Fitting Crankshaft Main or Connecting Rod Bearings with Plastigage

1. Clean crankshaft journals. Inspect journals and thrust faces for nicks, burrs or roughness that would cause premature bearing wear. When replacing standard bearings with new bearings, it is good practice to fit bearing to minimum specified clearance. If desired clearance cannot be obtained with a standard bearing, try a 0.050mm (0.002 inch) undersize bearing to obtain proper clearance.

    CAUTION: Do not position jack under crankshaft pulley (6312) . Crankshaft post damage will result.

2. If fitting crankshaft main bearing (6333) in vehicle, position a jack under counterweight adjoining crankshaft main bearing which is being checked. Support crankshaft (6303) with jack so its weight will not compress Plastigage and provide an erroneous reading.

3. Place a piece of Plastigage D81L-6002-B or equivalent on bearing surface across full width of bearing cap and about 6.35mm (1/4 inch) off center.

4. Install cap and tighten bolts to specification. Do not turn crankshaft while Plastigage is in place.

5. Remove cap. Using Plastigage scale, check width of Plastigage at widest point to get minimum clearance. Check at narrowest point to get maximum clearance. Difference between reading is taper of journals.
   
   
   
   

6. If bearing clearance exceeds the specified limits, try using one of the various combinations of undersize bearings as directed by the accompanying table. Use of any other bearing combination is not recommended. Bearing clearance must be within specified limits. Refer to appropriate engine section under Specifications, for crankshaft main bearing and connecting rod bearing clearance limits. If use of these bearing combinations do not bring clearance to the desired limits, refinish the crank journal to 0.254mm (0.010 inch) undersize, and use the appropriate undersize bearing.

7. After bearing has been fitted and cleaned, apply a light coat of XO-10W30-QSP (ESE-M2C153-E) or equivalent engine oil to journal and bearings. Install bearing cap. Tighten cap bolts to specification. Refer to Section 03-01A (3.8L) or Section 03-01B (5.0L).

8. Repeat procedure for remaining bearings that require replacement.
   
   

   FOR THIS AMOUNT BEARING CLEARANCE EXCESS		USE THIS BEARING SIZE
   mm	Inch	UPPER BEARING		LOWER BEARING
   		mm	Inch	mm	Inch
   0.0-0.013	0.0-0.0005	0.025	0.001 U.S.	STANDARD	STANDARD
   0.013-0.026	0.0005-0.0010	0.025	0.001 U.S.	0.025	0.001 U.S.
   0.026-0.039	0.0010-0.0015	0.050	0.002 U.S.	0.025	0.001 U.S.
   0.039-0.052	0.0015-0.0020	0.050	0.002 U.S.	0.050	0.002 U.S.