 415: Cleaning Piston Ring Grooves
Courtesy of GENERAL MOTORS CORP.

3. Clean the piston ring grooves with a suitable ring groove cleaning tool.

4. Clean the oil lubrication holes and slots.

2004 Hummer H2

2004 ENGINE Engine Mechanical - 4.8L, 5.3L, and 6.0L - Hummer H2

Fig. 416: Inspecting Piston For Damage
Courtesy of GENERAL MOTORS CORP.

5. Inspect the piston for the following conditions:

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Cracks in the piston ring lands, the piston skirt, or pin bosses

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Piston ring grooves for nicks, burrs, or warpage which may cause the piston ring to bind

MINOR imperfections may be removed from the piston with a fine file.

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Scuffed or damaged skirts (2)

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Eroded areas at the top of the piston (1)

2004 Hummer H2

2004 ENGINE Engine Mechanical - 4.8L, 5.3L, and 6.0L - Hummer H2