REMOVAL & INSTALLATION
See Figures 1 through 13
Before removing the crankshaft, check main bearing clearances as described in Main Bearing Clearance Check. This check should always be performed before and after any repairs to the crank or bearings.
- Remove the piston and connecting rod assemblies.
- Check crankshaft thrust clearance (end play) before removing the crank from the block. Using a small prybar, gently force the crankshaft the extent of its travel forward, and measure thrust clearance at the center main bearing (No. 4 bearing on 6-cylinder engines, No. 3 on 4-cylinder engines) with a feeler gauge. Pry the crankshaft the extent of its rearward travel, and measure the other side of the bearing. If clearance is greater than that specified, the thrust washers must be replaced.
- Using a punch, mark the corresponding main bearing caps and saddles according to position: one punch (dot) on the front main cap and saddle, two on the second, three on the third, etc. This ensures correct reassembly.
- Remove the main bearing caps after they have been marked.
- Remove the crankshaft from the block. The crankshaft, even from a small engine is heavy. Be prepared to control the weight, particularly if working under the engine.
- Replace the front and rear crankshaft oil seals.
- Place the crankshaft on the cylinder block.
- Install the main bearing caps and the lower thrust washers. Apply a light coat of engine oil on the threads and under the heads of the main bearing cap bolts.
- Install and tighten the main bearing caps in several passes. If any one cap does not meet torque specification, replace the main bearing cap bolt.
- Mark the front of the main bearing cap bolt with paint, then retighten the cap bolts by 90° in the order needed.
If new bearings are being installed, be sure to check the clearances first.
- Check the mark making sure it is now facing at a 90° angle to the front.
- Check that the crankshaft turns smoothly, then check the thrust clearance.
CLEANING AND INSPECTION
Crankshaft inspection and servicing should be handled exclusively by a reputable machinist, as most of the necessary procedures require a dial indicator, fixing jig, a large micrometer, and machine tools such as a crankshaft grinder. While at the machine shop, the crankshaft should be thoroughly cleaned (especially the oil passages) and crack-checked. Additionally, have it checked for: main journal diameter, crank pin (connecting rod journal) diameter, taper, out-of-round, and run-out. Wear, beyond specification limits, in any of these areas means the crankshaft must be reground or replaced.
MAIN BEARING CLEARANCE CHECK
Checking main bearing clearances is done in the same manner as checking connecting rod clearances.
- With the crankshaft installed, remove the main bearing cap to be checked. Clean all oil from the bearing insert in the cap and from the crankshaft journal, as the Plastigage® material is oil-soluble.
- Lay a strip of Plastigage® along the full width of the bearing cap (or along the width of the crank journal if the engine is out of the truck and inverted).
- Install the bearing cap and tighten to specification.
Do not rotate the crankshaft with the Plastigage® installed.
- Remove the bearing cap and determine bearing clearance by comparing the width of the now-flattened Plastigage® with the scale on the Plastigage® envelope. Journal taper is determined by comparing the width of the Plastigage® strip near its ends. Rotate the crankshaft 90° and retest, to determine journal eccentricity.
- Repeat for the remaining bearings. If the bearing journal and insert appear in good shape (with no unusual wear visible) and are within tolerances, no further main bearing service is required. If unusual wear is evident and/or the clearances are outside specifications, the bearings must be replaced and the cause of their wear found.
Main bearings can be replaced with the crankshaft in the engine (with the engine still in the truck) or with the engine on a work stand or bench. Both procedures are covered here. The main bearings must be replaced if the crankshaft has been reground; the replacement bearing being available in various undersize increments from most auto parts jobbers or your Toyota dealer.Engine Removed
- Remove the crankshaft from the engine block.
- Remove the main bearing inserts from the bearing caps and from the main bearing saddles. Remove the thrust washers from the No. 3 (4 cylinder) or No. 4 (6 cylinder) crank journal.
- Thoroughly clean the saddles, bearing caps, and crankshaft.
- Make sure the crankshaft has been fully checked and is ready for reassembly. Place the upper main bearings in the block saddles so that the oil grooves and/or oil holes are correctly aligned with their corresponding grooves or holes in the saddles.
On the 3F-E, the outer diameter varies with each bearing location; additionally, all the main bearings have oil holes except Nos. 1 and 4 on the lower side.
- Install the thrust washers on the center main bearing, with the oil grooves facing out.
- Lubricate the faces of all bearings with clean engine oil, and place the crankshaft in the block. On 3F-E, apply sealant to the block in the location of the front and rear main bearing cap contact points.
- Install the main bearing caps in numbered order with the arrows or any other orientation marks facing forward. Tighten the cap bolts in the correct sequence in two or three passes. Rotate the crankshaft after each pass to ensure even tightness.On 3VZ-E engines, once the caps are installed, bring the bolts to 45 ft. lbs. (61 Nm) in several passes and in the correct order. If any bolt will not tighten to this specification, the bolt must be replaced. Mark the front face of each bolt with paint; turn each bolt an additional 90° so that the paint marks now face the side of the engine. Check that the crankshaft turns smoothly.
- Check the crankshaft thrust clearance (end play). If clearance is outside specifications (too sloppy), install a new set of oversize thrust washers and check clearance again.
See Figures 14 and 15
- Remove the main bearing caps and keep them in order.
- Make a bearing roll-out pin from a cotter pin.
- Use the cotter pin tool to carefully roll out the old bearing inserts from the upper side of the crankshaft journal, noting the positions of the oil grooves and/or oil holes so the new inserts can be correctly installed. This rolling-out of the bearing takes a light touch and a bit of patience. The bearing must be rotated a full 180° before it can be removed. Take great care not to mark or scratch the crank journal with the cotter pin.
- Roll each new insert into its saddle after lightly oiling the crankshaft-side face of each. Make sure the notches and/or oil holes are correctly positioned.
- Replace the bearing inserts in the caps with new inserts. Oil the face of each, and install the caps in numbered order with the arrows or other orientation marks facing forward.
- Install the bearing cap following the correct procedure.