Piston, Connecting Rod, and Bearing Installation (LAT, LE5, LE9)

Special Tools

• EN-43966-1:  Connecting Rod Guides
• J 45059:  Angle Meter
• EN-47836:  Piston Ring Compressor

For equivalent regional tools, refer to Special Tools .

Fig 1: View Of Connecting Rod Guides
Courtesy of GENERAL MOTORS CORP.
1. Install the connecting rod bearings. Use NEW bearings.
   1. Install the bearing inserts into the connecting rod and the connecting rod cap.
   2. Lubricate the connecting rod bearings with engine oil.
2. Install the EN-43966-1:  guides (1) into the connecting rod bolt holes. This protects the crankshaft journal during piston and connecting rod installation.
3. Install EN-47836:  compressor, piston, and the connecting rod to the correct bore.
   1. Stagger each piston ring end gap equally around the piston.
   2. Lubricate the piston and the piston rings with engine oil.
   3. Do not disturb the piston ring end gap location.
   4. The piston must be installed so that the mark on the top of the piston faces the front of the engine.
   5. Place the piston in its matching bore.
   6. Tap the piston into its bore with a hammer handle. Guide the connecting rod to the connecting rod journal while tapping the piston into place.
   7. Hold the EN-47836:  compressor against the engine block until all the rings have entered the cylinder bore.
   8. Remove the connecting rod guides from the connecting rod bolt holes.
Fig 2: View of Connecting Rod Cap
Courtesy of GENERAL MOTORS CORP.
NOTE: Ensure that the connecting rod cap is properly oriented on the connecting rod.
4. Install the connecting rod cap (1).
CAUTION: Refer to Fastener Caution .
5. Install the connecting rod bolts. Always use new bolts. Tighten the connecting rod bolts to 25 N.m (18 lb ft), plus 100 degrees using the J 45059:  meter.
6. Install the remaining connecting rods and piston assemblies.
Fig 3: Measuring Connecting Rod Side Clearance
Courtesy of GENERAL MOTORS CORP.
7. Measure the connecting rod side clearance with a feeler gage (1).

   The correct clearance is 0.07-0.37 mm (0.0027-0.0145 in).