Parts
PartValve Lifters
ManufacturerCHY
OEM part #53021894AA
Price$23.25
Labor
Replace — Both Banks4.0 hr
Left Bank2.6 hr
Right Bank2.6 hr
Lifter / Lash Adjuster: Testing and Inspection
- Engine oil level too high or too low. This may cause aerated oil to enter the adjusters and cause them to be spongy.
- Insufficient running time after rebuilding cylinder head. Low speed running up to 1 hour may be required.
- Turn engine off and let set for a few minutes before restarting. Repeat this several times after engine has reached normal operating temperature.
- Low oil pressure.
- The oil restrictor in cylinder head gasket or the oil passage to the cylinder head is plugged with debris.
- Air ingested into oil due to broken or cracked oil pump pick up.
- Worn valve guides.
- Rocker arm ears contacting valve spring retainer.
- Rocker arm loose, adjuster stuck or at maximum extension and still leaves lash in the system.
- Oil leak or excessive cam bore wear in cylinder head.
- Faulty lash adjuster. -Check lash adjusters for sponginess while installed in cylinder head and cam on camshaft at base circle. Depress part of rocker arm over adjuster. Normal adjusters should feel firm when pressed quickly. When pressed very slowly, lash adjusters should collapse. -Remove suspected lash adjusters, and replace. -Before installation, make sure adjusters are full of oil. This can be verified by little plunger travel when lash adjuster is depressed quickly.
Factory service manual
From the 2008 KK factory manual — descriptions, specs, torque & procedures for this part.
HYDRAULIC LASH ADJUSTER
A tappet-like noise may be produced from several items. Check the following items.
1. Engine oil level too high or too low. This may cause aerated oil to enter the adjusters and cause them to be spongy. 2. Insufficient running time after rebuilding cylinder head. Low speed running up to 1 hour may be required. 3. Turn engine off and let set for a few minutes before restarting. Repeat this several times after engine has reached normal operating temperature. 4. Low oil pressure. 5. The oil restrictor in cylinder head gasket or the oil passage to the cylinder head is plugged with debris. 6. Air ingested into oil due to broken or cracked oil pump pick up. 7. Worn valve guides. 8. Rocker arm ears contacting valve spring retainer.
9. Rocker arm loose, adjuster stuck or at maximum extension and still leaves lash in the system. 10. Oil leak or excessive cam bore wear in cylinder head. 11. Faulty lash adjuster. Check lash adjusters for sponginess while installed in cylinder head and cam on camshaft at base circle. Depress part of rocker arm over adjuster. Normal adjusters should feel firm when pressed quickly. When pressed very slowly, lash adjusters should collapse. Remove suspected lash adjusters, and replace. Before installation, make sure adjusters are full of oil. This can be verified by little plunger travel when lash adjuster is depressed quickly.
Removal
1 - TIMING CHAIN COVER 2 - CRANKSHAFT TIMING MARKS
1
Disconnect the negative cable from the battery.
2
Raise the vehicle on a hoist.
3
Disconnect the exhaust pipe at the left side exhaust manifold.
4
Drain the engine coolant. Refer to COOLING .
5
Lower the vehicle.
6
Remove the intake manifold. Refer to appropriate procedure.
7
Remove the cylinder head cover. Refer to appropriate procedure.
8
Remove the fan shroud and fan blade assembly. Refer to COOLING .
9
Remove accessory drive belt. Refer to COOLING .
10
Remove the power steering pump and set aside.
11
Rotate the crankshaft until the damper timing mark is aligned with TDC indicator mark (2). See Fig. 48.
1 - LEFT CYLINDER HEAD 2 - RIGHT CYLINDER HEAD
12
Verify the V6 mark on the camshaft sprocket is at the 12 o'clock position. See Fig. 49. Rotate the
crankshaft one turn if necessary.
13
Remove the crankshaft damper. See REMOVAL.
14
Remove the timing chain cover. See REMOVAL.
1 - SPECIAL TOOL 8429 2 - CAMSHAFT CHAIN 3 - CRANKSHAFT TIMING GEAR
15
Lock the secondary timing chains to the idler sprocket using Secondary Camshaft Chain Holder 8429 (1).
See Fig. 50.
NOTE
Mark the secondary timing chain prior to removal to aid in installation.16
Mark the secondary timing chain, one link on each side of the V6 mark on the camshaft drive gear.
17
Remove the left side secondary chain tensioner.
1 - RIGHT CYLINDER HEAD ACCESS PLUG 2 - LEFT CYLINDER HEAD ACCESS PLUG
18
Remove the cylinder head access plug (1) (2). See Fig. 51.
19
Remove the left side secondary chain guide.
20
Remove the retaining bolt and the camshaft drive gear.
CAUTION
Do not allow the engine to rotate. Severe damage to the valve train can occur.CAUTION
Do not overlook the four smaller bolts at the front of the cylinder head. Do not attempt to remove the cylinder head without removing these four bolts.NOTE
The cylinder head is attached to the cylinder block with twelve bolts.21
Remove the cylinder head retaining bolts.
22
Remove the cylinder head and gasket. Discard the gasket.
CAUTION
Do not lay the cylinder head on its gasket sealing surface, due to the design of the cylinder head gasket any distortion to the cylinder head sealing surface may prevent the gasket from properly sealing resulting in leaks.
HYDRAULIC LASH ADJUSTER
A tappet-like noise may be produced from several items. Check the following items.
1. Engine oil level too high or too low. This may cause aerated oil to enter the adjusters and cause them to be spongy. 2. Insufficient running time after rebuilding cylinder head. Low speed running up to 1 hour may be required. 3. Turn engine off and let set for a few minutes before restarting. Repeat this several times after engine has reached normal operating temperature. 4. Low oil pressure. 5. The oil restrictor in cylinder head gasket or the oil passage to the cylinder head is plugged with debris. 6. Air ingested into oil due to broken or cracked oil pump pick up. 7. Worn valve guides. 8. Rocker arm ears contacting valve spring retainer. 9. Rocker arm loose, adjuster stuck or at maximum extension and still leaves lash in the system. 10. Oil leak or excessive cam bore wear in cylinder head. 11. Faulty lash adjuster. Check lash adjusters for sponginess while installed in cylinder head and cam on camshaft at base circle. Depress part of rocker arm over adjuster. Normal adjusters should feel very firm. Spongy
adjusters can be bottomed out easily. Remove suspected lash adjusters, and replace. Before installation, make sure adjusters are at least partially full of oil. This can be verified by little or no plunger travel when lash adjuster is depressed.