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Cummins/Onan KTA50-G8 Engine

The Cummins/Onan KTA50-G8 is a 50 L 16-cylinder turbo aftercooled engine rated at 1500 rpm. It powers generator sets from Cummins/Onan, including the 1025DFLE, 1125 DFLE, 1250DFLE and 1290DFLE. It holds 204 L (53.9 gal) of oil and 400 L (105.7 gal) of coolant.

Also known as: Cummins KTA50-G8, KTA50G8

Part of the Cummins/Onan KTA50 engine family — 19 variants share parts & fitment.

50.0 L

Displacement

Cylinders

1500 rpm

Rated speed

204.0 L

Oil capacity

On this pageSpecs Generator sets FAQ Service intervals Torque & specs Fluids Procedures Wiring

Engine specifications

Oil capacity	204.0 L
Coolant capacity	400.0 L
Displacement	50.0 L
Cylinders	16
Aspiration	Turbo Aftercooled
Rated speed	1500 rpm

Generator sets powered by this engine

Cummins/Onan 1025DFLECummins/Onan 1125 DFLECummins/Onan 1250DFLECummins/Onan 1290DFLECummins/Onan 1340 DFLECummins/Onan KTA50

How to read your Cummins/Onan engine serial & model number →

Common problems

Over Current 1471
Low Coolant Level 197
Weak Battery 1442
Under Frequency 1448
Too Long in Idle 2342
Speed/Hz Match 1469
Speed Signal Lost 121
Shutdown After Battle Short 1123
Short Circuit 1445
Remote Emergency Stop 1434
Pre-Low Oil Pressure Sensor 143
Pre-High Cool Temp 146
Power Down Failure 1417
Overspeed 234
Over Frequency 1449

Compiled from service & troubleshooting documentation across every generator set that uses the Cummins/Onan KTA50-G8.

Service intervals

Item	Action	Hours	Months	Notes
Вентиляционные устройства генератора	Check	10 hr		10 часов / еженедельно
Весь агрегат	Test	10 hr		Включение минимум на час, предпочтительно с нагрузкой 50 %; 10 часов / еженедельно
Подключение вспомогательной клеммной коробки	Check	10 hr		10 часов / еженедельно
Уровень охладителя воды	Check	10 hr		10 часов / еженедельно
Уровень смазочного масла в двигателе	Check	10 hr		10 часов / еженедельно
Уровень топлива	Check	10 hr		10 часов / еженедельно
Уровень электролита в батарее	Check	10 hr		10 часов / еженедельно
Вентиляционный клапан топливного бака	Check	100 hr		100 часов / ежемесячно (положение отметки в таблице)
Все переключатели (в т.ч. двигателя)	Test	100 hr		100 часов / ежемесячно
Осадок в топливном баке	Drain	100 hr		100 часов / ежемесячно (положение отметки в таблице)
Отверстие и внутреннее пространство генератора	Clean	100 hr		Очистка сухим воздухом; 100 часов / ежемесячно
Соленоид подачи топлива	Check	100 hr		100 часов / ежемесячно
Уровень зарядки батареи гидрометром	Test	100 hr		100 часов / ежемесячно
Воздушный фильтр (у масляного – уровень масла)	Check	200 hr		200 часов / ежегодно
Все болты и гайки	Check	200 hr		Проверка и затягивание при необходимости; 200 часов / ежегодно
Все реле распределительной аппаратуры	Test	200 hr		200 часов / ежегодно
Кабельные контакты батареи	Clean	200 hr		200 часов / ежегодно; зачистка и смазка
Линии топлива, воздуха и выхлопная система на протечки	Check	200 hr		200 часов / ежегодно
Натяжение клиновидного ремня	Check	200 hr		200 часов / ежегодно
Плавкие предохранители и отключающие устройства	Check	200 hr		200 часов / ежегодно
Подшипники генератора	Lubricate	200 hr		200 часов / ежегодно
Проверка агрегата изготовителем	Inspect	200 hr		200 часов / ежегодно
Противовибрационные устройства	Check	200 hr		При наличии таковых; 200 часов / ежегодно
Смазочное масло	Change	200 hr		200 часов / ежегодно
Чистка всего агрегата и наружной поверхности панели управления	Clean	200 hr		200 часов / ежегодно
Чистота контакторов и контактов прерывателей	Check	200 hr		200 часов / ежегодно
Air cleaner element - restriction	Check	250 hr	6 mo	Replace air cleaner element as required
All belts	Check	250 hr	6 mo
Cooling fan	Check	250 hr	6 mo	Check for cracks, loose rivets, bent or loose blades
Engine oil	Change	250 hr	6 mo	Whichever occurs first
Fan idler pivot arm	Lubricate	250 hr	6 mo	Water pump type grease until grease appears
Front engine support	Lubricate	250 hr	6 mo	Chevron SRI grease or equivalent
Fuel filter	Replace	250 hr	6 mo
Hoses	Inspect	250 hr	6 mo	Check/replace as required
Oil filters	Change	250 hr	6 mo	Change filters with oil
Pulley tensioner	Check	250 hr	6 mo
Engine oil filters	Change	805 hr		Last changed date and HRS: 2/3/2025, 805HRS
Batteries	Check	1500 hr	12 mo
Cold start aids	Check	1500 hr	12 mo	Seasonal
Crankshaft end clearance	Inspect	1500 hr	12 mo

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	Crankshaft end clearance	0.13 MIN / 0.51 MAX	mm
Clearance	Fan hub bearing end clearance	0.03 MIN / 0.15 MAX	mm
Clearance	Thermostat seal installation depth	no more than 0.51	mm	below top of cast edge
Clearance	Turbocharger BB (RR-151) and (RR-153) end clearance	0.09 MIN / 0.13 MAX	mm
Clearance	Turbocharger BB bearing radial clearance - RR-151	0.75 MAX	mm	0.030 in
Clearance	Turbocharger BB bearing radial clearance - RR-153	0.55 MAX	mm	0.021 in
Clearance	Turbocharger axial end play - HC5A	0.05 MIN / 0.13 MAX	mm
Clearance	Turbocharger axial end play - HT7100	0.06 MIN / 0.16 MAX	mm
Clearance	Turbocharger axial end play - T18A	0.10 MIN / 0.23 MAX	mm
Clearance	Turbocharger radial clearance compressor impeller - HC5A	0.15 MIN / 0.45 MAX	mm
Clearance	Turbocharger radial clearance turbine wheel - HC5A	0.20 MIN / 0.55 MAX	mm
Gap	Heat exchanger zinc plug erosion limit A	approximately 19	mm	0.75 in; new 51 mm [2 in]
Gap	Heat exchanger zinc plug erosion limit B	approximately 6.4	mm	0.25 in; new 16 mm [0.625 in]
Other	Air compressor discharge carbon deposit thickness limit	2	mm	1/16 in
Other	Alternator belt tension	356	N	80 lbf, Burroughs tension gauge GT-1293
Other	Maximum vibration damper thickness - Houdaille	66.38	mm	2.574 in
Other	Maximum vibration damper thickness - Made in England Before F-82	65.91	mm	2.595 in
Other	Maximum vibration damper thickness - Made in England F-82 and After	65.66	mm	2.585 in
Other	PTD injector travel verification specification	7.80 MIN / 7.82 MAX	mm
Other	PTD non-top stop injector travel adjustment	7.82	mm
Other	PTD non-top stop injector travel limits	7.77 to 7.87	mm
Other	Two pulley fan drive belt tension (set)	2668.9 to 2891.3	N	600 to 650 lbf
Other	Two pulley fan drive belt tension (verify)	2891.3 to 3336.2	N	650 to 750 lbf
Other	Vibration damper thickness variation (four readings 90 degrees apart)	must not vary more than 0.25	mm	0.010 in
Other	Глубина фундамента/цоколя и выступ за пределы агрегата	не менее 150	мм (6 дюймов)
Other	Минимальное расстояние от генератора до стены, резервуара или панели в машинном зале	1	м
Other	Нагрузка на грунт (ННГ) от агрегата, охладителя, топлива и фундамента	менее 9800	кг/м2 (2000 фунтов на кв. фут) или 96 кПа	требует проверки по местным нормам
Other	Площадь впускного отверстия воздуха для агрегатов с радиаторным охлаждением	в 1,5-2 раза больше площади радиатора
Other	Просвет выхлопной трубы глушителя	12	дюйма (300 мм)	двигатель QSK60
Other	Просвет выхлопной трубы глушителя	3	дюйма (76 мм)	двигатели B3.3, 4B, 6B
Other	Просвет выхлопной трубы глушителя	4	дюйма (100 мм)	двигатель 6C
Other	Просвет выхлопной трубы глушителя	6	дюйма (152 мм)	двигатели L, N, K19, V28
Other	Просвет выхлопной трубы глушителя	6×2	дюйма (152 мм)	двигатели K38, QSK30
Other	Просвет выхлопной трубы глушителя	8	дюйма (200 мм)	двигатели K50, QSK15
Other	Прочность бетона фундамента на сжатие (28 суток)	не менее 17200	кПа (2500 фунтов на кв. дюйм)
Pressure	Coolant pressure cap minimum	50	kPa	7 psi
Pressure	Exhaust back pressure maximum	75	mm Hg	3 in Hg, at rated speed and load
Pressure	Maximum allowable intake restriction - clean filter element	380	mm H2O	15 in H2O
Pressure	Maximum allowable intake restriction - dirty filter element	635	mm H2O	25 in H2O
Pressure	Maximum allowable restriction to fuel pump - clean filter	100	mm Hg	4 in Hg, at rated power
Pressure	Maximum allowable restriction to fuel pump - dirty filter	200	mm Hg	8 in Hg, at rated power
Pressure	Maximum allowable return line restriction	63	mm Hg	2.5 in Hg
Pressure	Maximum allowable return line restriction with check valves and/or overhead tanks	165	mm Hg	6.5 in Hg
Pressure	Oil Pressure	100		warm up
Pressure	Oil Pressure	80		15 Min. through 1 Hour at 1500 kW
Pressure	Oil Pressure	90		cool down
Pressure	Oil pressure, main oil rifle, maximum at rated RPM	483	kPa	15W-40 oil at 107 C [225 F]
Pressure	Oil pressure, main oil rifle, minimum at idle RPM	138	kPa	15W-40 oil at 107 C [225 F]
Pressure	Oil pressure, main oil rifle, minimum at rated RPM	310	kPa	15W-40 oil at 107 C [225 F]
Pressure	Throttle air cylinder leak test pressure	689	kPa	100 psi
Pressure	Throttle air cylinder test pressure	560	kPa	80 psi
Pressure	Предел обратного давления в выхлопной системе (большинство агрегатов Cummins)	3	дюйма рт. ст. (76 мм рт. ст.)	у последних моделей при максимальном потоке снижено до 2 дюймов рт. ст. (50 мм рт. ст.)
Resistance	Сопротивление электрода заземления при глухом занулении генераторной установки	не более 20	Ом	рекомендуется, независимо от системы защиты
Speed	Engine speed must not exceed	2400	RPM	under any circumstances
Speed	Hertz/Cycles	60	Hz	warm up through cool down
Temperature	Ambient Temperature	35	°F	warm up through 30 Min.
Temperature	Ambient Temperature	36	°F	45 Min. through cool down
Temperature	Coolant Temperature	165	°F	cool down
Temperature	Coolant Temperature	170	°F	15 Min. through 1 Hour at 1500 kW
Temperature	LTA modulating thermostat range	74 - 82	C	165 - 180 F

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	Ambient	Notes
Coolant	50/50 low-silicate antifreeze and quality water	ASTM D4985 (less than 0.10% silicate as Na2SiO5)		Must be pre-charged with supplemental coolant additives (DCA4) to 1.5 units per gallon; never below 1.2 or above 3 units per gallon. Do not use soluble oils.
Coolant	Смесь воды и антифриза 50/50; низкосиликатный антифриз	Добавка Cummins DCA4 или эквивалент		Вода чистая, без хлоридов, сульфатов и кислот, с pH от 8,5 до 10,5; при заполнении холодной системы остается 6 (максимум 8) % дополнительной емкости для расширения
Engine oil	SAE 15W-40	API CE or CF4 (CD or CD/SF where CE/CF4 not available)		Multigrade preferred; sulfated ash limit must not exceed 1.85 mass percent. Arctic operation (below -23 C) use synthetic CE/SF 5W-30.
Fuel	ASTM No. 2 diesel			Below 0 C use blends of No. 2D and No. 1D. Viscosity must be kept above 1.3 cSt. Do NOT mix gasoline or alcohol with diesel fuel.
Fuel	Дизельное топливо класса А1 или А2	BS 2869: Часть 1:1998 (класс А1); BS 2869: Часть 2:1998 (классы А2, С1, С2, D, E, F, G, H)		Топливо должно быть как можно более чистым, по возможности не содержать воды и загрязнений
Grease	Water pump type grease (Amoco Rykon Premium No. 2 / Chevron SRI / Exxon Unirex N2 / Shell Dolium R / Texaco Premium RB)			Fan idler pivot arm and front engine support lubrication
Other	Природный газ	Наименьшая теплопроизводительность >30 МДж/Н·м3; плотность 0,7-0,9 кг/м3; метановое число >52; H2S >0,01 %; максимальная температура газа 50 °C	below 50°C	Требования к качеству газа для газовых двигателей; при несоответствии двигатель должен быть отключен

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

Procedures

Alternator Belt Adjustment adjustment

⚠ Over-tensioning of alternator belts can result in premature accessory drive bushing wear and seal leakage.

Tools: GT-1293 Burroughs Tension Gauge

Loosen the alternator and adjusting link mounting capscrews.
Loosen the jam nuts on the adjusting screw.
Turn the adjusting screw clockwise to tighten the belt tension.
Check the belt tension with a gauge.
Tighten the jam nuts on the adjusting screw to 55 Nm [40 ft-lb].
Tighten the adjusting link and alternator mounting capscrews to 55 Nm [40 ft-lb].
Check the belt tension again.

Crossheads - Adjustment adjustment

Tools: ST-669 Torque Wrench Adapter

Adjust the crossheads on the cylinder that has both valves closed.
Loosen the crosshead adjusting screw locknuts on the intake and exhaust valve crossheads.
Turn the adjusting screw out at least one turn.
Hold the crosshead down against its guide.
Turn the adjusting screw in until it touches the top of the valve stem but does not raise the crosshead.
Hold the adjusting screw and tighten the lock nut to the torque value.

Dipstick Calibration adjustment

⚠ The dipstick will break if the scribe mark is too deep.

Tools: scribe

Drain the oil from the pan.
Install the dipstick in the dipstick tube.
Use clean 15W-40 oil to fill the oil pan to the specified low level.
Remove the dipstick and scribe a mark across the dipstick at the oil level. Mark the low level with an L.
Install the dipstick and add additional oil to the specified full level.
Remove the dipstick and scribe a mark across the dipstick at the oil level. Mark the high oil level with an H.

PT (type D) Injector - Adjustment adjustment

⚠ The injector plunger is under spring tension. Do NOT allow the tool to slip.

⚠ Prevent damage to the indicator by allowing the lever to return slowly.

Tools: 3822575 injector and valve adjustment kit, 3822574 rocker lever actuator, ST-669 Torque Wrench Adapter

Assemble the parts of an injector and valve adjustment kit, Part No. 3822575, or equivalent, and install it on the cylinder.
Adjust the indicator so the tip touches the top of the injector plunger.
Lower the indicator 12.25 mm [0.5 inch] to allow for travel. Lock the indicator support to the post.
Use a rocker lever actuator, Part No. 3822574, or equivalent. Depress the lever until the injector bottoms two or three times.
Hold the lever with the injector plunger firmly bottomed and set the indicator to ZERO.
Turn the adjusting screw until the indicator reads the specified travel.
Tighten the locknut to the torque value.
Check the injector adjustment and repeat if not within specification.

Valves - Adjustment adjustment

⚠ Use the correct chart for the engine being serviced or the parts will be damaged.

Tools: 3376592 Inch Pound Torque Wrench, ST-669 Torque Wrench Adapter, feeler gauge

Select a feeler gauge for the correct valve lash specification and insert the gauge between the rocker lever and the crosshead.
Torque wrench method: use Part No. 3376592 inch pound torque wrench and tighten the adjusting screw to 0.68 Nm [6 in-lb].
Feel method: use a screwdriver and turn the adjusting screw only until the lever touches the feeler gauge.
The adjusting screw must not turn when the locknut is tightened.
Tighten the locknut to the value indicated.
The feeler gauge must slide backward and forward with only a slight drag.
Attempt to insert a feeler gauge 0.03 mm [0.001 in] thicker; the lash is not correct when the thicker gauge will fit.
Repeat until clearance is correct on both intake and exhaust valves.

Установка и подключение аккумуляторной системы installation

⚠ При зарядке батарей выделяются взрывоопасные газы – обеспечьте вентиляцию, вдали от искр и открытого огня.

⚠ Перед подключением батарей переключатель Run/Off/Auto на панели управления должен находиться в положении Off (ВЫКЛ).

⚠ Не устанавливайте кислотные батареи в одном помещении с никель-кадмиевыми.

Tools: Торцевой гаечный ключ

Установите батареи в чистое, хорошо освещенное и вентилируемое место с легким доступом для обслуживания.
Подключайте землю ПОСЛЕДНЕЙ, а при извлечении батареи отключайте ее ПЕРВОЙ.
Вначале подключайте ПЛЮСОВОЙ кабель генератора, затем минусовой; соблюдайте полярность.
Тщательно затяните гайки межъячеечных соединений и смажьте контакты вазелиновым маслом.
Для 24 В соедините две или четыре 12-вольтовые батареи последовательно.

Air Cleaner Element Replacement - Single Heavy Duty Dry-Type maintenance

⚠ Holes, loose end seals, dented sealing surfaces and other damage require immediate element replacement.

⚠ Pull the cover and element straight out to avoid damage.

Wipe dirt from the cover and upper portion of the air cleaner before disassembly.
Loosen the wing bolt and band clamp securing the dust pan.
Loosen the wing nut and remove the dust shield from the dust pan. Clean the dust pan and shield.
Remove the wing nut securing the primary element and inspect the rubber sealing washer.
Remove the dirty cleaner element and install the new primary element.
Make sure the rubber sealing washer is in place under the wing nut before tightening.
Assemble the dust shield and dust pan and secure with the band clamp.

Coolant Filter Replacement maintenance

⚠ Do NOT remove the radiator cap from a hot engine.

⚠ Do not allow oil to get in the filter; it will adversely affect the DCA.

Remove the coolant system pressure cap and close the shutoff valve(s), if equipped, before removing the coolant filter.
Push in the knob on the filter head or close the gate valve.
Lubricate the seal on the new filter with engine oil.
Install the new coolant filter. Turn the filter until the seal touches the filter head.
Turn the filter an additional 1/2 to 3/4 of a turn after contact.
Pull the knob on the filter head out or open the gate valve.

Cooling System Cleaning and Changing Antifreeze maintenance

⚠ Do not use caustic cleaners in the cooling system. Aluminum components will be damaged.

⚠ Wait until the temperature is below 50 C [120 F] before removing the coolant system pressure cap.

Drain the cooling system. Do not allow the cooling system to dry out. Do not remove the coolant filter.
Add 3.8 liters [1 U.S. gallon] of Fleetguard RESTORE (or equivalent) for each 38 to 57 liters [10 to 15 gallons] of cooling system capacity and fill with plain water.
Turn the heater temperature switch to high to allow maximum coolant flow.
Operate the engine at normal operating temperatures (at least 85 C [185 F]) for 1 to 1 1/2 hours.
Shut the engine off and drain the cooling system.
Fill with clean water to flush and operate at high idle for 5 minutes above 85 C [185 F].
Shut the engine off and drain. Repeat flushing if the water is still dirty.
Refill the system with new heavy duty coolant and SCA.

Fan Hub Inspection maintenance

Tools: dial indicator

Remove the fan belt.
Rotate the fan hub pulley to check for rough or damaged bearings.
Inspect the pulley grooves for excessive wear.
Check for grease leakage.
Use a dial indicator to check the bearing end clearance.
Replace with a new or rebuilt unit as necessary.
Install the fan belt.

Fuel Filter(s) Replacement maintenance

Tools: 3375049 filter wrench

Clean the area around the fuel filter head and replace the fuel filter(s).
Use a filter wrench, Part No. 3375049, to remove the fuel filter.
Clean the filter head gasket surface with a clean, lint-free towel.
Apply a light film of clean engine oil to the filter gasket surface.
Fill the filter with clean fuel.
Install the filter on the filter head and tighten until the gasket contacts the filter head surface.
Tighten the filter per the filter manufacturer's instructions.

Lubricating Oil and Oil Filter Changing/Replacement maintenance

⚠ Avoid direct contact of hot oil with your skin.

⚠ Fill the oil filters with clean lubricating oil before installation.

Tools: 3375049 oil filter wrench

Operate the engine until water temperature reaches 60 C [140 F]. Shut off the engine.
Remove the oil drain plug and drain the oil immediately.
Clean the area around the lubricating oil filter head and the gasket surface.
Use an oil filter wrench, Part No. 3375049, or equivalent, to remove the oil filters.
Apply a light film of lubricating oil to the gasket sealing surface before installing the new filters.
Fill the oil filters with clean lubricating oil.
Install the filters as specified by the filter manufacturer.
Check and clean the oil drain plug threads and seal surface.
Install and tighten the oil drain plug to 100 Nm [75 ft-lb].
Fill the engine with clean oil to the correct level.
Operate the engine at idle to inspect for leaks; shut off and check oil level again; add oil to the high H mark.

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

Voltage reconnection

Voltage	Phase	Connection	Leads	Notes
277/480	3		12	Generator end is 12 lead reconnectable and has PMG permanent magnet generator

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 Cummins/Onan KTA50 family

300

Part #	Description	Category
140-2096	Element, Primary (Outer)	Air filter
140-2098	Air Cleaner - Throwaway Type	Air filter
140-2467	Element, Safety (Inner)	Air filter
140-2501	Cleaner, Air (Disposable)	Air filter
140-2502	Band, Mounting – Air Cleaner	Air filter
140-2503	Bracket, Mounting	Air filter
140-3163	Cleaner, Air (No Replaceable Element)	Air filter
140-3230	Cleaner, Air (Includes Elements - See Ref. No. 25 and 26)	Air filter
309-0272	Regulator, Voltage - 24 VDC (Used on 35 A MP Alternator)	Alternator
309-0561	Alternator & Drive Components Group Pulley. Alternator - Multi Groove (Use with 35 A MP Alternator)	Alternator
503-1743-01	Alternator & Orive Components Group Pulley, Alternator - Multi Groove (Use with 35 AMP Alternator)	Alternator
206587	CAP, MAIN BEARING	Bearing cap
206588	CAP, MAIN BEARING	Bearing cap
98-5347	Decal - Caution Fan Drive & Lube Components Group Belt.	Belt
106069	SCREW, HEXAGON HEAD CAP	Bolt
205584	SCREW, TWELVE POINT CAP	Bolt
206028	SCREW, SOCKET HEAD CAP	Bolt
3032633	SCREW, TWELVE POINT CAP	Bolt
3177945	SCREW, HEX FLANGE HEAD CAP	Bolt
3628452	SCREW, HEXAGON HEAD CAP	Bolt
S-112	SCREW, HEXAGON HEAD CAP	Bolt
205684	BRACKET, LIFTING	Bracket lifting
205230	BUSSING	Bushing
0300-4623-29	DFLB (600V)	Current transformer
0300-4623-30	DFLC (600V)	Current transformer
0300-4623-52	DFLB BR (0-480V)	Current transformer
0300-4623-54	DFLC BR (0-480V)	Current transformer
3178803	CYLINDER BLOCK OPTION BP6089	Cylinder block
3178910	CYLINDER BLOCK	Cylinder block
148582	DOE, PIN	Dowel pin
70662	DOE, PIN	Dowel pin
3629497	DRAINCOCK	Draincock
206224	PLUG, EXPANSION	Expansion plug
206742	PLUG, EXPANSION	Expansion plug
3629168	PLUG, EXPANSION	Expansion plug
122-0757	Filter. Water - W/Corosion Inhibiting Chemical	Filter
159-1445	Reservoir, Fuel	Fluid
FS1216	Fuel/Water Sep Spin-On	Fuel filter
121-0113	Gasket, Pump	Gasket
121-0117	Gasket, Hand Hole	Gasket
205059	WASHER, PLAIN	Gasket
3002993	DOE, RING	Gasket
3025485	WASHER, PLAIN	Gasket
3176857	DOE, RING	Gasket
3178450	WASHER, PLAIN	Gasket
3178457	WASHER, PLAIN	Gasket
M-4352581	Upper Gasket Set	Gasket
S-604	WASHER, LOCK	Gasket
S-610	WASHER, LOCK	Gasket
338-2529	Harness. Wiring	Harness
128-0108	Insulation, Hose – Bulk (Order By The Foot – 12 Feet Required)	Hose
130-3538	Chemical DCA4 Service Pre-Charging Complete System	Hose
130-3576	Clamp, Hose	Hose
130-5588-02	Tube, Water Heater	Hose
130-5589-02	Tube, Water Heater	Hose
130-5590-02	Tube, Water Heater	Hose
130-5591-02	Tube, Water Heater	Hose
338-2925	Hose, Radiator	Hose
501-0704	Line, Flexible Fuel - Fuel Out	Hose
501-0707	Line, Flexible Fuel - Fuel In	Hose
502-1162	Connector, Hose (3/8")	Hose
503-0183	Clamp, Hose	Hose
503-0685	Clamp, Hose	Hose
503-0868	Clamp, Hose - T-Bolt Type (3.5" NON)	Hose
503-1140	Hose, Rubber	Hose
503-1484	Elbow, Hose (45 Deg) (7" ID)	Hose
503-1620	Hose – Bulk (3/8" ID) (Order by the Foot)	Hose
503-1727	Hose, Radiator (3” ID x 10”)	Hose
503-1728	Hose (3” ID x 5–1/2”)	Hose
503-1870-11	Clamp, Hose	Hose
503-1870-12	Clamp, Hose	Hose
505-0324	Hose. Bulk (Sold by the Foot) Two Feet Required Nipple, Pipe - Half (3/4 NPT x 2"LG)	Hose
518-0548-24	Clamp, Hose	Hose
98-5759	Drive - Multi Groove Hose, Flexible - Lube (Grease)	Hose
98-5842	Clamp, Hose - T-Bolt Type (3.5" NON)	Hose
3375004	Dial Indicator Kit for injector and valve adjustment	Injector
3822575	Injector and valve adjustment kit	Injector
FP-3053124	Injector Assembly, PTK (New)	Injector
3011884	INSERT, LINER	Insert liner
3019150	INSERT, LINER	Insert liner
3021148	INSERT, LINER	Insert liner
206580	BEARING, MAIN	Main bearing
206581	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Upper	Main bearing
206582	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Upper	Main bearing
206583	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Upper	Main bearing
206584	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Upper	Main bearing
206590	BEARING, MAIN	Main bearing
206591	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Lower	Main bearing
206592	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Lower	Main bearing
206593	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Lower	Main bearing
206594	BEARING, MAIN A/R No.2,3,4,5,6,7,&8, Lower	Main bearing
206600	BEARING, MAIN	Main bearing
206601	BEARING, MAIN A/R No.1&9, Upper	Main bearing
206602	BEARING, MAIN A/R No.1&9, Upper	Main bearing
206603	BEARING, MAIN A/R No.1&9, Upper	Main bearing
206604	BEARING, MAIN A/R No.1&9, Upper	Main bearing
206610	BEARING, MAIN	Main bearing
206611	BEARING, MAIN A/R No.1&9, Lower	Main bearing
206612	BEARING, MAIN A/R No.1&9, Lower	Main bearing
206613	BEARING, MAIN A/R No.1&9, Lower	Main bearing
206614	BEARING, MAIN A/R No.1&9, Lower	Main bearing
3018210	SET, MAIN BEARING STANDARD	Main bearing set
3018211	SET, MAIN BEARING A/R .010 Inch O/S	Main bearing set
3018212	SET, MAIN BEARING A/R .020 Inch O/S	Main bearing set
3018213	SET, MAIN BEARING A/R .030 Inch O/S	Main bearing set
LF3325	Full-flow spin-on lubricating oil filter element	Oil filter
016-40820	Harness, Wiring (Includes Cable Ties and Terminals)	Service part / kit
102-1335	Plug, Oil Drain	Service part / kit
121-0116	Cover, Hydraulic Hole	Service part / kit
130-2981	Cap. Radiator - 7#PSI	Service part / kit
130-3758	Radiator (includes Cap)	Service part / kit
140-1260	Fitting, Safety Filter	Service part / kit
140-1548	Indicator, Service	Service part / kit
140-2097	Cleaner, Air (Includes Elements)	Service part / kit
140-2099	Band	Service part / kit
140-2395	Tube, Air Inlet	Service part / kit
140-2504-01	Bracket - Right Side	Service part / kit
140-2504-02	Bracket - Left Side	Service part / kit
140-2508	Tube, Air Inlet (7" x 9" - 3/4")	Service part / kit
140-2509	Tube, Air Inlet	Service part / kit
140-2515	Bracket, Mounting	Service part / kit
140-2519	Tube, Air Inlet	Service part / kit
140-2521	Tube, Air Inlet	Service part / kit
140-2528	Shield – Air In Heat	Service part / kit
300-2856	Board Assy, Printed Circuit	Service part / kit
300-2863	Board Assy, Printed Circuit - Relay Assembly- (A14)	Service part / kit
3007525	(3022157) KIT, LINER LINER, CYLINDER	Service part / kit
301-9054-01	Decal - Panel Front Markings (Control With Meters)	Service part / kit
301-9054-02	Clip - Fastener	Service part / kit
301-9054-03	Clip - Fastener	Service part / kit
3012611	CYLINDER LINER (O/S) KIT, LINER A/R .020 inch O/S	Service part / kit
3012612	CYLINDER LINER (O/S) KIT, LINER A/R .030 Inch O/S	Service part / kit
302-1720	Meter, Frequency (M23)	Service part / kit
302-1753	Ammeter (M22) See Current Transformer & Ammeter Installation Figure for Parts)	Service part / kit
302-1800	Ammeter (M22) Scale in Amps as Indicated 0-2000/0-4000 (600 VAC Application) 0-3000/0-6000 (120-480 VAC Application)	Service part / kit
302-1908	Screw. Cap - Hex Head (M8-1.25 x 35MM)	Service part / kit
305-0813-01	Battery charger, Onan, 120V, 375W	Service part / kit
305-0818-02	EOOO-21002	Service part / kit
307-1056	Relay. 24 VDC	Service part / kit
307-1987	2 307-1056 3 3 815-0388 6 4 323-0804 3 5 815-0544 3 6 319-0447 1 7 NOTE 1 REF 8 NOTE 2	Service part / kit
308-0882	Decal - Panel Front Markings (Control Without Meters)	Service part / kit
309-0436	Decal - Model Identification ONAN GEN SET CUMMINS GEN SET CUMMINS ONAN GEN SET	Service part / kit
309-0437	(222"F)	Service part / kit
309-0635-02	Valve, Check	Service part / kit
3096680	Piston STC 13.8:1 Ratio	Service part / kit
3096681	Piston KT Series 15.5:1 Ratio	Service part / kit
3096682	Piston KTA Series 14.5:1 Ratio	Service part / kit
3096683	Piston 13.5:1 Ratio	Service part / kit
3096684	Piston KTA 15.7:1 Ratio	Service part / kit
3096685	Piston STC 13.9:1 Ratio	Service part / kit
319-0447	Screw. Machine - Pan Head. Cross-Recessed Drive (#6-32 x 1/2")	Service part / kit
319-0754	Tie. Cable	Service part / kit
322-0363	Component 322-0363	Service part / kit
323-0804	Screw. Machine - Round Head with IT Lock Washer (#6-32 x 1/2")	Service part / kit
323-1200	# Socket, Contact (Used in J1, J2)	Service part / kit
323-1304	tiotming, Umector	Service part / kit
323-1306	Genset component (SJB series)	Service part / kit
3318201	Battery Cable Group	Service part / kit
332-0052	Clamp, Loop	Service part / kit
332-0607	Block, Terminal (T81)	Service part / kit
332-1279	Terminal. Lug - Ring (3/8	Service part / kit
332-1292	Sender, Pressure - Oil (E123)	Service part / kit
332-1445	Tie, Cable 18 98-5219 1 Decal - Panel Front (Not I l l u s t r a t e d ) 19 98-5220 1 Decal	Service part / kit
332-1673	Terminal, Wire - Spade	Service part / kit
332-2634	Clamp, Hose	Service part / kit
332-2723	Strip. Marker	Service part / kit
333-0677-01	Heater, Coolant - 4990 Watt	Service part / kit
333-0677-02	Heater, Coolant - 6420 Watt	Service part / kit
3375005	Dial indicator extension	Service part / kit
3375007	Support Plate / Support Block for dial indicator	Service part / kit
338-1835	Harness, Wiring (A13 to A l l )	Service part / kit
338-1836	Harness, Wiring (A14 to All) (Relays)	Service part / kit
338-1904	Harness. Wiring (A15 to All)	Service part / kit
338-2278	Harness. Wiring - AC (Includes Terminal Block & Cable Ties) [Used only with meters]	Service part / kit
338-2532	Terminal. Lug - Forked (No. 6 Screw)	Service part / kit
355-0093	Voltmeter (M21) Dual Scale 0-300/0-600V Single Scale 0-750V	Service part / kit
3628731	Piston STC Kit	Service part / kit
3630913	Piston KTA-50-G7	Service part / kit
3631241	Piston Kit STC 13.9:1 Ratio	Service part / kit
3631242	Piston Kit 13.5:1 Ratio	Service part / kit
3631243	Piston Kit KTA 15.7:1 Ratio	Service part / kit
3631244	Piston Kit KTA Series 14.5:1 Ratio	Service part / kit
3631245	Piston Kit KT Series 15.5:1 Ratio	Service part / kit
3631246	Piston Kit STC 13.8:1 Ratio	Service part / kit
3801268	CYLINDER LINER (O/S) KIT, LINER A/R .040 Inch O/S	Service part / kit
3803530	Piston Assembly STC	Service part / kit
3804747	Piston Kit KTA-50-G7	Service part / kit
3804885	Piston KTA-50-G8/G9	Service part / kit
406-0333	Component 406-0333	Service part / kit
406-0334	Clip, Retaining - Turnbutton Fastener	Service part / kit
4089847	Piston Kit GTA38/19	Service part / kit
4090013	Piston Kit KTA-38-M2	Service part / kit
4090029	Piston Kit QSK19CE	Service part / kit
4090181	Piston GTA38/19	Service part / kit
4097889	Piston KTA-38-M2	Service part / kit
4910463	Piston QSK19R/M	Service part / kit
4910465	Piston QSK Series	Service part / kit
4916177	Piston GTA/GQSK19	Service part / kit
4918058	Piston QSK19CE	Service part / kit
4922319	Piston QSK19C	Service part / kit
4955233	Piston Kit QSK19R/M	Service part / kit
4955235	Piston Kit QSK Series	Service part / kit
4955236	Piston Kit QSK19C	Service part / kit
4955238	Piston Kit GTA/GQSK19	Service part / kit
501-0520	Screw, Cap - Hex Head (3/8-24 x 5/8")	Service part / kit
501-0524	Washer, Lock - EIT (3/8")	Service part / kit
501-0558	Line. Flexible - Bypass	Service part / kit
503-1717	Elbow, Reducer (45 Deg) (7" ID to 6" ID)	Service part / kit
503-1720	Insert, Reducer (6" OD to 5-1/2" ID)	Service part / kit
503-1730	503-0183 21 503-1731 22 505-0324 23 504-0171 24 505-0102 25 505-0132 26 505-0102 27 28 29	Service part / kit
504-0028	Valve, Radiator Drain	Service part / kit
505-0007	Belt. Drive - Multi Groove (Used with 35 A MP Alternator * Pulley, Alternator - Multi Groove (Use with 75 A MP Alternator)	Service part / kit
505-0017	Bushing, Pipe – Reducer (3/8" to 1/4")	Service part / kit
505-0021	Bushing, Pipe - Reducer (3/4º to 1/2º)	Service part / kit
505-0100	Nipple, Pipe - Close (1/2”)	Service part / kit
505-0102	Filter. Water - W/Corosion Inhibiting	Service part / kit
505-0117	Bushing, Reducer - Flush, Brass (1/2' NPT x3/8° NPT)	Service part / kit
505-0132	Nipple, Pipe - Close (3/4 NPT x l-3/8"LG) Elbow. Pipe - 90* (3/4 NPT)	Service part / kit
505-0376	Elbow – 45 Deg (3/8")	Service part / kit
508-0015	Washer, Insulating - Fiber (#8)	Service part / kit
511-0161-02	.*	Service part / kit
517-0131	Capacitor (Used across Voltmeter Terminals on some Sets)	Service part / kit
518-0548-42	Clamp, Retainer 4 Prior To December 1996 Production (Mounted On Top And Side Of Control Box Wrapper)	Service part / kit
526-0030	Washer, Flat (3/8")	Service part / kit
800-0055	Screw, Cap – Hex Head (3/8–16 x 2-1/4")	Service part / kit
800-0062	Nut, Insulated	Service part / kit
800-0094	Screw, Cap – Hex Head (1/2–13 x 2")	Service part / kit
800-0270	DCA4 Service Pre-Charging Complete System	Service part / kit
800-2060	Screw, Cap - Hex Head (M8x 1.25 x35)	Service part / kit
809-0035	Screw, Machine - Thread Cutting, Round Head (#8 X 3/4')	Service part / kit
812-0063	853-0003 300-2856 338-1836 812-0063 853-0003 300-2863 338-1835 332-1445 NOTE 1 NOTE 2 332	Service part / kit
812-0065	Screw, Machine - Round Head (#6 - 32 x 5/8')	Service part / kit
812-0084	Screw. Machine - Round Head (	Service part / kit
815-0388	Bracket. Mounting - Relay Lead(s), Electrical Wire, Electrical - 20 AW G, Insulated Terminal, Wire - Forked, 18-20 Gauge	Service part / kit
815-0544	Screw, Machine - Round Head IT Washer (#6 - 32 x 1/2')	Service part / kit
821-0004	Screw, Self-Locking - Hex	Service part / kit
821-0029	Screw, Self–Locking – Hex Washer Head (3/8–16 x 3/4")	Service part / kit
821-0033	Screw, Self–Locking – Hex Washer Head (7/16–14 x 3/4")	Service part / kit
821-5004-03	Screw, Self-Locking – Hex Washer Head (3/8–16 x 1")	Service part / kit
850-0050	Washer, Lock - Spring (3/8”)	Service part / kit
853-0003	Washer, Lock - ET (#6)	Service part / kit
856-0008	Washer, Lock - EIT (5/16'1)	Service part / kit
856-0010	Washer, Lock - EIT (3/8')	Service part / kit
870-0131	Nut. Hex - with ET (#10-32)	Service part / kit
870-0196	Nut, Insulating (#8)	Service part / kit
870-0281	Nut, Self-Locking – Hex Washer Head (3/8–16)	Service part / kit
900-0181	PCC Control Service Manual	Service part / kit
903-0128	NA	Service part / kit
903-0208	NA	Service part / kit
903-0608	NA	Service part / kit
98-4732	Caution	Service part / kit
98-4798	Decal - Caution "7# PSI HOT WATER SYSTEM"	Service part / kit
98-5298	Decal - Panel Rear Markings (All Control Panels)	Service part / kit
98-5299	Decal - Panel Rear Markings (All Control Panels)	Service part / kit
98-5316	Decal - Panel Rear Markings (All Control Panels)	Service part / kit
98-5387	Nut, Self-Locking - with ET Lockwasher (#10-32)	Service part / kit
98-5393	Screw, Tapping - Round Head (#8 x 3/4")	Service part / kit
98-5822	Bushing, Reducer - Flush (1/2 NPT x 3/8 NPT)	Service part / kit
98-6108-03	Decal - Model Identification	Service part / kit
98-6111-03	ONAN GEN SET CUMMINS GEN SET	Service part / kit
98-6139-03	CUMMINS ONAN GEN SET	Service part / kit
98-6169	Terminal Assembly (Includes Replaceable Items 26 thru 29)	Service part / kit
F-2375	A single line drawing of the prime power system	Service part / kit
M-3804747	Piston Kit	Service part / kit
68445	PIN, GROOVE	Pin
3628605	PLUG, PIPE	Pipe plug
3628607	PLUG, PIPE	Pipe plug
3178464	PLATE, COVER	Plate cover
121-0111	Drive, Pump	Pump
159-1451	Pump, Fuel Transfer	Pump
3011076	SEAL, D RING	Seal
3014668	SEAL, D RING	Seal
3081489	SEAL, OIL	Seal
3177556	SEAL, RECTANGULAR RING	Seal
508-0292	Washer, Sealing - Copper	Seal
509-0283-01	Seal	Seal
509-0336	Seal, O-Ring	Seal
509-0337	Seal, O-Ring	Seal
193-0244	Sender, Oil Pressure (E1)	Sensor
193-0375	Sender, Coolant	Sensor
309-0269	Sender, Temperature-Lo Engine	Sensor
960-0181	Service manual	Service manual
960-0302	Service manual	Service manual
960-0504	PCC Control Service Manual	Service manual
960-0507	Detector Control Service Manual	Service manual
3033853	SHAFT, IDLER	Shaft idler
3175281	SHAFT, IDLER	Shaft idler
205741	SHIM, A/R .007 Inch O/S	Shim
205742	SHIM, A/R .008 Inch O/S	Shim
205743	SHIM, A/R .009 Inch O/S	Shim
205744	SHIM, A/R .020 Inch O/S	Shim
205745	SHIM, A/R .031 Inch O/S	Shim
149-2232	Starter - 24 VDC	Starter
3000138	SUPPORT, BEARING	Support bearing
309-0649	Thermostat (Includes Connector Socket) (S11)	Thermostat
3000139	BEARING, THRUST	Thrust bearing
3001708	BEARING, THRUST A/R .010 Inch O/S	Thrust bearing
3001709	BEARING, THRUST A/R .020 Inch O/S	Thrust bearing
3001710	BEARING, THRUST A/R .030 Inch O/S	Thrust bearing
3001711	BEARING, THRUST A/R .040 Inch O/S	Thrust bearing

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 Cummins/Onan KTA50-G8?

The Cummins/Onan KTA50-G8 engine has an oil capacity of 204.0 liters.

What is the displacement of the Cummins/Onan KTA50-G8?

The Cummins/Onan KTA50-G8 has a displacement of 50.0 liters with 16 cylinders.

Which generators use the Cummins/Onan KTA50-G8 engine?

The Cummins/Onan KTA50-G8 powers 6 generator set(s), including Cummins/Onan 1025DFLE, Cummins/Onan 1125 DFLE, Cummins/Onan 1250DFLE, Cummins/Onan 1290DFLE, Cummins/Onan 1340 DFLE.

What is a common problem with the Cummins/Onan KTA50-G8 engine?

A commonly reported issue on generators using the Cummins/Onan KTA50-G8 is: Over Current.