REMOVAL & INSTALLATION
- With the engine removed from the vehicle and placed in a work stand, disconnect the spark plug wires from the spark plugs and remove the wires and bracket assembly from the attaching stud on the valve rocker arm cover(s) if so equipped. Disconnect the coil to distributor high tension lead at the coil. Remove the distributor cap and spark plug wires as an assembly. Remove the spark plugs to allow easy rotation of the crankshaft.
- Remove the fuel pump and oil filter. Slide the water pump by-pass hose clamp (if so equipped) toward the water pump. Remove the alternator and mounting brackets.
- Remove the crankshaft pulley from the crankshaft vibration damper. Remove the capscrew and washer from the end of the crankshaft. Install a universal puller, Tool T58P-6316-D or equivalent on the crankshaft vibration damper and remove the damper.
- Remove the cylinder front cover and crankshaft gear, refer to Cylinder Front Cover and Timing Chain in this Section.
- Invert the engine on the work stand. Remove the clutch pressure plate and disc (manual shift transmission). Remove the flywheel and engine rear cover plate. Remove the oil pan and gasket. Remove the oil pump.
- Make sure all bearing caps (main and connecting rod) are marked so that they can be installed in their original locations. Turn the crankshaft until the connecting rod from which the cap is being removed is down, and remove the bearing cap. Push the connecting rod and piston assembly up into the cylinder. Repeat this procedure until all the connecting rod bearing caps are removed.
- Remove the main bearings caps.
- Carefully lift the crankshaft out of the block so that the thrust bearing surfaces are not damaged. Handle the crankshaft with care to avoid possible fracture to the finished surfaces.
- Remove the rear journal seal from the block and rear main bearing cap.
- Remove the main bearing inserts from the block and bearing caps.
- Remove the connecting rod bearing inserts from the connecting rods and caps.
- If the crankshaft main bearing journals have been refinished to a definite undersize, install the correct undersize bearings. Be sure the bearing inserts and bearing bores are clean. Foreign material under the inserts will distort the bearing and cause a failure.
- Place the upper main bearing inserts in position in the bores with the tang fitting in the slot. Be sure the oil holes in the bearing inserts are aligned with the oil holes in the cylinder block.
- Install the lower main bearing inserts in the bearing caps.
- Clean the rear journal oil seal groove and the mating surfaces of the block and rear main bearing cap.
- Dip the lip-type seal halves in clean engine oil. Install the seals in the bearing cap and block with the undercut side of the seal toward the front of the engine.
- Carefully lower the crankshaft into place. Be careful not to damage the bearing surfaces.
- Check the clearance of each main bearing by using the following procedure:
- Place a piece of Plastigage® or its equivalent, on bearing surface across full width of bearing cap and about 1 / 4 in. (6mm) off center.
- Install cap and tighten bolts to specifications. Do not turn crankshaft while Plastigage® is in place.
- Remove the cap. Using Plastigage® scale, check width of Plastigage® at widest point to get the minimum clearance. Check at narrowest point to get maximum clearance. Difference between readings is taper of journal.
- If clearance exceeds specified limits, try a 0.001 in. (0.0254mm) or 0.002 in. (0.051mm) undersize bearing in combination with the standard bearing. Bearing clearance must be within specified limits. If standard and 0.002 in. (0.051mm) undersize bearing does not bring clearance within desired limits, refinish crankshaft journal, then install undersize bearings.
- Install all the bearing caps except the thrust bearing cap (no. 3 bearing on all except the 6-4.9L which use the no. 5 as the thrust bearing). BE sure the main bearing caps are installed in their original locations. Tighten the bearing cap bolts to specifications.
- install the thrust bearing cap with the bolts finger tight.
- Pry the crankshaft forward against the thrust surface of the upper half of the bearing.
- Hold the crankshaft forward and pry the thrust bearing cap to the rear. This will align the thrust surfaces of both halves of the bearing.
- Retain the forward pressure on the crankshaft. Tighten the cap bolts to specifications.
- Check the crankshaft end-play using the following procedures:
- Force the crankshaft toward the rear of the engine.
- Install a dial indicator (tools D78P-4201-F, -G or equivalent) so that the contact point rests against the crankshaft flange and the indicator axis is parallel to the crankshaft axis.
- Zero the dial indicator. Push the crankshaft forward and note the reading on the dial.
- If the end-play exceeds the wear limit listed in the Crankshaft and Connecting Rod Specifications chart, replace the thrust bearing. If the end-play is less than the minimum limit, inspect the thrust bearing faces for scratches, burrs, nicks, or dirt. If the thrust faces are not damaged or dirty, then they probably were not aligned properly. Lubricate and install the new thrust bearing and align the faces following procedures 21 through 24.
- On 6-4.9L engines with one piece rear main bearing oil seal, coat a new crankshaft rear oil seal with oil and install using Tool T65P-6701-A or equivalent. Inspect the seal to be sure it was not damaged during installation.
- Install new bearing inserts in the connecting rods and caps. Check the clearance of each bearing, following the procedure (18a through 18d).
- After the connecting rod bearings have been fitted, apply a light coat of engine oil to the journals and bearings.
- Turn the crankshaft throw to the bottom of its stroke. Push the piston all the way down until the rod bearing seats on the crankshaft journal.
- Install the connecting rod cap. Tighten the nuts to specification.
- After the piston and connecting rod assemblies have been installed, check the side clearance with a feeler gauge between the connecting rods on each connecting rod crankshaft journal. Refer to Crankshaft and Connecting Rod specifications chart in this Section.
- Install the timing chain and sprockets or gears, cylinder front cover and crankshaft pulley and adapter, following steps under Cylinder Front Cover and Timing Chain Installation in this Section.
- With the oil pan, oil pump and spark plugs removed, remove the cap from the main bearing needing replacement and remove the bearing from the cap.
- Make a bearing roll-out pin, using a bent cotter pin as shown in the illustration. Install the end of the pin in the oil hole in the crankshaft journal.
- Rotate the crankshaft clockwise as viewed from the front of the engine. This will roll the upper bearing out of the block.
- Lube the new upper bearing with clean engine oil and insert the plain (un-notched) end between the crankshaft and the indented or notched side of the block. Roll the bearing into place, making sure that the oil holes are aligned. Remove the roll pin from the oil hole.
- Lube the new lower bearing and install it in the main bearing cap. Install the main bearing cap onto the block, making sure it is positioned in proper direction with the matchmarks in alignment.
- Tighten the main bearing cap to specification.
CRANKSHAFT CLEANING AND INSPECTION
- Clean the crankshaft with solvent, and blow out all oil passages with compressed air. On the 6-4.9L engine, clean the oil seal contact surface at the rear of the crankshaft with solvent to remove any corrosion, sludge or varnish deposits.
- Use crocus cloth to remove any sharp edges, burrs or other imperfections which might damage the oil seal during installation or cause premature seal wear.
- Inspect the main and connecting rod journals for cracks, scratches, grooves or scores.
- Measure the diameter of each journal at least four places to determine out-of-round, taper or undersize condition.
- On an engine with a manual transmission, check the fit of the clutch pilot bearing in the bore of the crankshaft. A needle roller bearing and adapter assembly is used as a clutch pilot bearing. It is inserted directly into the engine crank shaft. The bearing and adapter assembly cannot be serviced separately. A new bearing must be installed whenever a bearing is removed.
- Inspect the pilot bearing, when used, for roughness, evidence of overheating or loss of lubricant. Replace if any of these conditions are found.
- On the 6-4.9L engine, inspect the rear oil seal surface of the crankshaft for deep grooves, nicks, burrs, porosity, or scratches which could damage the oil seal lip during installation. Remove all nicks and burrs with crocus cloth.
- Clean the bearing inserts and caps thoroughly in solvent, and dry them with compressed air.
- Inspect each bearing carefully. Bearings that have a scored, chipped, or worn surface should be replaced.
- The copper-lead bearing base may be visible through the bearing overlay in small localized areas. This may not mean that the bearing is excessively worn. It is not necessary to replace the bearing if the bearing clearance is within recommended specifications.
- Check the clearance of bearings that appear to be satisfactory with Plastigage® or its equivalent. Fit the new bearings following the procedure Crankshaft and Main Bearings removal and installation, they should be reground to size for the next undersize bearing.
- Regrind the journals to give the proper clearance with the next undersize bearing. If the journal will not clean up to maximum undersize bearing available, replace the crankshaft.
- Always reproduce the same journal shoulder radius that existed originally. Too small a radius will result in fatigue failure of the crankshaft. Too large a radius will result in bearing failure due to radius ride of the bearing.
- After regrinding the journals, chamfer the oil holes, then polish the journals with a No. 320 grit polishing cloth and engine oil. Crocus cloth may also be used as a polishing agent.
COMPLETING THE REBUILDING PROCESS
Fill the oil pump with oil, to prevent cavitating (sucking air) on initial engine start up. Install the oil pump and the pickup tube on the engine. Coat the oil pan gasket as necessary, and install the gasket and the oil pan. Mount the flywheel and the crankshaft vibration damper or pulley on the crankshaft.
Position the engine, cylinder head side up. Lubricate the lifters, and install them into their bores. Install the cylinder head, and torque it as specified. Insert the pushrods (where applicable), and install the rocker shaft(s) (if so equipped) or position the rocker.
Install the intake and exhaust manifolds, the distributor and spark plugs. Mount all accessories and install the engine in the car. Fill the radiator with coolant, and the crankcase with high quality engine oil.
Start the engine, and allow it to run at low speed for a few minutes, while checking for leaks. Stop the engine, check the oil level, and fill as necessary. Restart the engine, and fill the cooling system to capacity. Check and adjust the ignition timing. Run the engine at low to medium speed (800-2500 rpm) for approximately 1 / 2 hour, and retighten the cylinder head bolts. Road test the car, and check again for leaks.