Engine - Tapping/Rattling Noises
No: 12/02/00/NAS
Ref: WSM Section 12
Overhaul Manual
Replaces TIB 12/01/98/NAS
Issue: 2
Date: 12/22/00
Rocker Arm Rattle/Tapping Sound
AFFECTED VEHICLE RANGE:
RANGE ROVER (LP) WA382672 to YA437311
DISCOVERY SERIES II (LT)Up to YA265404
DISCOVERY (U) WA753113 to XA795263
SITUATION:
NOISE FROM ENGINE VALVE TRAIN/ROCKER ARMS
Customer complaints of a rattling/tapping noise from the engine found to originate from rocker shaft area may be the result of the hardened push-rod
cup being insecure in the rocker arm.
RESOLUTION:
NOTE:
This bulletin supersedes and replaces TIB 12/01/981NAS.
INSPECT AND REPLACE ROCKER ARMS
Investigate customer complaints of valve rattling/tapping noise on vehicles within the above VIN ranges and identify rocker arms with loose
push-rod cups. If noisy or loose rocker arms are encountered during the inspection, replace all rocker arms with updated parts.
PARTS INFORMATION
WARRANTY CLAIMS
Normal warranty policy and procedures apply.
152
REPAIR PROCEDURE:
DETERMINE FAULTY ROCKER ARMS AND REPLACE
1. Refer to Workshop Manual, Section 12, Engine Repairs, and remove both rocker covers.
2. Determine that rocker arms with loose cups are the source of the noise.
3. Locate the rocker arm casting date code on each rocker arm.
CAUTION:
Only rocker arms with date codes '00' may be used to repair valve trains. Use of early production rocker arms may result in a reoccurrence
of the problem.
4. Refer to Overhaul Manual LRL0004ENG and replace all rocker arms manufactured prior to a '00' date code with new rocker arms having date
code '00' or above. (Figure 1)
5. Assemble and install rocker arm assemblies.
6. Install rocker arm covers.
7. Start the engine and confirm that the rattling/tapping noise has been resolved.
