Isuzu 4LE2 Generator Set

1. Check cooling fan drive belt for cracking and other damage.
2. Check belt tension by exerting 98 N (10 kg) midway between fan pulley 1 and generator pulley 2.
3. Loosen generator mounting bolt and generator adjusting bolt and pivot the generator to adjust tension.
4. Retighten the bolts after adjusting belt tension.

⚠ Check and adjust fan belt tension with engine stopped

1. Loosen the alternator adjusting plate bolt and the alternator mounting bolt.
2. Pivot the alternator at the mounting bolt by adjusting the adjusting bolt.
3. Tighten the mounting bolt and the adjusting bolt.
4. Operate the engine about five minutes at low idle speed and recheck belt tension.

⚠ Follow the instructed order to tighten bolts.

⚠ Do not retighten if you tighten by the angle method.

⚠ Check the mark to confirm you tightened the bolt to the specified angle; otherwise you may re-tighten by angle method and damage the bolt.

Tools: Bolt angle gauge (5-8840-0266-0)

1. Apply molybdenum disulfide or engine oil to the threads and the seating surface of the bolt following the instruction.
2. Tighten all bolts to the pre-indicated tightening torque.
3. Draw lines on the surface of the parts you tighten: lines through the bolt's center (A-B bolt side, C-D parts side) and the line at the specified tightening angle from the bolt's center (E-F).
4. Tighten the bolt with wrench until the line on the bolt (A-B) aligns with the specified angle line (E-F on the surface of the parts).

⚠ Take care to avoid entry of dust or foreign particles into the pump interior when the timing adjustment is made.

1. Remove injection pipe of No. 1 cylinder.
2. Remove delivery valve holder of No. 1 cylinder injection pump and pull out delivery spring.
3. With spring removed, install the delivery valve holder.
4. Slowly turn crankshaft pulley clockwise while feeding fuel; stop when fuel stops flowing from No. 1 delivery valve holder.
5. Confirm degree of crank pulley groove mark against timing mark on timing gear case.
6. Adjust injection timing with a shim between injection pump and cylinder block if out of range.

⚠ Do not move the connecting rod while using the plastigauge.

Tools: Plastigauge

1. Clean the connecting rod and bearing, and install the bearing to the rod.
2. Cut the plastigauge to the same width as the crank pin, and lay the gauge parallel to the pin avoiding the oil hole.
3. Line up the marks on the connecting rod and cap and install the crank pin.
4. Apply molybdenum disulfide to the thread section and seating surface of the tightening bolt, and rotate both cap and bolt to the correct torque.
5. Gently remove the cap and connecting rod, and measure the crushed width of the plastigauge using the scale printed on the bag.

⚠ Do not rotate the crankshaft while using the plastigauge.

Tools: Plastigauge

1. Clean the clamp face of the cylinder block and crankcase bearing, and also the bearing, and install the cylinder block to the crankcase.
2. Gently rest the crankshaft on the cylinder block, and rotate it approximately 30 degrees to stabilize it.
3. Cut the plastigauge to the same size as the journal width, and lay the gauge parallel to the journal avoiding the oil hole.
4. Gently rest the crankcase on the cylinder block, apply molybdenum disulfide to the thread section and seating surface of the tightening bolt, and tighten in sequence to the correct torque.
5. Gently remove the crankcase, and measure the crushed width of the plastigauge using the scale printed on the bag.

Tools: Feeler gauge

1. Bring No. 1 or No. 3 piston to TDC on compression stroke (align TDC mark with pulley groove mark).
2. Check for play in No. 1 intake and exhaust valve rocker arms to confirm compression stroke.
3. Loosen each valve clearance adjusting screw.
4. Insert a 0.40 mm (0.015 in) feeler gauge between rocker arm and valve stem end.
5. Turn adjusting screw until slight drag is felt on feeler gauge.
6. Tighten lock nut securely.
7. Rotate crankshaft 360° and realign crankshaft pulley.
8. Adjust clearances for remaining valves as shown in the illustration.

⚠ The rocker arm is die-cast aluminum; do not tighten the adjusting screw to excess

1. Turn the crankshaft clockwise so the mark groove on the crank pulley aligns with the TDC mark on the timing gear case cover.
2. Remove the cylinder head cover and check if cylinder No.1 is at TDC in the compression stroke.
3. Measure and adjust the clearance of the valves marked for the condition of cylinder No.1.
4. Turn the crankshaft in normal direction to align marks again, then measure and adjust the other valves.

Tools: Compression Gauge 5-8840-2675-0, Compression Gauge Adapter 5-8840-9029-0

1. Operate engine to warm up until coolant temperature reaches 75°C (167°F).
2. Remove all glow plugs and injection pipes.
3. Attach compression gauge to No. 1 cylinder glow plug installation threads.
4. Crank engine with starter motor and take compression gauge reading.
5. Repeat for remaining cylinders.

⚠ Use the correct quantity of liquid gasket; always follow the handling instructions for each product.

⚠ Do not use gasket remover (Pando-391D) on resin components or painted components.

1. Wipe the contact surfaces clean of all water, oil or grease. The contact surfaces should be dry.
2. Apply a regular bead width of liquid gasket to one of the contact surfaces. Make sure that the bead does not break at this point.
3. If there are special regulations concerning the application procedure in the repair document, follow those regulations.

⚠ Cover the radiator cap with a rag and turn slowly to release steam pressure when engine is hot

1. Remove the radiator cap.
2. Open the drain cock at the radiator lower part to drain coolant.
3. Drain coolant from the engine via the water drain plug at the rear of alternator on the left side of cylinder body.
4. Close or tighten the coolant drain plug.
5. Fill the radiator with clean drinking water up to the filler port neck, gradually to prevent air entry.
6. Operate the engine about five minutes at low idle speed to bleed air, then stop and replenish coolant.

⚠ Do not drain oil while the engine is still hot

Tools: filter wrench

1. Wipe clean around the oil filler cap and remove it.
2. Remove the oil pan drain plug and drain the engine oil completely.
3. Use a filter wrench to remove the cartridge type oil filter element.
4. Apply lightly engine oil to the O-ring of the new cartridge.
5. Turn in new cartridge until its sealed face contacts the O-ring.
6. Turn the cartridge in a further 3/4 turn with a filter wrench.
7. Reinstall the drain plug and fill with new engine oil by the oil filler port.
8. Wait about fifteen minutes and check the oil level with the dipstick.