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MTU 20V 4000 Gx3 Engine

Name: MTU 20V 4000 Gx3 Engine
Brand: MTU

The MTU 20V 4000 Gx3 is a 95.4 L 20-cylinder exhaust turbocharging (etc) and charge air cooling (cac) engine. It holds 390 L (103.0 gal) of oil and 205 L (54.2 gal) of coolant.

Also known as: MTU 20V 4000 Gx3

Part of the MTU 20V4000 engine family — 59 variants share parts & fitment.

95.4 L

Displacement

Cylinders

390.0 L

Oil capacity

On this pageSpecs Maintenance FAQ Service intervals Torque & specs Fluids Fault codes Procedures

Engine specifications

Oil capacity	390.0 L
Coolant capacity	205.0 L
Displacement	95.4 L
Cylinders	20
Aspiration	Exhaust turbocharging (ETC) and charge air cooling (CAC)

Generator sets

No generator set in our catalog cites this exact engine designation yet; its specifications and fault codes are documented here.

How to read your MTU engine serial & model number →

Troubleshooting

Fault codes

Code	Meaning	Remedy
99	Lube-oil temperature before engine, shutdown
101	Lube-oil temperature before engine, shutdown
401	Lube oil pressure before engine, shutdown
SEO03	Nd11 231	Contact Service.
003	HI T-Fuel	Contact Service.
004	SS T-Fuel	Contact Service.
005	HI T-Charge Air	1. Reduce power, 2. Check intercooler.
006	SS T-Charge Air	1. Reduce power, 2. Check intercooler.
009	HI T-Coolant Intercooler	Reduce power.
010	SS T-Coolant Intercooler	Reduce power.
015	LO P-Lube Oil
016	SS P-Lube Oil	1. Check oil level, top up as necessary (> Page 169). 2. Attempt to restart engine (-» Page 55).
019	HI T-Exhaust A	1. Check cabling (— Page 194). 2. Contact Service.
020	SS T-Exhaust A	1. Check cabling (— Page 194). 2. Contact Service.
021	HI T-Exhaust B	1. Check cabling (— Page 194). 2. Contact Service.
022	SS T-Exhaust B	1. Check cabling (> Page 194). 2. Contact Service.
023	LO Coolant Level	Check coolant level in expansion tank (— Page 176).
025	HI P-Diff Lube Oil	Replace oil filter (— Page 173).
026	HI P-Diff Lube Oil	Replace oil filter (— Page 173).
027	HI Leak Fuel Level	1. Check fuel system. 2. Contact Service.
029	HI ETC 2 idle speed	Contact Service.
030	SS Engine Speed	1. Acknowledge alarm. 2. Attempt to restart engine.
031	HI ETC 1 overspeed	Contact Service.
032	SS ETC 1 overspeed	1. Automatic power reduction by engine control system. 2. Check air filters (— Page 164).
033	HI P-Diff-Fuel	Replace fuel filter (— Page 153).
034	SS P-Diff-Fuel	Replace fuel filter (— Page 153).
036	HI ETC 2 Overspeed	1. Reduce power. 2. Contact Service.
037	SS ETC 2 Overspeed	1. Reduce power. 2. Contact Service.
038	AL ETC Speed Deviation	1. Reduce power. 2. Contact Service.
039	AL ETC 2 Cutin Failure	1. Reduce power. 2. Contact Service.
044	LO Coolant Level Intercooler	Check coolant level (— Page 184).
051	HI T-Lube Oil	Reduce power.
052	SS T-Lube Oil	1. Reduce power. 2. Check engine oil level (— Page 169).
057	LO P-Coolant	Check coolant circuit.
058	SS P-Coolant	1. Automatic engine shutdown. 2. Check coolant level (— Page 176).
059	SS T-Coolant L3	1. Allow engine to cool down; 2. Check coolant cooler, clean if necessary; 3. Contact Service.
060	SS T-Coolant L4	1. Allow engine to cool down; 2. Check coolant cooler, clean if necessary; 3. Contact Service.
063	HI P-Crankcase	1. Reduce power. 2. Replace oil separator element (— Page 138).
064	SS P-Crankcase	1. Replace oil separator element (— Page 138). 2. Contact Service.
065	LO P-Fuel	Clean fuei prefilter (— Page 154). Flush fuel prefiiter (+ Page 158). Replace filter element of fuel prefilter (> Page 160). Replace fuel filter (=> Page 153).
066	SS P-Fuel	Clean fuei prefilter (— Page 154). Flush fuel prefiiter (+ Page 158). Replace filter element of fuel prefilter (> Page 160). Replace fuel filter (=> Page 153).
067	Hi T-Coolant	Reduce power.
068	SS T-Coolant	1. Allow engine to cool down; 2. Check coolant cooler, clean if necessary; 3. Restart engine (— Page 59). 4. Contact Service.
081	AL Rail Leakage	Contact Service.
082	HI P-Fuel (Common Rail)	Contact Service.
083	LO P-Fuel (Common Rail)	Contact Service.
085	HI T-Recirculation	Reduce power.
086	HI T-Recirculation	Reduce power.
089	SS Engine Speed too Low	Check for additional messages.
090	SS Starter Speed Not Reached	Contact Service.
091	SS Release Speed Not Reached	Contact Service.
092	SS Starter Speed Not Reached	Contact Service.
093	SS T-Preheat	Check preheater.
094	LO T-Preheat	Check preheater.
095	AL Prelubrication Fault	Check oil priming system.
102	AL Consumption Meter Faulty	Contact Service.
104	AL Eng Hours Counter Defect	Contact Service.

Fault codes and symptom→remedy steps extracted from this engine’s service/owner documentation; verify against the official manual before servicing.

Common problems

SS Starter Speed Not Reached 090
Fix: Contact Service.
Lube-oil temperature before engine, shutdown 99
HI T-Recirculation 085
Fix: Reduce power.
Tripped by crash recorder triggering due to engine shutdown. 475
Fix: Determine and rectify cause of triggering / engine shutdown.
Temperature signal of Aux 1 has exceeded / not attained limit value 2, depending on configuration. 467 - AL L2 T-Aux 1
Fix: Determine and rectify reason for limit value violation.
Temperature sensor for ECU faulty; short circuit or wire break. 470
Fix: Check sensor and cabling, replace as necessary. Error cleared after restarting the engine.
SS T-Preheat 093
Fix: Check preheater.
SS T-Lube Oil 052
Fix: Reduce power. Check engine oil level (— Page 169).
SS T-Coolant L4 060
Fix: Allow engine to cool down; Check coolant cooler, clean if necessary. Contact Service.
SS T-Coolant L3 059
Fix: Allow engine to cool down; Check coolant cooler, clean if necessary. Contact Service.
SS T-Coolant 068
Fix: Allow engine to cool down; Check coolant cooler, clean if necessary. Restart engine (— Page 59) Contact Service.
SS Release Speed Not Reached 091
Fix: Contact Service.
SS P-Fuel 066
Fix: Check fuel lines for leaks. Clean fuel prefilter (— Page 154). Flush fuel prefilter (—+ Page 158). Replace filter element of fuel prefilter (— Page 160). Replace fuel filter (=> Page 153).
SS P-Diff-Fuel 034
Fix: Replace fuel filter (— Page 153).
SS P-Crankcase 064
Fix: Replace oil separator element (— Page 138). Contact Service.

Compiled from service & troubleshooting documentation across every generator set that uses the MTU 20V 4000 Gx3.

Maintenance schedule

Item	Spec	Part #	Interval
Air filter	Replace air filter	—	6000 hr
Fuel filter	Replace fuel filter or fuel filter element	—	5000 hr
Oil filter	Replace engine oil filter every time oil is changed, latest when year limit is reached	F30379104	2 hr	Amazon eBay $371.15
Belt	Check condition of drive belt, replace as necessary; adjust tension	—	3000 hr
Coolant filter		—
Oil		F30027337	100 hr	Amazon eBay
Spark plug		—

Pooled from every document that names this exact engine — confirm the interval and part number against your unit's serial number.

Repair guides

Drive Belt Condition Check

Step-by-step procedures compiled from the MTU service manual for this engine.

Service intervals

Item	Action	Hours	Months	Notes
Centrifugal oil filter	Clean	500 hr	24 mo	Check oil residue layer thickness, clean, replace filter sleeve
Fuel filter	Replace	1000 hr	24 mo	Replace fuel filter or fuel filter element
Valve gear	Check	1000 hr		Check valve clearance
Belt drive	Check	1600 hr	24 mo	Check condition of drive belt, replace as necessary; adjust tension
Air filter	Replace	3000 hr	36 mo
Cylinder chambers	Inspect	5000 hr	48 mo	Endoscope cylinder chambers
Fuel injectors	Replace	5000 hr
Exhaust turbocharger	Other	6000 hr		3D application group: overhaul exhaust turbochargers
Component maintenance	Other	10000 hr		Drain coolant and flush coolant circuits; clean air line; clean intercooler and check leak-tightness; replace HP fuel sensor; check engine coolant thermostat and replace thermostat element; check charge-air coolant thermostat and replace thermostat element; check centrifugal oil filter for wear; overhaul starter; overhaul charge-air coolant pump; replace sealing materials on all dismantled components; overhaul engine coolant pump; check vibration dampers; overhaul engine coolant preheater
Crankcase breather	Replace	10000 hr		Replace filter or filter element
Cylinder head	Other	10000 hr		Overhaul cylinder heads
Extended component maintenance	Other	10000 hr	18 mo	Dismantle engine completely; inspect engine components; replace all elastomer parts and seals; replace piston rings; replace conrod bearings; replace crankshaft bearings; replace cylinder liners; replace auxiliary PTO antifriction bearings; replace HP fuel pump; overhaul battery-charging generator
Fuel delivery pump	Replace	10000 hr
Engine oil filter	Replace		24 mo	Replace every time oil is changed, latest when year limit is reached
Engine operation	Test		1 mo	Perform test run, min. duration until steady-state temperature reached, not below 1/3 load (monthly)

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Service specifications

Type	Item	Value	Unit	Condition
Clearance	Valve clearance deviation requiring adjustment	0.1	mm	exceeds reference value
Other	Coolant antifreeze content, max.	50	%
Other	Engine weight, dry	9640	kg	basic engine configuration
Other	Main engine height (C)	2490	mm	approx.
Other	Main engine length (A)	3520	mm	approx.
Other	Main engine width (B)	1620	mm	approx.
Other	Permissible coolant discharge, engine coolant pump relief bore	10	drops/hour
Other	Permissible oil discharge, engine coolant pump relief bore	5	drops/hour
Other	Site altitude above sea level reference	100	m
Pressure	Barometric pressure reference	1000	mbar
Pressure	Charge air pressure before cylinder, BL	2.5 to 3.6	bar abs	varies by model
Pressure	Final compression pressure at 120 rpm	24 to 28	bar	at 120 rpm
Pressure	Fuel prefilter differential pressure flush limit	0.3	bar	flush filter element if differential pressure >=
Pressure	Fuel pressure at engine inlet connection, max during starting	1.5	bar
Pressure	Fuel pressure at engine inlet connection, min during starting	-0.1	bar
Pressure	Lube-oil operating pressure before engine, from	4.5 to 5.0	bar	varies by model
Pressure	Lube-oil operating pressure before engine, to	7.3 to 7.8	bar	varies by model
Speed	Firing speed, from	80	rpm
Speed	Firing speed, to	120	rpm
Temperature	Cold start capability air temperature (w/o start aid, w/o preheating)	10	°C	case A
Temperature	Coolant preheating temperature (min.)	32	°C
Temperature	Coolant temperature after engine, alarm	102	°C
Temperature	Coolant temperature after engine, shutdown	104	°C
Temperature	Coolant temperature before intercooler (LT circuit)	45	°C	at engine inlet from cooling equipment
Temperature	Intake air temperature reference	25	°C
Temperature	Lube-oil temperature before engine, alarm	99	°C
Temperature	Lube-oil temperature before engine, shutdown	101	°C
Torque	Battery-charging generator drive belt screw (1)	42	Nm
Torque	Battery-charging generator drive belt screw (2)	60 to 65	Nm
Torque	Centrifugal oil filter clamp	8 to 10	Nm
Torque	Centrifugal oil filter cover nut	5 to 7	Nm
Torque	Centrifugal oil filter rotor cover nut	35 to 45	Nm
Torque	Crankcase breather cover screw	10	Nm	tolerance -2 Nm, lubricant engine oil
Torque	Injector adapter preload	5 to 10	Nm	engine oil
Torque	Injector adapter tightening	100	Nm	tolerance +10 Nm
Torque	Injector hold-down screw M12 preload	5 to 10	Nm	engine oil
Torque	Injector hold-down screw M12 tightening	100	Nm	tolerance +10 Nm
Torque	Jacketed HP fuel line union nut / thrust screw	40	Nm	tolerance +5 Nm
Torque	Nuts (6) on screws (5) transport locking device	30	Nm	tolerance +3 Nm, lubricant engine oil
Torque	Oil drain plugs (2),(3)	100	Nm	tolerance +10 Nm
Torque	Screws (2),(8) plates (1) transport locking device	250	Nm	tolerance +25 Nm, lubricant engine oil
Torque	Single-walled HP fuel line union nut / thrust screw	30	Nm	tolerance +5 Nm
Torque	Valve clearance locknut	90	Nm	tolerance +9 Nm
Valve clearance	Exhaust valves (short rocker arm)	0.5	mm	cold
Valve clearance	Inlet valves (long rocker arm)	0.2	mm	cold

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Recommended fluids

Fluid	Grade	Standard	Capacity	Notes
Coolant		MTU Fluids and Lubricants Specifications A001061/..	205.0 liters	Engine coolant capacity, engine side (without cooling equipment)
Engine oil		MTU Fluids and Lubricants Specifications A001061/..	390.0 liters	Total engine oil capacity at initial filling (standard oil system); oil pan capacity at dipstick mark min 245 L, max 340 L
Fuel	Diesel fuel	MTU Fluids and Lubricants Specifications A001061/..		Fuel pressure at engine inlet connection min -0.1 bar, max 1.5 bar during engine starting

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Fault codes

Code	Name	Meaning	Severity	Action
003	HI T-Fuel	Fuel temperature too high	Warning	Contact Service.
004	SS T-Fuel	Fuel temperature too high; engine shutdown	Shutdown	Contact Service.
005	HI T-Charge Air	Charge-air temperature too high	Warning	Reduce power; check intercooler.
006	SS T-Charge Air	Charge-air temperature too high; engine shutdown	Shutdown	Reduce power; check intercooler.
009	HI T-Coolant Intercooler	Coolant temperature in intercooler too high	Warning	Reduce power.
010	SS T-Coolant Intercooler	Coolant temperature in intercooler too high; engine shutdown	Shutdown	Reduce power.
015	LO P-Lube Oil	Lube oil pressure too low	Warning	Check oil level, top up as necessary.
016	SS P-Lube Oil	Lube oil pressure too low; engine shutdown	Shutdown	Check oil level, top up as necessary; attempt to restart engine.
019	HI T-Exhaust A	Exhaust gas temperature (A-side) too high	Warning	Check cabling; contact Service.
020	SS T-Exhaust A	Exhaust gas temperature (A-side) too high; engine shutdown	Shutdown	Check cabling; contact Service.
021	HI T-Exhaust B	Exhaust gas temperature (B-side) too high	Warning	Check cabling; contact Service.
022	SS T-Exhaust B	Exhaust gas temperature (B-side) too high; engine shutdown	Shutdown	Check cabling; contact Service.
023	LO Coolant Level	Coolant level too low	Warning	Check coolant level in expansion tank.
025	HI P-Diff. Lube Oil	Oil filter differential pressure too high	Warning	Replace oil filter.
026	HI P-Diff. Lube Oil Limit 2	Oil filter differential pressure too high	Warning	Replace oil filter.
027	HI Leak Fuel Level	Leak-fuel level too high	Warning	Check fuel system; contact Service.
030	SS Engine Speed	Reduced fuel injection	Shutdown	Acknowledge alarm; attempt to restart engine.
031	HI ETC 1 overspeed	Speed of primary turbocharger too high	Warning	Contact Service.
032	SS ETC 1 overspeed	Speed of primary turbocharger too high	Shutdown	Automatic power reduction by engine control system; check air filters.
034	SS P-Diff-Fuel	Fuel filter differential pressure too high	Shutdown	Replace fuel filter.
051	HI T-Lube Oil	Lube oil temperature too high	Warning	Reduce power.
052	SS T-Lube Oil	Lube oil temperature too high; engine shutdown	Shutdown	Reduce power; check engine oil level.
057	LO P-Coolant	Coolant pressure too low	Warning	Check coolant circuit.
058	SS P-Coolant	Coolant pressure too low; engine shutdown or reduction of fuel injection	Shutdown	Automatic engine shutdown; check coolant level.
063	HI P-Crankcase	Crankcase pressure too high	Warning	Reduce power; replace oil separator element.
064	SS P-Crankcase	Crankcase pressure too high; engine shutdown	Shutdown	Replace oil separator element; contact Service.
065	LO P-Fuel	Fuel supply pressure too low	Warning	Check fuel lines for leaks; clean fuel prefilter; flush fuel prefilter; replace filter element of fuel prefilter; replace fuel filter.
066	SS P-Fuel	Fuel supply pressure too low; engine shutdown	Shutdown	Check fuel lines for leaks; clean fuel prefilter; flush fuel prefilter; replace filter element of fuel prefilter; replace fuel filter.
067	HI T-Coolant	Coolant temperature too high	Warning	Reduce power.
068	SS T-Coolant	Coolant temperature too high; engine shutdown	Shutdown	Allow engine to cool down; check coolant cooler, clean if necessary; restart engine; contact Service.
081	AL Rail Leakage	Pressure gradient in common rail too low during engine start or too high during engine stop; HP fuel system leaky, air in system	Warning	Contact Service.
082	HI P-Fuel (Common Rail)	Rail pressure > set-point value; DBR reduction, start of injection moved to late; suction restrictor jamming or wiring of suction restrictor faulty	Warning	Contact Service.
083	LO P-Fuel (Common Rail)	Rail pressure > set-point value; DBR reduction, suction restrictor faulty or leak in HP fuel system	Warning	Contact Service.
089	SS Engine Speed too Low	Engine speed too low	Shutdown	Check for additional messages.
090	SS Starter Speed Not Reached	Idling speed was not attained	Shutdown	Contact Service.
091	SS Release Speed Not Reached	Runup speed was not attained	Shutdown	Contact Service.
092	SS Starter Speed Not Reached	Starter speed was not attained; termination of start sequence; starter rotates too low or not at all	Shutdown	Contact Service.
093	SS T-Preheat	Preheating temperature too low; coolant temperature too low for engine start; engine start interlock	Shutdown	Check preheater.
094	LO T-Preheat	Preheating temperature too low; coolant temperature too low for engine start	Warning	Check preheater.
095	AL Prelubrication Fault	Oil priming failure	Warning	Check oil priming system.
118	LO ECU Supply Voltage	Supply voltage too low	Warning	Check ECU supply voltage; contact Service.
119	LOLO ECU Supply Voltage	Supply voltage too low	Shutdown	Check ECU supply voltage; contact Service.
120	HI ECU Supply Voltage	Supply voltage too high	Warning	Check ECU supply voltage; contact Service.
121	HIHI ECU Supply Voltage	Supply voltage too high	Shutdown	Check ECU supply voltage; contact Service.
122	HI T-ECU	Electronic unit temperature too high	Warning	Reduce power; improve engine room ventilation.
201	SD T-Coolant	Coolant temperature sensor faulty; short circuit or wire break	Warning	Check sensor and cabling (B6), replace as necessary. Error cleared after restarting the engine.
202	SD T-Fuel	Fuel temperature sensor faulty; short circuit or wire break	Warning	Check sensor and cabling (B33), replace as necessary. Error cleared after restarting the engine.
203	SD T-Charge Air	Charge-air temperature sensor faulty; short circuit or wire break	Warning	Check sensor and cabling (B9), replace as necessary. Error cleared after restarting the engine.
204	SD Level Lube Oil	Lube-oil level sensor faulty; short circuit or wire break	Warning	Check sensor and cabling, replace as necessary.
205	SD T-Coolant Intercooler	Coolant temperature sensor of intercooler faulty; short circuit or wire break	Warning	Check sensor and cabling (B26), replace as necessary. Error cleared after restarting the engine.
206	SD T-Exhaust A	Exhaust temperature sensor on A-side faulty; short circuit or wire break	Warning	Check sensor and cabling (B4.21), replace as necessary. Error cleared after restarting the engine.
207	SD T-Exhaust B	Exhaust temperature sensor on B-side faulty; short circuit or wire break	Warning	Check sensor and cabling (B4.22), replace as necessary. Error cleared after restarting the engine.
208	SD P-Charge Air	Charge-air pressure sensor faulty; short circuit or wire break	Warning	Check sensor and cabling (B10), replace as necessary. Error cleared after restarting the engine.
211	SD P-Lube Oil	Lube-oil pressure sensor faulty; short circuit or wire break	Warning	Check sensor and cabling (B5), replace as necessary. Error cleared after restarting the engine.
212	SD P-Coolant	Coolant pressure sensor faulty; short circuit or wire break	Warning	Check sensor and cabling (B16), replace as necessary. Error cleared after restarting the engine.
213	SD P-Coolant Intercooler	Coolant pressure sensor of intercooler faulty; short circuit or wire break	Warning	Check sensor and cabling (B43), replace as necessary. Error cleared after restarting the engine.
214	SD P-CrankCase	Crankcase pressure sensor faulty; short circuit or wire break	Warning	Check sensor and cabling (B50), replace as necessary. Error cleared after restarting the engine.
215	SD P-HD	Rail pressure sensor faulty; HP fuel regulator in emergency mode; short circuit or wire break	Warning	Check sensor and cabling (B48), replace as necessary. Error cleared after restarting the engine.
216	SD T-Lube Oil	Lube-oil temperature sensor faulty; short circuit or wire break	Warning	Check sensor and cabling (B7), replace as necessary. Error cleared after restarting the engine.
219	SD T-Intake Air	Intake air temperature sensor faulty; short circuit or wire break	Warning	Check sensor and cabling (B3), replace as necessary. Error cleared after restarting the engine.
220	SD Coolant Level	Coolant level sensor faulty; short circuit or wire break	Warning	Check sensor and cabling (F33), replace as necessary. Error cleared after restarting the engine.
230	SD Crankshaft Speed	Crankshaft speed sensor faulty; short circuit or wire break	Warning	Check sensor and cabling (B13), replace as necessary. Error cleared after restarting the engine.
231	SD Camshaft Speed	Camshaft speed sensor faulty; short circuit or wire break	Warning	Check sensor and cabling (B1), replace as necessary. Error cleared after restarting the engine.
245	SD ECU Supply Voltage	Internal ECU fault; electronic block faulty	Shutdown	Replace ECU.
301	AL Timing Cylinder A1	Time-of-flight measuring fault of injector: time-of flight measured value extremely low or extremely high	Warning	Replace injector concerned if the fault message appears frequently.
321	AL Wiring Cylinder A1	Cabling fault in injector cabling to cylinder. Result: misfiring	Warning	Check solenoid valve; contact Service.
341	AL Open Load Cylinder A1	Disruption fault in injector cabling to cylinder. Result: misfiring	Warning	Check solenoid valve; contact Service.
361	AL Power Stage Low	Internal electronic fault (electronics possibly faulty: start ITS)	Warning	Check solenoid valve cabling; replace ECU.
362	AL Power Stage High	Internal electronic fault (electronics possibly faulty: start ITS)	Warning	Check solenoid valve cabling; replace ECU.
363	AL Stop Power Stage	Internal electronic fault (electronics possibly faulty: start ITS)	Shutdown	Check cabling; attempt to restart engine.
365	AL Stop MV-Wiring Ground	Injector cabling fault. Short circuit of positive or negative connection of one or more injectors to ground	Shutdown	Check cabling; attempt to restart engine.
414	HI Water Level Fuel Prefilter	Water level in fuel prefilter too high	Warning	Drain water.
415	LO P-Coolant Intercooler	Coolant pressure in intercooler too low	Warning	Top up coolant.
416	SS P-Coolant Intercooler	Coolant pressure in intercooler too low; engine shutdown	Shutdown	Top up coolant.
417	SD Water Level Fuel Prefilter	Water level sensor of fuel prefilter faulty; short circuit or wire break	Warning	Check sensor and cabling, replace as necessary. Error cleared after restarting the engine.
448	HI P-Charge Air	Charge-air pressure too high	Warning	Contact Service.
449	SS P-Charge Air	Charge-air pressure too high	Shutdown	Contact Service.
454	SS Power Reduction Active	Power reduction is active	Shutdown	Note further fault messages; determine and rectify reason for power reduction.
510	AL Override applied	Override was activated	Warning	Deactivate Override pushbutton.
519	Oilniveau Calibration Error	Error when writing the calibration value to flash memory or level sensor defect	Warning	Check sensor and cabling, replace as necessary; contact Service.

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Procedures

Valve clearance — Check and adjustment adjustment

Tools: Feeler gauge Y20010128, Torque wrench 60-320 Nm F30047446, Ring socket 24 mm F30039526

Remove cylinder head cover.
Install barring tool.
Rotate crankshaft until marking OT-A1 and pointer are aligned.
Check valve clearance with cold engine.
Inlet valves (long rocker arm) = 0.2 mm.
Exhaust valves (short rocker arm) = 0.5 mm.
Adjust if deviation exceeds 0.1 mm.
Release locknut, set adjusting screw, tighten locknut to 90 +9 Nm.

Air filter — Removal and installation maintenance

Loosen clamp.
Remove air filter and clamp from flange of intake housing.
Verify no objects in flange of intake housing and clean it.
Place new air filter with clamp onto intake housing.
Tighten clamp.
Reset signal ring of service indicator.

Battery-charging generator drive — Drive belt replacement maintenance

⚠ Spring/circlip/tensioning roller preload. Risk of injury. Only use specified tool and equipment.

Tools: Socket adapter or box wrench

Remove guard cover.
Slacken screws (1) and (2) by half a turn.
Place socket adapter or box wrench on screw (3) and press belt tensioner fully.
Tighten screw (2).
Remove used drive belt.
Fit new drive belt.
Slacken screw (2) by half a turn.
Tighten screw (1) to 42 Nm and screw (2) to 60 Nm up to 65 Nm.
Install guard cover.
Readjust belt tension after 30 minutes and again after 8 hours engine runtime.

Centrifugal oil filter — Cleaning and filter-sleeve replacement maintenance

⚠ Hot oil. Wear protective clothing, gloves, goggles. Avoid contact with skin. Do not inhale oil vapor.

⚠ Compressed air: do not direct jet at persons; wear protective goggles/safety mask and ear protectors.

Tools: Torque wrench 6-50 Nm F30027336

Remove clamp.
Release Tommy nut and take off cover.
Carefully lift rotor, allow oil to drain and remove from housing.
Release rotor cover nut.
Take off rotor cover.
Remove filter sleeve.
Measure thickness of oil residues on filter sleeve.
Assemble with new filter sleeve and sealing rings; tighten rotor cover nut 35-45 Nm, clamp 8-10 Nm, cover nut 5-7 Nm.

Engine coolant — Draining maintenance

⚠ Coolant is hot and under pressure. Risk of injury and scalding. Let engine cool down. Wear protective clothing, gloves, goggles/safety mask.

Provide appropriate container.
Switch off preheating unit.
Turn breather valve of coolant expansion tank counterclockwise to first stop and allow pressure to escape.
Continue to turn and remove breather valve.
Draw off segregated corrosion inhibitor oil in expansion tank.
Open drain cocks or drain plugs and drain coolant at preheating unit, thermostat housing, U-bend, HT coolant pump elbow, crankcase left and right side.
Close all open drain points.
Place breather valve on filler neck and close.

Engine coolant — Filling maintenance

⚠ Coolant is hot and under pressure. Let engine cool down. Fill/top up coolant only into cold engine.

Turn breather valve of filler neck counterclockwise to first stop and allow pressure to escape.
Continue to turn and remove breather valve.
Connect appropriate pump with hose to drain valve of engine coolant pump.
Open vents at distributor and exhaust turbochargers.
Open drain valve and pump coolant into engine at 0.5 bar minimum.
When coolant emerges from vent points, close vent points successively from lowest to highest.
Fill expansion tank until overflow edge is reached.
Close drain valve, fit breather valve, start engine.
After engine has run unloaded for 10 seconds, stop engine.
Check coolant level and top up if required.

Engine oil — Change maintenance

⚠ Hot oil. Oil can contain combustion residues harmful to health. Wear protective clothing, gloves, goggles. Avoid contact with skin. Do not inhale oil vapor.

Tools: Torque wrench 40-200 Nm F30027337, Ratchet adapter F30027341

Provide suitable container.
Drain oil at drain plug(s) on oil pan or extract with semirotary hand pump.
Drain residual oil at equipment carrier.
Replace engine oil filter.
Install drain plug(s) with new sealing ring; tighten drain plugs (2),(3) to 100 Nm +10 Nm.
Fill with new oil up to max mark at oil dipstick.
Check engine oil level.
Bar engine with starting system.

Engine — Barring manually maintenance

⚠ Before barring the engine, ensure that nobody is in the danger zone.

Tools: Barring gear F6555766, Ratchet head with extension F30006212

Remove guard plate.
Engage barring tool with ring gear and mount on flywheel housing.
Set ratchet onto barring tool.
Rotate crankshaft in engine direction of rotation.
Check for abnormal resistance.
Remove barring tool in reverse sequence.

Engine — Barring with starting system maintenance

⚠ Before barring or starting the engine, ensure nobody is in danger zone.

⚠ After working on engine, check all protective devices reinstalled and all tools removed.

Release latch of connector X4.
Disconnect connector from engine governor.
Press START button.
Let crankshaft rotate until oil pressure is indicated.
Stop engine after approx. 20 seconds.
Connect connector X4 to engine governor and latch.

Fuel filter — Replacement maintenance

⚠ Fuels are combustible. Avoid open flames, electrical sparks and ignition sources. Do not smoke.

Tools: Filter wrench F30379104

Remove easy-change filter using filter wrench.
Clean sealing face of filter head.
Slightly lubricate seal on easy-change filter.
Screw on easy-change filter by hand until seal makes contact and tighten finger-tight.
Vent fuel system.

Fuel system — Venting maintenance

⚠ Fuels are combustible. Avoid open flames, electrical sparks and ignition sources. Do not smoke.

Open vent plug.
Unlock fuel priming pump, screw out handle by turning counterclockwise.
Operate pump with handle until bubble-free fuel emerges.
Close vent plug.
Screw in handle turning clockwise.
Verify fuel priming pump handle is tightened.

Injector — Removal and Installation repair

⚠ Fuels are combustible. Avoid open flames, electrical sparks and ignition sources. Do not smoke.

Tools: Installation/removal tool for injector F6789889, Milling cutter F30452739, Slotted nut driver F30452578, Torque wrench 0.5-5 Nm 0015384230, Torque wrench 10-60 Nm F30510423, Torque wrench 60-320 Nm F30047446

Shut off fuel supply to engine.
Remove cylinder head cover.
Withdraw cable connector on injector.
Remove HP fuel line and return line.
Remove adapter.
Remove screw and take off hold-down clamp.
Install removal tool and remove injector.
Remove sealing ring, O-rings and damping ring.

Extracted from the manufacturer documentation linked to this model. Values are copied as printed; confirm against your unit's manual and serial number.

Parts cataloged across the MTU 20V4000 family

Part #	Description	Category
07500159b	Adapter, Injector	adapter
2020161	Air filter	air_filter
W1003	Replace air filter (→Page 6 – 36)	air_filter
W1005	Air filters	air_filter
WM00076	Air filter element	air_filter
21300116a	Drive belt condition check	belt
21300167a	Battery-charging generator drive — Drive belt tension adjustment	belt
21300167b	Battery-charging generator drive — Drive belt replacement	belt
F6557991	Puller bracket	bracket
W1009	Centrifugal oil filter (if fitted)	centrifugal_oil_filter
30380	Cleaner (Hakupur 312)	cleaner
W1011	Combustion chambers	combustion_chambers
W2004	Fit new high-pressure sensor in fuel system.	component_maintenance
W2006	Check engine coolant thermostat and fit new thermal actuator.	component_maintenance
W2007	Check charge-air coolant thermostat and fit new thermal actuator.	component_maintenance
W2009	Inspect centrifugal oil filter for wear (if fitted).	component_maintenance
W2010	Overhaul starter.	component_maintenance
W2062	Fit new sealing materials for all components disassembled.	component_maintenance
07500160a1	Cable connector, Injector	connector
20300173a	Coolant filter	coolant_filter
W1055	Overhaul cylinder heads, visually inspect piston crowns and running pattern of cylinder liners (→Workshop Manual)	cylinder_head
W1063	Overhaul cylinder heads. Visually inspect piston crowns and wear pattern on cylinder liner running surfaces.	cylinder_heads
W1038	Overhaul exhaust turbocharger (→Workshop Manual)	exhaust_turbocharger
W3000	Completely disassemble the engine. Inspect engine components as per Maintenance Manual instructions and repair or fit new components as required.	extended_component_maintenance
07500211a	Screw, Adapter (3)	fastener
08300126a	Easy-change filter	filter
40477	Assembly paste (Optimoly Paste White T)	fluid
X00029933	Grease (Kluthe Hakuform 30-10/Emulgier)	fluid
W1051	Overhaul fuel delivery pump (→Workshop Manual)	fuel_delivery_pump
W1001	Fuel filter or new fuel filter insert	fuel_filter
WM00086	Easy-change fuel filter	fuel_filter
W1006	Fuel injectors	fuel_injectors
01200210a	Gasket	gasket
04000047a	Sealing ring, Injector	gasket
07500220a	O-rings (2) and damping ring (3), Injector	gasket
08300029b	Gasket	gasket
F30027340	Ratchet adapter	hand_tool
20200220a	Disconnect pump and hose.	hose
07600211a	Injector	injector
507015174	Injectors Y39.1 to Y39.8, engine side A (underneath the cylinder head covers of the cylinders)	injector
F30378403	Injector installation jig	jig
F6555197	Lever for force-in lever	lever
F6557952	Force-in lever for injector installation	lever
W1008	Engine oil filter	oil_filter
WM00067	Oil filter element	oil_filter
0.04	PM	other_service
0.37	CO	other_service
0135315483	Connector pliers	other_service
1020FDL1106	Generator Model	other_service
1020FDM1182	Generator Model	other_service
1020FDS1124	Generator Model	other_service
1030FDH1252	Generator Model	other_service
1030FDH1254	Generator Model	other_service
1030FDL1110	Generator Model	other_service
10311583	Colt Hayes	other_service
20300174a	Sealing ring	other_service
217.3	Heat Radiated to Ambient	other_service
28149	Dry Weight	other_service
5.95	NOx + NMHC	other_service
60.6	Fan Power	other_service
95.4	Displacement	other_service
97.5	Sound Level	other_service
A001061/	MTU Fluids and Lubricants Specification	other_service
F30047446	Torque wrench, 60-320 Nm	other_service
F30510423	Torque wrench, 10-60 Nm	other_service
F6555766	Barring tool	other_service
M015565/01E	Air Filter	other_service
M015565/02E	Cooling system (LT circuit)	other_service
M015715/00E		other_service
MTU-015715/00E	Special tools	other_service
MTU-06-08	Safety instructions	other_service
F30377769	Puller for injector removal	puller
20300176a	Charge-air coolant pump — Relief bore check	pump
50701513a	Temperature sensors for single exhaust gas B4.1 to B4.8 (engine side A)	sensor
507015144	Temperature sensors for single exhaust gas B4.11 to B4.18 (engine side B)	sensor
F30027336	Torque wrench 6-50 Nm	special_tools
F6789889	Installation/removal tool for injector	special_tools
W2005	Check engine coolant thermostat and replace thermal actuator (→Workshop Manual)	thermostat
0015384230	Torque wrench, 0.5-5 Nm	tool
F30452578	Slotted nut driver, 0.5-5 Nm	tool
F30452739	Milling cutter	tool
W1002	Check valve clearance (→Page 6 – 10)	valve_gear

Parts cataloged across all variants of this engine family — verify the exact part fits your specific variant and serial number before ordering.

Common questions

What is the oil capacity of the MTU 20V 4000 Gx3?

The MTU 20V 4000 Gx3 engine has an oil capacity of 390.0 liters.

What is the displacement of the MTU 20V 4000 Gx3?

The MTU 20V 4000 Gx3 has a displacement of 95.4 liters with 20 cylinders.

How often should you change the oil in the MTU 20V 4000 Gx3?

The MTU 20V 4000 Gx3 oil change interval is every 100 hours.

What is a common problem with the MTU 20V 4000 Gx3 engine?

A commonly reported issue on generators using the MTU 20V 4000 Gx3 is: SS Starter Speed Not Reached. Fix: Contact Service..