Caterpillar D399 Generator Set

Tools: crane, dial indicator, shims, torque wrench

1. Loosen all bolts connecting base to foundation; loosen all bolts fastening engine supports and generator supports to base.
2. Ensure enough clearance between bolts and bolt holes in base, engine supports, generator supports at all locations.
3. Check clearance between base and foundation at all mounting locations; use shims to prevent deflection; tighten base-to-foundation bolts to final torque.
4. While generator supported by crane, loosen all bolts (2) fastening generator to flywheel housing; tighten alternate bolts to final torque; check clearance between base and engine and generator support
5. Tighten all bolts fastening engine supports and generator supports to base to half of final torque; loosen all bolts (2); measure gap between generator and flywheel housing; ensure bolts centered in c
6. Gaps at (E), (F), (G), (H) should be more than 0.03 mm (0.001 inch) and less than 0.13 mm (0.005 inch); adjust shims or move rear of generator right or left.
7. After shim correction, tighten generator support bolts to half of final torque 450 N-m (332 Ib ft); check gaps; repeat until 0.13 mm (0.005 inch) or less; begin with Step 5.
8. Install dial indicator on base with tip next to support mounting bolt (4); put tip on support (3); check while tightening bolt to final torque; if indicator moves more than 0.13 mm (0.005 inch), insta

Tools: shims, torque wrench

1. Loosen all bolts connecting base to foundation; loosen all bolts fastening generator supports and engine supports to base.
2. Ensure clearance between bolts and bolt holes in base, engine supports, generator supports at all locations.
3. Check clearance between base and foundation at all mounting locations; use shims to prevent base deflection; tighten base-to-foundation bolts to final torque.
4. Check clearance between base and engine, base and engine supports, base and generator supports over entire length; use shims to prevent support deflection; tighten all mounting bolts to final torque.

Tools: torque wrench, shims

1. Loosen the sixteen close coupled adapter bolts (2); visually ensure they are centered in clearance holes.
2. Check gaps at 3, 6, 9, and 12 o'clock positions; use 2, 4, 8, and 10 o'clock if 12 and 6 are inaccessible.
3. If gaps are between 0.03 mm (0.001 inch) and 0.13 mm (0.005 inch), tighten all bolts; alignment check complete. If not, loosen bolts fastening generator to base frame; adjust shims; move rear of gener
4. After adjustment, tighten generator mounting bolts to one half of standard torque 450 N-m (332 lb ft); repeat procedure starting with Step 1.

⚠ Damage to engine and generator can result if electric set is operated with a plate assembly that does not have proper clearance.

⚠ If N or O is less than initial A, disassemble and check coupling plate for bowing; replace if bowed.

Tools: dial indicator, straight edge, magnetic bases, crane, torque wrench, 17 5N-4478 Plates

1. Ensure generator is disengaged from engine; clean generator support and base contact surfaces; remove protective material from flywheel pilot bearing bore and coupling contact surface.
2. Remove two engine side covers; rotate engine until no. 1 crankshaft throw is perpendicular; measure crankshaft end play with dial indicator; record as A and divide by two for B.
3. With crankshaft at extreme forward position, measure distance from straight edge to flywheel housing mounting surface (C) and flywheel pilot surface (D); subtract D from C for E.
4. Remove coupling bolts and washers; remove plates, shims, and exhaust fan; lift rotor; locate rotor so air gap equal; move rotor to extreme rear.
5. Place dial indicator on vertical surface of heat sink at rear of rotor shaft; measure rotor end play (approximately 3.81 to 7.62 mm); record F and divide by two for G.
6. Move rotor to extreme rear; position straight edge across mounting ring diameter; measure distance to mounting ring surface (H) and hub mounting surface (I); subtract H from I for J.
7. Bolt a standard set of 17 5N-4478 Plates together; measure thickness in two locations along contour; average as K.
8. Determine number of shims: subtract B, E, G, K from J for L; divide L by 0.8 mm (0.03 inch) for M; round up.
9. Put coupling plate in flywheel bore; check clearance between coupling plate outside diameter and flywheel bore inside diameter.
10. Install coupling plate assembly, bolts (6) and calculated shims; tighten bolts (5) in 180 degree intervals in three stages to 525 + 25 N-m (390 + 20 lb ft).
11. Install guide bolts in flywheel; put generator on engine; install bolts (10); tighten to 100 N-m (75 lb ft) in pairs at 180 degree intervals in three stages.
12. While crane supports generator, place dial indicator on heat sink vertical surface; push generator forward within + 0.50 mm (+ 0.0200 inch) of midpoint of end play.
13. Install fan mounting bolts (11) into flywheel; tighten to 200 N-m (150 Ib ft) in pairs at 180 degree intervals in three stages.
14. Place dial indicators on no. 1 crankshaft throw and heat sink; push crankshaft forward; check crankshaft end play 0.178 to 0.635 mm and heat sink end play 0.076 to 0.635 mm; record N and O.
15. If N or O is less than initial A, disassemble; check coupling plate for bowing; replace if bowed; check calculations; install generator and repeat steps 13 and 15.

⚠ Damage to engine and generator can result if electric set is operated with a plate assembly that does not have proper clearance.

Tools: dial indicator, indicator assembly, bar, torque wrench, guide bolt, crane

1. Remove dirt, burrs, paint from generator support and base contact surfaces; remove protective material from flywheel pilot bearing bore and coupling contact surface.
2. Remove timing pointer cover; install indicator assembly on front of engine; tip contacts crankshaft pulley face.
3. Position plate assembly in flywheel bore; check clearance between plate outside diameter and bore inside diameter.
4. Install full shim pack and plate assembly on generator with bolts; tighten bolts to 525 + 45 N-m (390 + 30 lb ft).
5. Install guide bolt in flywheel; put generator on engine; install bolts (9) and (10); tighten but do not bend locks under bolts (8).
6. Use dial indicator to check crankshaft end play; if reading differs from initial, remove generator and enough shims to get original end play.
7. Install generator again and check crankshaft end play; after correct shims, bend locks under bolts (8).