66. Piston, Connecting Rod, and Bearing Installation
Piston, Connecting Rod, and Bearing InstallationTools Required
* J8037 Piston Ring Compressor
* J8087 Cylinder Bore Gage
Piston Selection
Important: The coating on the piston allows for an interference fit between the cylinder and the bore. The piston diameter can NOT be measured accurately because the piston coating is not a consistent thickness. Do NOT measure the piston diameter. To select the correct piston for installation, the cylinder bore must be measured. If the cylinder bore diameter is within service specifications, install the original piston/ connecting rod assembly or a new, standard size piston/connecting rod assembly. A used piston/ connecting rod assembly may be reinstalled if, after cleaning and inspection, the piston is not damaged. If the cylinder bore is NOT within specifications, the cylinder must be resized to accept a new, oversized piston For proper piston fit, the engine block cylinder bores should not have excessive wear or taper.
1. Inspect the engine block cylinder bore.
2. Inspect the piston/connecting rod assembly for damage.
3. Use the id 8087 and measure the cylinder bore diameter.
4. Measure the J8087 with a micrometer and record the reading.
5. Compare the cylinder bore measurement to the specifications.
5.1. If the cylinder bore is within specifications, select the original piston or a new, original size piston.
5.2. If the cylinder bore is not within specifications, select the next oversized piston/connecting rod assembly, then bore and hone the cylinder bore to fit the oversize piston.
Piston Installation
1. Coat the following components with clean engine oil:
- The piston
- The piston rings
- The cylinder bore
- The bearing surfaces
2. Install rubber fuel line onto the connecting rod bolts.
Important: The mark on the top of the piston must face the front of the engine block. When assembled, the flanges on the connecting rod and cap should face to the front of block on the left bank and to the rear of block on the right bank.
3. Install the piston, connecting rod and upper connecting rod bearing through the top of the engine block.
4. Install the J8037 onto the piston and compress the piston rings.
5. Use the J8037 and lightly tap the top of the piston with a wooden hammer handle.
6. Hold the J8037 firmly against the engine block until all of the piston rings have entered the cylinder bore.
7. Use the rubber fuel line in order to guide the connecting rod onto the crankshaft journal.
8. Remove the rubber fuel line.
9. Install the connecting rod cap and lower connecting rod bearing.
Notice: Refer to Fastener Notice in Service and Precautions.
Fastener Notice
Important: When installing the piston/connecting rod assembly, NEW connecting rod nuts must be installed.
10. Install the new connecting rod nuts.
Tighten the connecting rod nuts to 30 Nm (22 lb ft) plus an additional 90 degrees.
11. Once the piston and connecting rod assemblies have been installed, lightly tap each connecting rod assembly, parallel to the crankpin, in order to make sure that they have side clearance.
12. Use a feeler gage or a dial indicator to measure the side clearance between the connecting rod caps. The rod side clearance should be 0.384-0.686 mm (0.0151-0.0270 inch).