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98. Lower Crankcase Installation



Lower Crankcase Installation

^ Tools Required
- EN 46109 Engine Front Cover Installation Guide Pins
- J 39946 Crankshaft Socket - 4.0L and 4.6L
- J 45059 Angle Meter

1. Ensure the surfaces to be sealed are free of any sealant and free of any nicks, gouges or scratches. Wipe all sealing surfaces clean with a dry, lint-free cloth.





2. Place a 5 mm (0.197 inch) spot of RTV sealant GM P/N 12378521, (Canadian P/N 88901148), or equivalent at the 2 points where the crankshaft rear oil seal meets the split line of the engine block.





3. Completely fill and slightly overfill the engine block seal groove with a continuous bead of RTV sealant GM P/N 12378521, (Canadian P/N 88901148), or equivalent.





4. Ensure the RTV sealant GM P/N 12378521, (Canadian P/N 88901148), or equivalent bead is higher than the rail surface by 3 mm (0.118 inch).





5. Using a suitable tool spread the sealant in the area near the oil drain back passages away from the oil drain back passages toward the outboard edge of the rail surface.





6. To prevent shifting of the lower crankcase install one M8 of the EN 46109 into a bolt hole in each rail.





7. Install the cleaned lower crankcase onto the engine.





8. Using a rubber mallet gently tap the lower crankcase into position. Inspect the upper-to-lower crankcase joint in order to make sure the lower crankcase is fully seated on the cylinder block.





9. Using a small long blade screwdriver clean out any sealant in the oil drain back passages (1).





10. Important: Remove the outer seal of the NEW oil distribution plate if equipped. DO NOT remove the inner seal. DO NOT use sealant in the place of the inner seal.

Using a NEW oil distribution plate completely fill and slightly overfill RTV sealant GM P/N 12378521, (Canadian P/N 88901148), or equivalent in the outer groove (1) of the oil distribution plate place.





11. Ensure the RTV sealant GM P/N 12378521, (Canadian P/N 88901148), or equivalent bead is higher than the oil distribution plate sealing surface by 3 mm (0.118 inch).





12. To prevent shifting of the oil distribution plate install one M6 of the EN 46109 into a bolt hole in each side of the lower crankcase.





13. Install the NEW oil distribution plate.





14. Loosely install the oil distribution plate bolts.
15. Remove both of the M6 EN 46109 .

16. Notice: Refer to Fastener Notice in Service Precautions.

Tighten the oil distribution plate bolts.
^ Tighten the oil distribution plate bolts to 10 Nm (89 inch lbs.).





17. Using a small long blade screwdriver clean out any sealant in the oil drain back passages.





18. Install the lower crankcase main bearing bolts. The single stud-head bolt (1) used for oil pump pick-up mounting goes in the inboard position of the second set of main bearing bolts from the front of the engine.





19. Tighten the main bearing bolts in the proper sequence.
1. First Pass
^ Tighten the main bearing bolts (1-20) to 20 Nm (15 ft. lbs.) in the proper sequence.
2. Final Pass
^ Tighten the main bearing bolts (1-20) an additional 65° in the proper sequence using the J 45059 .
20. Remove both of the M8 EN 46109 from the perimeter bolt holes.





21. Loosely install the crankcase perimeter bolts on the right side.





22. Loosely install the crankcase perimeter bolts on the left side.





23. Tighten the crankcase perimeter bolts in the sequence shown.
^ Tighten the crankcase perimeter bolts to 30 Nm (22 ft. lbs.).





24. Using a small long blade screwdriver verify that the oil drain back passages are clear of sealant.
25. Using the J 39946 rotate the crankshaft until the number one piston is at top dead center (TDC) and the crankshaft key way is approximately at the 7 o'clock position.