Volvo Penta TD720GE Engine

⚠ Adjustments must be made by a qualified engineer.

⚠ Do not set voltage if frequency or speed is incorrect.

1. Install DC voltmeter on E+ and E- and AC voltmeter on alternator output.
2. Set strap ST3 to desired frequency, 50 or 60 Hz.
3. Set voltage potentiometer P2 fully anti-clockwise.
4. Turn V/Hz potentiometer P4 fully clockwise.
5. Set stability potentiometer P3 approximately 1/3 anti-clockwise turn.
6. Start engine and set speed to 48 Hz for 50 Hz or 58 Hz for 60 Hz.
7. Adjust output voltage to rated value with P2.
8. If voltage oscillates, adjust P3; try normal or fast response via ST2.
9. Check LAM operation with ST5 closed.
10. Turn P4 slowly anti-clockwise until voltage drops approximately 15%.
11. Vary frequency around 48 or 58 Hz and check voltage change.
12. Readjust speed to rated no-load value.

⚠ Only tighten the stop screw gently by hand.

Tools: Measuring fixture 999 8684, Rule depth gauge 998 5471, Pressure tool 999 8682

1. Turn the engine through 180° and attach measuring fixture 999 8684 on the leading edge of the engine.
2. Measure from the measuring fixture to the control rod stop position with rule depth gauge 998 5471.
3. Measure from the measuring fixture to the control rod start position.
4. The difference between start and stop positions is the control rod travel.
5. Turn the measuring fixture and push the control rod to the stop position by hand using the stop screw.

⚠ TD420VE, TAD420VE and TAD620VE fan belts have automatic tensioner and need no adjustment

1. Inspect and adjust after operation when belts are hot
2. Loosen the screws (A) before tensioning the alternator belts
3. Adjust so belts can be pressed down about 10 mm between pulleys
4. Change worn belts which operate in pairs together
5. Check condition of drive belts, change as necessary

⚠ Fuel pressure jet can penetrate deep into skin tissue and cause blood poisoning.

⚠ Use only clean test oil meeting ISO 4113 or clean diesel.

Tools: Nozzle tester, Injector microscope, Ultrasonic cleaner

1. Connect the injector to the nozzle tester.
2. Check the opening pressure; control value in Technical data.
3. Check leak-down: pressure may at most drop to 5 MPa / 5 sec.
4. Hold 2 MPa below opening pressure for 10 s; no drips permitted.
5. Take off the cap nut and remove all parts.
6. Wash details in an ultrasonic cleaner or washing petrol/Vanolen.
7. Inspect injector details using an injector microscope.
8. Dip parts in oil before assembly.
9. Set pressure by selecting an appropriate shim; thicker shim increases opening pressure.
10. Tighten the cap nut to 40 ±5 Nm and recheck in the nozzle tester.
11. Check seal and perform chatter characteristic / spray pattern test.

Tools: Feeler gauge, Rotating tool 999 8676, Cranking tool 999 8681

1. Set valve clearance with the engine cold or cooled at least half an hour (oil temp < 80 °C).
2. Rotate the crankshaft until the valves of cylinder 1 overlap.
3. Set the valve clearance for each cylinder with a feeler gauge per the black markings.
4. Inlet 0.35 ±0.05 mm; exhaust 0.55 ±0.05 mm.
5. Tighten the locknut to 20 ±2 Nm and recheck with the feeler gauge.
6. Rotate the crankshaft another 360° and repeat for the remaining cylinders.
7. Fit a new rocker cover gasket.

⚠ Make sure that the fuel control rod is in the no fuel position (stop position).

Tools: Adapter 999 8694, Compression gauge 998 8539

1. The injectors must be removed and the valve clearance checked.
2. Fit adapter 999 8694, using the existing injector yoke.
3. Tighten the screw to 19 ±2 Nm.
4. Connect the compression tester 998 8539.
5. Turn the engine over with the starter motor.
6. Make sure the fuel control rod is in the no-fuel (stop) position.
7. Compare cylinders; dismantle the cylinder if the pressure difference exceeds 15%.

⚠ The injectors are sensitive and may easily be damaged by contamination.

Tools: Manometer 999 6398, Nipple 999 6066, Hollow screw 180211, Copper washer 969011, Electrical pressure gauge 999 8496, Hose 999 8493

1. Clean the nipple and hose thoroughly before connecting them.
2. Check the fuel pump and replace if necessary.
3. Measure the supply pressure before (1) and after (2) the fuel filter.
4. Use manometer 999 6398, nipple 999 6066 with hollow screw 180211 and new copper washers 969011.

Tools: Manometer 999 6398, Nipple 999 6066, Spacer 1678297, Electrical pressure gauge 999 8496, Hose 999 8493

1. Measure the lubricating oil pressure on the starter motor side of the engine.
2. Use the manometer together with nipple and spacer.
3. Compare the reading with the minimum oil pressure at operating temperature and idle speed.

⚠ The oil cooler may not be repaired.

⚠ The oil cooler should be the same temperature as the surroundings during the check.

Tools: Pressure-testing equipment 999 6662, Clamp for cooler 999 6685, Plug M26x1.5 942352

1. Place a clamp on the oil cooler and make sure it is properly tightened.
2. Plug the other connection.
3. Connect the pressure-testing equipment.
4. Place the oil cooler in a tub of water.
5. Set the air pressure to 100 kPa and check for air bubbles.
6. Increase the pressure to 500 kPa and hold for 1 minute; pressure may not drop.
7. If pressure drops there is a leak and the oil cooler must be replaced.

⚠ Never allow open flame or electric sparks near battery.

⚠ Battery electrolyte contains corrosive sulphuric acid.

1. Keep battery dry and clean.
2. Clean terminals and leads with a brass brush to remove oxidation.
3. Tighten cable terminals and grease with terminal grease or petroleum jelly.
4. Electrolyte should be 5-10 mm over plates.
5. Top up with distilled water if necessary.
6. Charge battery after topping up for at least 30 minutes by running engine at fast idle.
7. Connect red positive lead first, then black negative lead.
8. When disconnecting, disconnect negative lead first, then positive lead.

⚠ Battery electrolyte is highly corrosive

⚠ Fire and explosion hazard

Tools: Copper brush, Protective goggles and gloves

1. Keep batteries dry and clean; clean oxidation from poles with a copper brush
2. Tighten terminals securely and grease with terminal grease or Vaseline
3. Electrolyte level 5-10 mm (0.2-0.4 in) above cell plates
4. Top up with distilled water as necessary
5. After filling, charge battery at least 30 minutes by running engine at fast idle

⚠ Anti-corrosion mixture does not offer any protection against frost; if risk of frost, system must be drained

Tools: Volvo Penta original paint

1. Change engine oil and oil filter
2. Change the fuel filter; also change the primary fuel filter if fitted
3. Warm the engine up
4. Check coolant offers sufficient frost protection, top up as necessary
5. Drain water and contamination from fuel tank; fill fuel tank completely
6. Clean outside of engine; do not use a power washer
7. Disconnect, clean and charge the batteries
8. Spray electrical system components with water-repellent spray