Engine Mechanical - 8.1L V8: Other Chevrolet Silverado 1500 HD

FUEL PRESSURE RELEASE

Fuel Pressure Release Procedure

1. Disconnect negative battery cable.
2. Remove fuel injector sight shield.
3. Loosen fuel filler cap in order to relieve fuel tank vapor pressure.
4. Connect Fuel Pressure Gauge (J-34730-1A) to fuel pressure valve. Wrap a shop towel around the fitting while connecting gauge in order to avoid spillage.
5. Install gauge bleed hose into an approved container.
6. Open valve on the gauge to bleed system pressure. The fuel connections are now safe for servicing.
7. Drain any fuel remaining in the fuel pressure gauge into an approved container.

COOLING SYSTEM BLEEDING

Note. When adding coolant, use DEX-COOL® coolant. If silicated coolant is added to system, premature engine, heater core or radiator corrosion may result. In addition, engine coolant will require change sooner, at 30,000 miles or 24 months.

INTAKE MANIFOLD

Note. The intake manifold, throttle body, fuel rail, and injectors may be removed as an assembly. If not servicing the individual components, remove manifold as a complete assembly. (Схема №1)

OIL PAN

Note. Do not raise engine by crankshaft balancer to perform this service procedure. Damage to crankshaft balancer or crankshaft may occur.

Cylinder Head Cleaning Procedure

1. Clean valve stems and heads on a buffing wheel.
2. Clean valve stem keys, valve spring cap, valve spring, valve rotators, valve and cylinder head with solvent.
3. Dry components with compressed air.
4. Use Carbon Removal Brush (J-8089) in order to clean carbon from combustion chambers.

Flatness Measurement Procedure

1. Measure cylinder head for warpage with a straight edge and feeler gauge. A cylinder head block deck with warpage in excess of 0.002" (0.050 mm) within a 6.0" (150.0 mm) area must be repaired or replaced. A cylinder head intake manifold deck with warpage in excess of 0.003" (0.080 mm) must be repaired or replaced. See «ENGINE BLOCK (PRODUCTION SPECIFICATIONS)»(ref-158643-S40504407112004042200000) table.
2. See «CYLINDER HEAD»(ref-158643-S20026349752004042200000) table, for resurfacing specifications.
3. A cylinder head that requires excessive resurfacing must be replaced.

Valve Guide Measurement Procedure

1. Measure valve stem-to-guide clearance. Clamp Dial Indicator on to the exhaust port side of the cylinder head. Locate the indicator so that the movement of the valve stem from side to side, crosswise to the cylinder head, will cause a direct movement of the indicator stem. Drop the valve head about 0.064" (1.6 mm) off the valve seat. Use light pressure when moving the valve stem from side to side in order to obtain a clearance reading. See «VALVES»(ref-158643-S31580385552004042200000) .
2. Valve guide with excessive clearance must be repaired. See «VALVE GUIDE REAMING PROCEDURE FOR OVERSIZED VALVE STEMS»(ref-158643-S29848874012004042200000) .
3. Replace cylinder head if valve guide cannot be repaired or reamed to accept an oversize valve stem.

Valve Guide Reaming Procedure For Oversized Valve Stems

1. Ream valve guide as necessary to achieve proper valve stem-to-guide clearance with the new, oversized valve stems.
2. Always recondition the valve seat after reaming valve guide bores or installing new valves.
3. Replace cylinder head if valve guide cannot be repaired or reamed to accept an oversize valve stem.

Valve Reconditioning Procedure

1. Replace valve if valve stem shows excessive wear or is warped.
2. Reface pitted valves on a valve refacing machine in order to insure the correct relationship between the head and stem.
3. Replace valve if the edge of the head is less than 0.031" (0.79 mm) thick after grinding.

Valve Seat Reconditioning Procedure

1. Recondition valve seats.
2. The valves must seat perfectly for the engine to deliver optimum power and performance.
3. Ensure that valve seat and valve are not shrouded after valve seat reconditioning. Adequate flow past the valve seat and valve is essential for cooling the valve head and valve seat area.
4. Correct contact between each valve and its seat in the cylinder head is also essential to ensure that the heat in the valve head is properly carried away.
5. The valve seats should be concentric to within 0.002" (0.050 mm) total indicator runout.

Cylinder Boring

1. Before you use any type of boring bar, clean the top of the cylinder block in order to remove any dirt or burrs.
2. Carefully follow the instructions furnished by the manufacturer regarding use of equipment.
3. When you rebore cylinders, make sure all crankshaft bearing caps are in place. Tighten the bearing caps to the proper torque in order to avoid distortion of the bores in the final assembly. The crankshaft must be removed prior to cylinder boring.
4. When you take the final cut with a boring bar, leave 0.001" (0.03 mm) on the diameter for finish honing. This gives the required position to the cylinder clearance specifications. (Carefully perform the honing and boring operation in order to maintain the specified clearances between pistons, rings, and cylinder bores).

Cylinder Honing

1. When honing the cylinders, follow the manufacturer's recommendations for equipment use, cleaning, and lubrication. Use only clean, sharp stones of the proper grade for the amount of material you remove. Dull, dirty stones cut unevenly and generate excessive heat. Do not hone to a final grade with a coarse or medium-grade stone. Leave sufficient metal so that all stone marks may be removed with fine grade stones. The re-honed surface finish should be 10-20 micro inch (0.25-0.50 micrometer). Perform final honing with a fine-grade stone and hone the cylinder in a cross hatch pattern at 20 to 30 degrees to obtain the proper clearance.
2. During the honing operation, thoroughly clean the cylinder bore. Repeatedly check the cylinder bore for fit with the selected oversized piston. All measurements of the cylinder bore should be made with the components at normal room temperature.
3. To eliminate taper in the cylinder, when honing, make full strokes of the hone in the cylinder. Repeatedly check the measurement at the top, the middle, and the bottom of the bore. The finish marks should be clean but not sharp. The finish marks should be free from embedded particles and torn or folded metal.
4. When finished, the reconditioned cylinder bores should have less than or meet the specified out-of-round or taper requirements.
5. After final honing and before the piston is checked for fit, clean the bores with hot water and detergent. Scrub the bores with a stiff bristle brush and rinse the bores thoroughly with hot water. Do not allow any abrasive material to remain in the cylinder bores. Abrasive material may cause premature wear of new piston rings and cylinder bores. Abrasive material will contaminate the engine oil and may cause premature wear of the bearings. After washing the cylinder bore, dry the bore with a clean shop towel.
6. Perform final measurements of the cylinder bore.
7. Permanently mark the piston for the specific cylinder to which it has been fitted.
8. Apply clean engine oil to each cylinder bore in order to prevent rusting.

Crankshaft & Connecting Rod Bearing Clearance Measurement

The crankshaft and connecting rod bearings are of the precision insert type and do not use shims for adjustment. Crankshafts with journals that measure less than minimum specifications must be replaced.

Micrometer Method For Crankshaft Bearings

1. Measure the crankshaft main journal diameter with a micrometer in several places along the length approximately 90 degrees apart, minimum of 4 places, and average the measurements.
2. Determine taper and the out-of-round. See «CRANKSHAFT»(ref-158643-S30011148722004042200000) table.
3. Install NEW crankshaft bearings into crankshaft bearing caps and engine block.
4. Install crankshaft bearing caps and crankshaft bearing cap bolts and studs. Tighten crankshaft bearing cap inner bolts to specification. See «TORQUE SPECIFICATIONS»(ref-158643-S34537563902004042200000) . Tighten the crankshaft bearing cap outer studs to specification. Using a Torque Angle Meter (J-36660-A) , tighten crankshaft bearing cap inner bolts an additional 90 degrees. Using the torque angle meter, tighten the crankshaft bearing cap outer studs an additional 80 degrees.
5. Measure crankshaft bearing Inside Diameter (ID) using an inside micrometer. Measure at a minimum of 4 places and average the measurements.
6. In order to determine the crankshaft bearing clearance, subtract the crankshaft journal diameter from the crankshaft bearing ID.
7. Compare crankshaft bearing clearance to specifications. See «CRANKSHAFT»(ref-158643-S30011148722004042200000) table.
8. If crankshaft bearing clearances exceeds specifications, install undersize crankshaft bearings to achieve the correct clearance.
9. Measure new crankshaft bearing inside diameter using an inside micrometer.
10. Replace crankshaft if the proper clearances cannot be obtained with standard size bearings.

Micrometer Method For Connecting Rod Bearings

1. Measure crank pin diameter with a micrometer in several places along the length, approximately 90 degrees apart, minimum of 4 places, and average the measurements.
2. Determine the taper and the out-of-round. See «CRANKSHAFT»(ref-158643-S30011148722004042200000) table.
3. Install NEW connecting rod bearings into the connecting rod cap and the connecting rod.
4. Install connecting rod cap and the original, used, nuts. Tighten the connecting rod nuts to specification. See «TORQUE SPECIFICATIONS»(ref-158643-S34537563902004042200000) . Tighten the connecting rod nuts an additional 90 degrees.
5. Measure connecting rod bearing Inside Diameter (ID) using an inside micrometer.
6. Compare the connecting rod bearing clearance specifications. See «CRANKSHAFT»(ref-158643-S30011148722004042200000) table.
7. If the connecting rod bearing clearances exceed specifications, replace components as required.

Measuring Crankshaft Bearing Clearance Using Plastigage®

1. Install the crankshaft and the new crankshaft bearings into the block, making sure not to damage the reluctor rings of the crankshaft.
2. Install gaging plastic the full width of the crankshaft journal.
3. Install crankshaft bearing caps and the crankshaft bearing cap bolts and studs. Tighten the crankshaft bearing cap inner bolts to specification. See «TORQUE SPECIFICATIONS»(ref-158643-S34537563902004042200000) . Tighten the crankshaft bearing cap outer studs to specification. Using a Torque Angle Meter, tighten the crankshaft bearing cap inner bolts an additional 90 degrees. Using torque angle meter, tighten the crankshaft bearing cap outer studs an additional 80 degrees.
4. Remove crankshaft bearing cap bolts and the crankshaft bearing caps. The gaging plastic may adhere to either the crankshaft journal or the crankshaft bearing surfaces.
5. On the edge of the gaging plastic envelope there is a graduated scale. Without removing the gaging plastic, measure the compressed width at the widest point.
6. If the flattened gaging plastic tapers toward the middle or the ends, there may be a difference in clearance indicating taper, low spot or other irregularity of the crankshaft bearing or the crankshaft journal. Normally the crankshaft journals wear evenly and are not out-of-round. However, if a crankshaft bearing is being fitted to an out-of-round crankshaft journal, see «CRANKSHAFT»(ref-158643-S30011148722004042200000) table, be sure to fit to the maximum diameter of the crankshaft journal. If the crankshaft bearing is fitted to the minimum diameter and the crankshaft journal is excessively out-of-round, the interference between the crankshaft bearing and the crankshaft journal will result in rapid crankshaft bearing failure.
7. Compare the crankshaft bearing clearance to the specifications. See «CRANKSHAFT»(ref-158643-S30011148722004042200000) table.
8. If crankshaft bearing clearances exceeds specifications, replace components as required.
9. Measure new crankshaft bearing inside diameter using the same method.
10. Replace crankshaft if the proper clearances cannot be obtained with standard size bearings.
11. Remove flattened gaging plastic.
12. Measure remaining crankshaft journals.

Measuring Connecting Rod Bearing Clearance Using Plastigage®

1. Install connecting rod bearings into the connecting rod and the connecting rod cap.
2. Using rubber fuel line over the connecting rod bolts, install piston and connecting rod assembly onto crank pin journal.
3. Install gaging plastic the full width of the crank pin journal.
4. Install connecting rod cap and original, used, nuts. Tighten connecting rod nuts to specification. See «TORQUE SPECIFICATIONS»(ref-158643-S34537563902004042200000) . Tighten connecting rod nuts an additional 90 degrees.
5. Remove connecting rod nuts and cap. The gaging plastic may adhere to either the crank pin journal or connecting rod bearing surface.
6. On the edge of the gaging plastic envelope there is a graduated scale. Without removing the gaging plastic, measure the compressed width at the widest point. If the flattened gaging plastic tapers toward the middle or the ends, there may be a difference in clearance indicating taper, low spot or other irregularity of the crankshaft bearing or the crank pin journal.
7. Normally the crank pin journals wear evenly and are not out-of-round. However, if a connecting rod bearing is being fitted to an out-of-round crank pin journal, see «CRANKSHAFT»(ref-158643-S30011148722004042200000) table. Be sure to fit to the maximum diameter of the crank pin journal. If the connecting rod bearing is fitted to the minimum diameter and the crank pin journal is excessively out-of-round, the interference between the connecting rod bearing and the crank pin journal will result in rapid connecting rod bearing failure
8. Compare connecting rod bearing clearance to specifications. See «CRANKSHAFT»(ref-158643-S30011148722004042200000) table.
9. If connecting rod bearing clearances exceed specifications, replace components as required.
10. Remove flattened gaging plastic.
11. Measure remaining crank pin journals.

Measuring Crankshaft End Play

1. Install the Magnetic Base Dial Indicator, or equivalent to the cylinder block, with the dial indicator plunger against one of the counterweights of the crankshaft.
2. Firmly thrust the end of the crankshaft first rearward then forward. This will line up the rear crankshaft bearing and the crankshaft thrust surfaces.
3. With crankshaft pushed forward, zero the dial indicator. Move crankshaft rearward and read the end play measurement on the dial indicator. An optional method is to insert a feeler gauge between the crankshaft and bearing surface and measure clearance. See «CRANKSHAFT»(ref-158643-S30011148722004042200000) table.
4. If the correct end play cannot be obtained, inspect crankshaft thrust wall surface or surfaces for wear and/or excessive runout.
5. Inspect crankshaft for binding. Turn crankshaft to check for binding. If crankshaft does not turn freely, loosen crankshaft bearing bolts and studs, one cap at a time, until the tight bearing is located. The following condition or conditions could cause a lack of clearance at the bearing: Burrs on crankshaft bearing cap. Foreign matter between crankshaft bearing and block or crankshaft bearing cap. A faulty crankshaft bearing.

Measuring Connecting Rod Side Bearing

1. Install the Magnetic Based Dial Indicator, or equivalent to the cylinder block, with the dial indicator plunger against the side of the pair of connecting rods.
2. With connecting rods pushed forward, zero the dial indicator. Firmly move the pair of connecting rods side to side and read the measurement on dial indicator. An optional method is to insert a feeler gauge between the connecting rod caps and measure connecting rod side clearance. See «CRANKSHAFT»(ref-158643-S30011148722004042200000) table.