Cleaning and Inspection Procedure - Conditional

WARNING: This page is about a different variant/trim than selected.

NOTE:

The following cleaning and inspection and/or overhaul steps are ONLY to be performed as determined necessary based on the condition of the part being removed with the intention of reinstallation. The labor time to perform any of these steps is not included in the base labor time and if required would need to be documented and submitted as Other Labor Hours for warranty claim reimbursement. A description of the repairs performed must be documented in the technician correction comments.

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WARNING:
Refer to Safety Glasses and Compressed Air Warning

Clean the connecting rods (1) in solvent and dry with compressed air.
Inspect the connecting rod (1) for the following:
1. Signs of being twisted, bent, nicked or cracked
2. Scratches or abrasion on the connecting rod (1) bearing seating surfaces
If the connecting rod bores (2) contain minor scratches or abrasions, clean the bores in a circular direction with a light emery paper. DO NOT scrape the connecting rod (1) or connecting rod cap.
If the beam of the connecting rod (1) is scratched or has other damage replace the connecting rod.
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Clean the piston with a cleaning solvent. Do NOT wire brush any parts of the piston.
Clean the piston ring grooves.
Inspect the piston on the following:
1. Cracked ring lands, skirts or pin bosses
2. Ring grooves for nicks
3. Eroded areas on the top of the piston (1)
4. Scored or damaged skirts (2)
5. Worn piston pin bores (3)
If there is any excessive wear, replace the piston.
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Measure the clearance between the piston pin (1) and the piston bore. Use the following procedure:
1. Measure the piston pin outside diameter (a).
2. Measure the piston bore diameter (b).
3. Substract the piston pin outside diameter (a) from the piston bore diameter (b) to calculate the clearance.
4. For the correct value of the clearance piston pin (1) in the piston (2). Engine Mechanical Specifications
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Inspect the connecting rod piston pin bore for any signs of pitting or erosion. If any pitting or erosion is present replace the connecting rod.
Measure the clearance between the piston pin (1) and the connecting rod bore. Use the following procedure:
1. Measure the piston pin outside diameter (a).
2. Measure the connecting rod bore diameter (b).
3. Substract the piston pin outside diameter (a) from the connecting rod diameter (b) to calculate the clearance.
4. For the correct value of the clearance piston pin (1) in the connecting rod (2). Engine Mechanical Specifications
If there is excessive clearance, replace the piston pin (1) and repeat the measurements.
If there is still excessive clearance, replace the connecting rod (2).
If there is excessive clearance, replace the piston pin (1) and repeat the measurements.
If there is still excessive clearance, replace the piston.
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Install each piston ring to the cylinder (1) and measure the piston ring end gap at the points mentioned in the step below.
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Measure piston ring end gap at point a:
1. The piston compression upper ring end gap. Place the piston ring in the area of the bore where the piston ring will travel, approximately 10 mm (0.394 in) down from the deck surface. Engine Mechanical Specifications
2. The piston compression lower ring end gap. Place the piston ring in the area of the bore where the piston ring will travel, approximately 10 mm (0.394 in) down from the deck surface. Engine Mechanical Specifications
3. The piston oil ring rail end gap. Place the piston ring in the area of the bore where the piston ring will travel, approximately 10 mm (0.394 in) down from the deck surface. Engine Mechanical Specifications
Measure piston ring end gap at point b:
1. The piston compression upper ring end gap. Place the piston ring in the area of the bore where the piston ring will travel, approximately 42 mm (1.654 in) down from the deck surface. Engine Mechanical Specifications
2. The piston compression lower ring end gap. Place the piston ring in the area of the bore where the piston ring will travel, approximately 42 mm (1.654 in) down from the deck surface. Engine Mechanical Specifications
3. The piston oil ring rail end gap. Place the piston ring in the area of the bore where the piston ring will travel, approximately 42 mm (1.654 in) down from the deck surface. Engine Mechanical Specifications
Measure piston ring end gap at point c:
1. The piston compression upper ring end gap. Place the piston ring in the area of the bore where the piston ring will travel, approximately 140 mm (5.512 in) down from the deck surface. Engine Mechanical Specifications
2. The piston compression lower ring end gap. Place the piston ring in the area of the bore where the piston ring will travel, approximately 140 mm (5.512 in) down from the deck surface. Engine Mechanical Specifications
3. The piston oil ring rail end gap. Place the piston ring in the area of the bore where the piston ring will travel, approximately 140 mm (5.512 in) down from the deck surface. Engine Mechanical Specifications
If the clearance is greater than the provided specifications, the piston rings must be replaced.
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Measure the piston ring axial clearance (1). Compare the measurements with those provided below:
1. The piston compression upper ring clearance. For the correct value of the clearance. Engine Mechanical Specifications
2. The piston compression lower ring clearance. For the correct value of the clearance. Engine Mechanical Specifications
3. The piston oil ring rail clearance. For the correct value of the clearance. Engine Mechanical Specifications
If the clearance is greater than the provided specifications, replace the piston rings and repeat the measurements.
If the clearance is still greater than the provided specifications, replace the pistons.
Measure the engine cylinder bore. Engine Block Overhaul
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Using a micrometer (2) or caliper at a right angle to the piston, measure the width of the piston (1) at 3 different measuring points from the bottom of the skirt.
1. First measure point 13 mm (0.512 in) from the bottom of the skirt.
2. Second measure point 38 mm (1.496 in) from the bottom of the skirt.
3. Third measure point 68.2 mm (2.685 in) from the bottom of the skirt.
Subtract the piston (1) diameter from the cylinder bore diameter in order to calculate the piston-to-bore clearance.
For the correct value of the clearance piston to bore. Engine Mechanical Specifications
If the clearance obtained through measurement is greater than these specifications and the cylinder bores are within the specification, replace the piston (1).
Install the connecting rod bearings and the connecting rod bearing caps.

CAUTION:

Refer to Fastener Caution .

CAUTION:

Refer to Torque-to-Yield Fastener Caution .

Connecting Rod Bolt - Install and tighten - Fastener Specifications
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Using an internal measuring device, measure the connecting rod bearing diameters at 3 different measuring points (1).
Calculate the average connecting rod inner diameter.
Formula: (1. result + 2. result + 3. result) / 3
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Using a micrometer gauge, measure the connecting rod journal diameter at 2 different measuring points between (1) and (3) and between (2) and (4).
Calculate the average connecting rod journal diameter.
Formula: (1. result + 2. result) / 2.
Subtract the average connecting rod journal diameter from the average connecting rod bearing diameter in order to determine the connecting rod bearing clearance.
For the correct value of the connecting rod bearing clearance. Engine Mechanical Specifications
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Clean the camshaft housing (1) in solvent.
Inspect the camshaft housing (1) for damage or cracking. A cracked or damaged camshaft housing may:
1. Leak engine oil
2. Affect crankcase ventilation
3. Interfere with the camshafts
4. Allow water or condensation to enter the engine
Inspect the exterior of the camshaft housing (1) for the following conditions:
1. Damage to the camshaft housing bolt holes (2)
2. Damage to the camshaft housing injector bracket bolt holes (3)
3. Damage to the positive crankcase ventilation valve (4).
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Inspect the interior of the camshaft housing for the following conditions:
1. Inspect the camshaft housing for cracks, casting imperfections, or damage.
2. Inspect the camshaft housing seal locations (2) for cracks or damage.
3. Inspect the crankcase ventilation oil separator cover (1) for cracks or damage.
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Clean all sealing surfaces.
Clean all threads if necessary.
Inspect the wastegate regulator mechanism (1) for functionality.
Inspect the turbine blades for damage or foreign material.
Inspect the turbine blade shaft for excessive radial and axial end play.
Inspect the compressor air intake turbocharger for cracks or other damage.
Inspect the compressor air intake turbocharger mating surface for flatness.
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Remove any old sealant or gasket material.
Clean all cylinder head surfaces with non-corrosive cleaning solvent.
Blow out all the oil galleries using compressed air.
Remove any carbon deposits from the combustion chamber (2).
Inspect the cylinder head sealing surface for flatness using a straightedge (1). If the cylinder head sealing surface is uneven, replace the cylinder head. Do NOT machine the cylinder head.
Inspect all the threaded holes for damage. Threads may be reconditioned with thread inserts.
Inspect the cylinder head camshaft bearing surfaces for the following conditions:
1. Excessive scoring or pitting.
2. Discoloration from overheating.
3. Deformation from excessive wear.
If any of the above conditions exist on the camshaft bearing surfaces, replace the cylinder head.
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Inspect the cylinder head (1) for the following:
1. Cracks, damage, or pitting in the combustion chambers.
2. Debris in the oil galleries, continue to clean the galleries until all debris is removed.
3. Coolant leaks or damage to the deck face sealing surface, if coolant leaks are present, measure the surface warpage as described under cylinder head measurement deck flatness inspection.
4. Damage to any gasket surfaces.
5. Burnt or eroded areas in the combustion chamber.
6. Cracks in the exhaust ports (3) and combustion chambers.
7. External cracks in the water passages.
8. Restrictions in the intake or exhaust ports (3).
9. Restrictions in the cooling system passages.
10. Rusted, damaged or leaking core plugs.
Inspect the exterior of the camshaft housing ladder frame (2) for the following conditions:
1. Damage to the camshaft housing ladder frame (4) bolt holes.
2. Damage to the injector bore holes.
3. Damage to the oil passages.
Inspect the interior of the camshaft housing ladder frame (2) for the following conditions:
1. Inspect the camshaft housing ladder frame (2), casting imperfections, cracks or damage.
2. Inspect the camshaft housing ladder frame (2) seal locations (1) for cracks or damage.
If the cylinder head (1) or ladder frame (2) is cracked or damaged, they must be replaced. No welding or patching of the is allowed.
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Clean the exhaust gas recirculation valve (1).
Inspect the exhaust gas recirculation valve (1).
Replace the exhaust gas recirculation valve (1) if any damage is found.
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Clean the exhaust manifold (1) in solvent.

WARNING:

Refer to Safety Glasses and Compressed Air Warning

Dry the exhaust manifold (1) with compressed air.
Inspect the exhaust manifold (1) for damage.
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Using a straightedge (2) and a feeler gauge, measure the exhaust manifold mounting face (3) for warpage. An exhaust manifold face with warpage in excess of 0.2 mm (0.008 in) may cause an exhaust leak and may effect diagnostics and system performance.
An exhaust manifold (1) which does not fall within the specifications must be replaced.
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CAUTION:
The fuel injector must be cleaned with the proper cleaning equipment. DO NOT use abrasive cleaning methods, such as a metallic brush, to remove deposits. Cleaning an injector with improper tools will damage the fuel injector.

Using a soft bristle non-metallic brush and top engine cleaner, remove any deposits from the high pressure diesel fuel injector nozzle tip (1) and the copper washer sealing area before installation.
Inspect the high pressure diesel fuel injector nozzle tip (1) for cracks, dents, or other damage.
Inspect the high pressure diesel fuel injector nozzle tip (1) for any signs of discoloration.
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Clean the intake manifold mating surfaces.
Inspect the intake manifold (1) for damage.
Inspect the intake manifold (1) for cracks and fractures.
Inspect all 12 intake runner valves (5) for damage.
Clean the throttle body sealing surface (3).
Clean the exhaust gas recirculation cooler outlet pipe sealing surface (2).
Clean the intake manifold to cylinder head sealing surface (4).
Replace the intake manifold (1) as necessary.
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Visually inspect the intake manifold mounting face (1) for cracks, warpage, or damage. If any damage is found replace the intake manifold. An intake manifold face with cracks, warpage or damage may cause an intake leak and may effect diagnostics and system performance.
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Clean the lower crankcase extension (1) in solvent.
Inspect all sealing and mating surfaces for damage, and repair or replace the lower crankcase extension (1) if necessary.
Inspect all threaded and through holes for damage or excessive debris.
Check for roughness or end play in the oil pump drive shaft bearing (1).
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Clean the oil pump (1) sealing surfaces with solvent.
Dry the oil pump (1) sealing surfaces.
Inspect the oil pump (1) sealing surfaces.
Rotate the oil pump drive shaft and check for roughness.
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Inspect the oil pump pipe tube (1) for cracks, imperfections, and/or damage.
Inspect the mounting surface (2) for possible leakage paths.
Inspect the oil pump screen (3) for blockage, foreign material, tears, cracks and/or damage.
Clean the oil pump suction pipe with solvent.
Clean the oil pump suction pipe mating surfaces.