Caterpillar 3408C 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.

⚠ Replace belts for multiple groove pulleys in matched sets.

Tools: Belt tension gauge (110 N / 25 lb force)

1. Remove the belt guard.
2. Loosen mounting bolt (2) and adjusting nuts (1).
3. Turn adjusting nuts to increase or decrease belt tension.
4. Check deflection is 13 to 19 mm with 110 N applied midway.
5. Tighten the adjusting nuts; tighten the mounting bolt.
6. Reinstall the belt guard.
7. Check adjustment again after 30 minutes at rated rpm if new belts.

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).

⚠ Do not use a high concentration of caustic cleaner to clean the core.

⚠ Maximum air pressure at the nozzle must be less than 205 kPa (30 psi).

Tools: Pressure air supply (maximum 205 kPa / 30 psi at nozzle)

1. Remove the core. Refer to the Service Manual for the procedure.
2. Turn the aftercooler core upside-down in order to remove debris.
3. Back flush the core with cleaner (1U-5490 or 174-6854 Hydrosolv).
4. Steam clean the core to remove residue; flush the fins.
5. Wash the core with hot, soapy water; rinse thoroughly with clean water.
6. Dry the core with compressed air in the reverse direction of normal flow.
7. Inspect the core for cleanliness; pressure test; repair if necessary.
8. Install the core. Refer to the Service Manual for the procedure.

⚠ All lead-acid batteries contain sulfuric acid; wear face shield and protective clothing.

Tools: 245-5829 Coolant Battery Tester Refractometer

1. Remove the filler caps; maintain the electrolyte to the FULL mark.
2. Add distilled water if necessary; avoid artificially softened water.
3. Check electrolyte condition with the 245-5829 Coolant Battery Tester Refractometer.
4. Clean battery case with baking soda/water or ammonia/water solution; rinse.
5. Clean terminals and cable clamps with fine grade sandpaper.
6. Coat clamps and terminals with 5N-5561 Silicone Lubricant, petroleum jelly or MPGM.
7. Clean the battery case; keep the batteries clean.

⚠ Pressurized System: Hot coolant can cause serious burns.

⚠ Stop the engine and wait until cooling system components are cool.

Tools: 9S-8140 Pressurized Pump Group (filler cap pressure test)

1. Observe coolant level in recovery tank; maintain to COLD FULL mark.
2. Loosen filler cap slowly to relieve pressure; remove the filler cap.
3. Pour proper coolant mixture into tank; do not fill above COLD FULL.
4. Clean filler cap and receptacle; reinstall; inspect system for leaks.
5. Without a recovery tank, maintain level within 13 mm of filler pipe bottom.
6. Clean and inspect filler cap gaskets; replace damaged cap.

⚠ Perform this maintenance with the engine stopped.

⚠ A plugged crankcase breather will cause excessive crankcase pressure.

1. Loosen hose clamp (1) and remove the hose from breather assembly (2).
2. Loosen retaining clamp (3); remove the breather assembly and seal (4).
3. Wash the breather element in clean, nonflammable solvent.
4. Allow the breather element to dry before installation.
5. Install a clean, dry element, the seal, the breather assembly, and the clamp.
6. Install the hose and the hose clamp; refer to SENR3130 for torques.

⚠ Hot oil and hot components can cause personal injury.

⚠ Do not fill the oil filters with oil before installing them.

⚠ Do not crank the engine for more than 30 seconds.

Tools: 1U-8760 Chain Wrench, 175-7546 Oil Filter Cutter Gp

1. Run the engine at normal operating temperature, then stop the engine.
2. Drain the crankcase through the drain valve or the oil drain plugs.
3. Remove the oil filter with a 1U-8760 Chain Wrench.
4. Cut the filter open with a 175-7546 Oil Filter Cutter Gp; inspect for debris.
5. Clean the filter mounting base sealing surface; remove all old gasket.
6. Apply clean engine oil to new filter gasket; install filter hand tight.
7. Fill crankcase between the ADD mark and the FULL mark on the gauge.
8. Run engine at low idle two minutes; inspect filter for leaks; check level.

⚠ Wear protective glasses or face shield and protective clothing to prevent burns.

⚠ An improperly operating valve rotator will accelerate valve face and valve seat wear.

1. Perform after the engine valve lash is set, before valve covers are installed.
2. Start the engine according to Engine Starting procedure.
3. Operate the engine at low idle.
4. Observe the top surface of each valve rotator.
5. The valve rotators should turn slightly when the valves close.
6. If a valve fails to rotate, consult your Caterpillar dealer.