D379B, D398B & D399 GENRERATOR SET ENGINES Caterpillar

Crankshaft

Usage:

Remove Crankshaft

start by:

a) remove fuel injection lines

b) remove rear timing gears

c) remove accessory drive gears and plate

d) remove intake manifolds

1. Remove bolts (2) that hold the oil pan base to the cylinder block. Remove the inspection covers from the side of the block.

2. Loosen connecting rod bolts (1) from the side opposite the way the block will be turned. This will permit easier removal of bolts after block is turned in the horizontal position.

3. Install a hoist to the engine lifting eyes. Put two nylon straps (3) through block and install a 1 1/2" steel bar (4). The bar must be as long as the cylinder block. With the engine off the floor, lift the lift truck and lower the hoist until engine is in position as shown. Install wooden blocks.

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NOTICE

Use care not to hit the floor while the engine is turned.

4. Install a 1"-14 NF bolt (6) in each end of crankshaft. Install a hoist and straps on bolts.

5. Remove rod caps and fasten rods in position with bolts and wire.

6. Remove main bearing caps (5) and bearings. Install rubber hose (7) on studs to prevent machined surface damage.

7. Lower the crankshaft with a hoist. Weight of crankshaft for D379 is 650 lb. (295 kg); D398 is 890 lb. (404 kg); D399 is 1100 lb. (499 kg).

Install Crankshaft

1. Fasten hoists and put crankshaft (1) in position in the cylinder block.

2. Install new upper halves (with oil holes) of main bearings in cylinder block. Put clean engine oil on all bearings.

3. Lift the crankshaft into position in the cylinder block. Remove hose (2) from threads of studs.

NOTE: When the bearing clearance is checked and the engine is in a vertical position, such as in the vehicle, the crankshaft will have to be lifted up and held against the upper halves of the main bearings to get a correct measurement with Plastigage (A). The Plastigage will not hold the weight of the crankshaft and give a correct indication. If the engine is in a horizontal position, such as on an engine stand, it is not necessary to hold the crankshaft up. Do not turn crankshaft when Plastigage is in position to check clearance.

4. Put new bearings (3) in main bearings caps. Use Plastigage to check bearing clearance. Install caps and tighten both nuts to a torque of 200 ± 10 lb. ft. (270 ± 14 N·m). Put a mark on the nuts and end of studs. Tighten nuts an extra 120° from the mark. Remove caps and check width of Plastigage to find bearing clearance. Bearing clearance must be .0048 to .0090 in. (0.122 to 0.229 mm) for new parts. Maximum permissible clearance for used parts is .015 in. (0.38 mm).

NOTE: Main bearing caps have numbers to identify their location in cylinder block. Install bearing caps so the number on cap is the same as number on cylinder block. Both numbers must be on same side of cylinder block.

5. Put clean engine oil on threads of studs and seat for nut. Install main bearing caps (4) and nuts. Install the thrust plates on dowel on rear cap. The dowels must not be extended more than .160 in. (4.06 mm) from counterbore face of bearing cap. Tighten the nuts to a torque of 200 ± 10 lb.ft. (270 ± 14 N·m). Put a mark on nuts and ends of studs and tighten nuts an extra 120° from mark.

6. Put the upper half of new rod bearings (5) in the rod. Put rod in position on the crankshaft.

7. Install lower half of new rod bearings (6) in caps (7). Put clean engine oil on bearings.

NOTE: Be sure the tabs on back of bearing fits in tab grooves of cap and on connecting rod. Install the bearing caps and bolts. Tighten the bolts first to a torque of 40 ± 4 lb.ft. (55 ± 5 N·m). Put a mark on bolt heads and bearing caps. Tighten bolts again 120° from mark. Only four bolts can be tightened in this way. The remainder of the bolts must be tightened with the engine in the vertical position.

8. Use tool group (B) to check crankshaft end play as controlled by thrust plates. End play must be .005 to .021 in. (0.13 to 0.53 mm). Maximum permissible end play is .035 in. (0.89 mm).