Crankshaft Bearing Clearance Measurement Procedure
Place a length of fresh, room temperature plastic gaging material all the way across all the crankshaft bearing journals.
- Identify the proper order of the main bearing caps. The main bearing caps are numbered 1 (1) through 4, with the front main bearing cap marked with the number 1. The arrow (2) is to be oriented to the front of the engine.
Crankshaft Bearing Cap (1) - Install [4x]
- CAUTION:
This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component.
NOTE:The inner bearing cap bolts are longer than the outer bearing cap bolts.
Install the inner bearing cap bolts (4) and outer bearing cap bolts (3) and hand tighten.
- Using a plastic-face hammer, tap the bearing caps into place.
- Install the crankshaft bearing cap side bolts (1, 2) and hand tighten.
- Using a plastic-face hammer, tap the crankshaft rearward, then forward in order to align the thrust bearings.
- Using the EN-45059 Angle Meter, tighten the inner and outer crankshaft bearing cap bolts in sequence. Fastener Specifications
- Using the EN-45059 Angle Meter, tighten the side crankshaft bearing cap bolts in sequence. Fastener Specifications
- Ensure that the crankshaft turns without binding or noise.
Crankshaft End Play Measurement
- Place a EN-7872 Magnetic Base Dial Indicator at the crankshaft nose.
- Gently force the crankshaft to the extreme front and rear positions with a pry tool while monitoring the movement of the dial indicator.
- The crankshaft end play should not exceed specifications. Engine Mechanical Specifications
- If the specifications are exceeded inspect the thrust bearing thrust OD and the crankshaft thrust wall for wear and/or excessive runout. Engine Mechanical Specifications
- Replace the thrust bearing or crankshaft as necessary.
- After reaching final torque, allow the assembly to sit for 2 minutes.
Remove and DISCARD the crankshaft bearing cap side bolts (1 and 2).
- Remove and DISCARD the crankshaft bearing cap outer bolts (3).
- Remove and DISCARD the crankshaft bearing cap inner bolts (4).
Using the GE-6125-1B Slide Hammer Adapter (2) and EN-49102 Crankshaft Bearing Cap Remover (3), remove the 4 crankshaft bearing caps (1).
Determine the crankshaft bearing clearance by comparing the width of the flattened plastic gaging material at its widest point with the graduation on the gaging material container.
- Compare your measurements with the Engine Mechanical Specifications
. If the new bearings do not provide the proper crankshaft to bearing clearance, inspect the following:
- Re-measure the crankshaft journals for the correct specified size and ensure the proper new bearings are being installed. If the crankshaft journals are incorrectly sized, replace or regrind the crankshaft. Crankshaft machining is permitted and undersized bearings are available.
- Re-measure the engine block crankshaft bearing bore diameter to ensure proper size. The engine block crankshaft bearing bore is not machinable and the block must be replaced if out of specification.
- Clean the plastic gaging material from the crankshaft bearing journals with a soft, lint-free cloth.
Crankshaft (1) - Remove
Apply a liberal amount of crankshaft prelube or clean engine oil to the upper (1) and lower (2) bearing surfaces. Adhesives, Fluids, Lubricants, and Sealers
Crankshaft (1) - Install
Identify the proper order of the main bearing caps. The main bearing caps are numbered 1 (1) through 4, with the front main bearing cap marked with the number 1. The arrow (2) is to be oriented to the front of the engine.
Crankshaft Bearing Cap (1) - Install [4x]
- CAUTION:
This vehicle is equipped with torque-to-yield or single use fasteners. Install a NEW torque-to-yield or single use fastener when installing this component. Failure to replace the torque-to-yield or single use fastener could cause damage to the vehicle or component.
NOTE:The inner bearing cap bolts are longer than the outer bearing cap bolts.
Install the NEW inner bearing cap bolts (4) and NEW outer bearing cap bolts (3) and hand tighten.
- Using a plastic-face hammer, tap the bearing caps into place.
- Install the NEW crankshaft bearing cap side bolts (1, 2) and hand tighten.
- Using a plastic-face hammer, tap the crankshaft rearward, then forward in order to align the thrust bearings.
- Using the EN-45059 Angle Meter, tighten the inner and outer crankshaft bearing cap bolts in sequence. Fastener Specifications
- Using the EN-45059 Angle Meter, tighten the side crankshaft bearing cap bolts in sequence. Fastener Specifications
- Ensure that the crankshaft turns without binding or noise.
Liberally lubricate the cylinder walls, piston rings and piston skirts with engine oil.
- The piston is directional and must be installed in the engine block in the proper direction. The dot on the top of the piston must face the front of the engine.
- Ensure the bowl of the piston faces the intake.
- Select the correctly numbered piston/connecting rod assembly for the cylinder. A dot (1) showing proper piston orientation is located on the top of the piston. Piston is model dependent.
- NOTE:
If the connecting rod bearings have been used in a running engine, you must replace them with NEW connecting rod bearings for reassembly.
Install a NEW connecting rod bearing (1) into the connecting rod (2).
- Install the EN-46121 Connecting Rod Guide Pin Set (3) into the connecting rod bolt holes.
- Compress the piston rings using the a ring compressor sleeve or equivalent.NOTE:
When installing a piston into a cylinder, use a ring compressor sleeve or equivalent for best results. The following features should be looked for when selecting a ring compressor sleeve.
- Hard anodized and Teflon coated for low friction and prolonged wear resistance.
- Smooth radius that tapers down to the specific bore size.
- Sleeve should compress the piston rings smoothly and evenly.
- Using a ring compressor sleeve greatly reduces the difficulty with installing thin high-performance oil rings.
If a ring compressor sleeve is unavailable, a universal ring compressor will work but is more difficult to use.
- NOTE:
Extreme care must be used when installing the piston and connecting rod to ensure the rod does not scrape or nick the cylinder bore, the oil jets, or the crankshaft surfaces.
Using both hands, slowly guide the piston and connecting rod assembly (1) into the cylinder from the top and bottom of the cylinder. DO NOT allow the connecting rod to contact the cylinder wall.
- Tap the piston into its bore with a hammer handle. Guide the connecting rod to the connecting rod journal using the EN-46121 Connecting Rod Guide Pin Set while gently tapping the piston into place. Hold the ring compressor sleeve or equivalent against the engine block until all the rings have entered the cylinder bore.
Remove the EN-46121 Connecting Rod Guide Pin Set (1) from the connecting rod bolt holes.
To properly align the crankshaft thrust bearings, the final thrust of the crankshaft MUST be in the forward direction.
Do not rotate the crankshaft.
The crankshaft bearings CAN be reused after checking the clearance if the bearings have never been used in a running engine.
To properly align the crankshaft thrust bearings, the final thrust of the crankshaft MUST be in the forward direction.
Refer to Fastener Caution .