Engine - Oil Pan Bolt Leakage
No: 12/02/98/NASRef: TIB 12/08/96/US
Issue: 2
Date: 06/26/98
Oil Pan Bolt Oil Leakage
AFFECTED VEHICLE RANGE:
RANGE ROVER (LP) up to VA374534
DISCOVERY (LJ) up to VA738466
SITUATION:
OIL LEAKAGE FROM OIL PAN BOLTS
On all V8 engines with cross-bolted main bearing caps, the drillings for the four oil pan bolts, indicated by arrows in Figure 1 pass through to the adjacent cross bolt holes. An oil leak path can develop down the thread of these oil pan bolts.
Discovery 4.0-liter engine oil pick-up tube bolts also provide an oil path to the sump bolts.
RESOLUTION:
REPLACE OIL PAN BOLTS
In the event of oil leakage around the heads of the oil pan bolts, remove all traces of oil and replace the bolts with new "patch" bolts or use Loctite(R) 577 to seal the bolts.
If the oil pan has been removed to seal leaks as described in TIB 12/08/96/US or for other maintenance reasons, new patch bolts or Loctite(R) must be used for assembly. On Discovery 4.0 liter engines the oil pick-up tube bolts should be removed, cleaned and have Loctite applied to eliminate oil travel to the pan bolt hole.
PARTS INFORMATION
WARRANTY CLAIMS
Normal warranty policy and procedures apply.
REPAIR PROCEDURE:
INSTALL NEW BOLTS
CAUTION:
Ensure that the longer bolt LSZ100000 is used ONLY at the Discovery oil cooler pipe bracket location (See Figure 1, Location "A").
NOTE:
The new bolts incorporate a sealant patch and are fitted to V8 engines in production from the safe VINs.
If patch bolts are removed for any reason they must be replaced with new patch bolts or have Loctite(R) sealant applied upon assembly.
1. If only replacing the four oil pan bolts to rectify a leak from this area, perform the following:
^ Remove the four old bolts (Figure 1 positions 12, 4, 5).
^ Hand tighten the new patch bolts.
^ Torque new bolts to 23 Nm (17 lbf.ft.) using the Engine Overhaul Manual sequence (Figure 1).
2. If applying Loctite(R) on used oil pan bolts to rectify a leak from this area, perform the following:
^ Remove the four bolts (Figure 1 positions 12, 4, 5).
^ Thoroughly clean all bolts and oil pan area.
^ Apply Loctite(R) 577 to the bolt threads.
^ Install and torque four bolts to 23 Nm (17 lbf.ft.) using the Engine Overhaul Manual sequence (Figure 1).
3. If sealing a Discovery 4.0 liter oil pan for leakage, refer to TIB 12/08/96/US and perform the repair noting the following enhancements:
^ After oil pan removal, remove oil pick-up tube securing bolts (Figure 2).
^ Apply Loctite(R) 577 to cleaned bolts and install.
^ Torque oil pick-up tube bolts to 8 Nm (6 lbf.ft.).
^ Thoroughly clean all bolts and oil pan area.
^ Hand tighten new patch bolts or apply Loctite(R) 577 to the threads of used bolt in Figure 1 positions 1, 2, 4, 5 and install.
^ Torque bolts to 23 Nm (17 lbf.ft.) using the Engine Overhaul Manual sequence (Figure 1).