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Generac GT-999 Engine

Name: Generac GT-999 Engine
Brand: Generac

The Generac GT-999 is a 1 L 2-cylinder naturally aspirated engine rated at 3600 rpm. It powers generator sets from Generac, including the 15 kW EcoGen, 8.1 GN and G0070420. It holds 1.8 L (0.5 gal) of oil.

Also known as: GT-999, Generac GT-999

0.999 L

Displacement

Cylinders

3600 rpm

Rated speed

1.8 L

Oil capacity

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

Engine specifications

Oil capacity	1.8 L
Displacement	0.999 L
Cylinders	2
Aspiration	Naturally aspirated
Rated speed	3600 rpm

Generator sets powered by this engine

Generac 15 kW EcoGen Generac 8.1 GN Generac G0070420

How to read your Generac engine serial & model number →

Common problems

DANGER 000001
Pièces mobiles. 000115
Asphyxie. 000103
Yellow LED illuminated in any state. YELLOW
Fix: Check the screen for additional information. Perform SERVICE A maintenance. Press ENTER to clear.
Engine will not crank.
Cause: 1. Blown fuse. 2. Loose, corroded, or defective battery cables. 3. Defective starter contact. 4. Defective starter motor. 5. Discharged battery.
Fix: 1. Correct short circuit condition by replacing 7.5 amp fuse in generator control panel. Contact an Independent Authorized Service Dealer (IASD) if fuse continues to blow. 2. Tighten, clean, or replace as necessary.* 3. *See #2. 4. *See #2. 5. Charge or replace battery.
Unit consumes large amounts of oil
Cause: Excessive engine oil.
Fix: Adjust oil to correct level. See checking engine oil level section in owner’s manual.
Engine will not crank
Cause: Blown fuse.
Fix: Correct short circuit condition by replacing 7.5A fuse in generator control panel. Contact an IASD if fuse continues to blow.
Engine starts hard and runs rough
Cause: Plugged or damaged air cleaner.
Fix: Inspect and clean or replace air cleaner.
Engine cranks but will not start
Cause: No fuel.
Fix: Replenish fuel / turn on fuel shutoff valve.
Surfaces chaudes. 000108
Seul un électricien formé et agréé devrait s’occuper du câblage et des connexions à l’appareil. 000155
Seul un technicien qualifié peut installer, utiliser et entretenir cet équipement. 000182
Risque environnemental. 000228
Retour d’énergie électrique. 000237
MISE EN GARDE 000003

Compiled from service & troubleshooting documentation across every generator set that uses the Generac GT-999.

Maintenance schedule

Item	Spec	Capacity	Part #	Interval
Air filter			0J8478	1000 hr	Amazon $28.99 eBay $20.00 KuduParts $15.00
Oil filter	American Petroleum Institute (API) Service Class SJ, SL or better		070185E	500 hr	Amazon $35.19 eBay $30.00 FridayParts $45.99
Battery			0H3421S		Amazon eBay $283.32
Oil	SAE 30 (above 32°F), 10W-30 (40°F to -10°F), Synthetic 5W-30 (all temperatures)	3.55 liters	—	500 hr
Spark plug			RC12YC	1000 hr	Amazon $19.99 eBay $12.90 FridayParts $19.99

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

Service intervals

Item	Action	Hours	Months	Notes
Oil level	Check	24 hr	1 mo	Monthly or 24 hours of continuous operation
Aceite del motor	Change	25 hr		First service — Después del período de asentamiento de 25 horas, se recomienda utilizar el aceite 5W-20 propiedad de Generac para uso continuo.
Oil	Change	200 hr	24 mo	First service — After the first 25 hours of operation
Oil and filter	Change	25 hr		First service — After first 25 hours of operation
Oil filter	Change	200 hr	24 mo	First service — After the first 25 hours of operation
Valve Clearance	Check	400 hr	6 mo	First service — Check/adjust after first 25 hours of operation
Engine oil and filter	Replace	100 hr	12 mo	First service — After first 25 hours; then every 100 hours or 1 year. Cold weather (<4.4°C) or continuous hot (>29.4°C): every 100 hours or 1 year
Aceite de motor y filtro de aceite	Change	200 hr	24 mo	First service — Programa de mantenimiento A
Air cleaner	Replace	200 hr	24 mo	2Y or 200 hours
Batería (condición, nivel de electrolito y estado de carga)	Check	200 hr	24 mo	Programa de mantenimiento A
Battery condition and charge	Check	200 hr	24 mo	Schedule A maintenance
Complete Tune-Up	Other	200 hr	24 mo	To be completed by a Dealer; 2 years or 200 hours
Engine oil and oil filter	Replace	200 hr	24 mo	First service — Schedule A (Every Two Years or 200 Hours) and Schedule B (Every Four Years or 400 Hours). Change engine oil and filter after first 25 hours. In cold weather (below 40 F / 4.4 C) or continuous hot weather (above 85 F / 29.4 C), change every year or 100 hours.
Huile à moteur et filtre à huile	Change	200 hr	24 mo	First service — Calendrier A: tous les deux ans ou toutes les 200 heures. Changer l'huile et le filtre après les 25 premières heures. En conditions froides (moins de 4,4 °C/40 °F) ou fonctionnant en continu à plus de 29,4 °C/85 °F, changer annuellement ou toutes les 100 heures.
Óleo lubrificante e filtro de óleo	Change	200 hr	24 mo	First service — Trocar após as primeiras 25 horas; Programação A (2 anos ou 200 h); em clima frio (<4,4 °C) ou quente contínuo (>29,4 °C) anualmente ou 100 h
Aceite del motor y filtro de aceite	Replace	400 hr	48 mo	First service — Programa B: cada cuatro años o 400 horas.
Air cleaner	Clean	400 hr		Clean or replace as necessary; R = Replace as Necessary; 400 hours
Air cleaner	Inspect	400 hr	24 mo	Inspect and change; every 400 hours
Air filter	Replace	400 hr	48 mo	Schedule B maintenance
Bougies d'allumage	Clean	400 hr	48 mo	Nettoyer les bougies, vérifier l'écartement ou les remplacer. Calendrier A et Calendrier B.
Bujía(s)	Replace	400 hr	48 mo	Programa B: cada cuatro años o 400 horas.
Bujías	Replace	400 hr	48 mo	Programa B; limpiar, comprobar separación y sustituir
Engine air filter	Replace	1000 hr	48 mo	Schedule B. Emissions-critical.
Engine oil and oil filter	Change	400 hr	48 mo	First service — Schedule B (every four years or 400 hours).
Filtre à air du moteur	Replace	400 hr	48 mo	Calendrier B: tous les quatre ans ou toutes les 400 heures.
Filtro de aire del motor	Replace	400 hr	48 mo	Programa de mantenimiento B
Filtro de ar do motor	Replace	400 hr	48 mo	Programação B (4 anos ou 400 h)
Folga da válvula	Adjust	400 hr	48 mo	First service — Inspecionar/ajustar após as primeiras 25 h e depois a cada 400 h; Programação B; exclui 14/18 kW com motor 816 cc
Jeu des soupapes	Adjust	400 hr		First service — Vérifier et régler après les 25 premières heures de fonctionnement, puis toutes les 400 heures.
Luz de válvulas	Adjust	400 hr	48 mo	First service — Programa B; inspeccionar/ajustar cada 400 horas
Sediment trap	Clean	400 hr	48 mo	Schedule B maintenance
Separación de la válvula	Adjust	400 hr	48 mo	First service — Programa B. Inspeccione y ajuste después de las primeras 25 horas y luego cada 400 horas. No necesario en unidades 14/18 kW con motor 816 cc.
Spark plug(s)	Clean	400 hr		Replace every 4 years or 400 hours
Spark plug(s)	Inspect	400 hr	48 mo	Schedule B maintenance; clean, inspect gap, replace if necessary
Spark plug(s)	Replace	400 hr	48 mo	Schedule B. Emissions-critical.
Valve clearance	Adjust	1000 hr	48 mo	First service — Schedule B; inspect/adjust valve clearance after first 25 hours of operation, then at 400 hour intervals. Where applicable; excludes units with hydraulic lifters (14 or 18 kW with 816cc engine).
Vela(s) de ignição	Replace	400 hr	48 mo	Programação B (4 anos ou 400 h)
AVR Filter	Replace	500 hr	24 mo	Schedule A; replace more frequently in dusty conditions
Battery Condition and Electrolyte Level	Check	500 hr	24 mo
Engine Oil Filter and Oil	Replace	500 hr	24 mo	First service — Schedule A, every two years or 500 hours

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
Gap	Folga da vela de ignição	0,020	pol
Gap	Folga da vela de ignição	0,040	pol
Gap	Folga da vela de ignição	0,508	mm
Gap	Folga da vela de ignição	1,02	mm
Gap	Ignition magneto air gap	0.008-0.012 inch (0.20-0.30 mm)	gap	V-twin engines; fixed non-adjustable on single cylinder
Gap	Separación de electrodos de bujía (11 kW)	0.030	in (0.76 mm)
Gap	Separación de electrodos de bujía (16/20/22 kW)	0.040	in (1.02 mm)
Gap	Separación de electrodos de bujía (9 kW)	0.020	in (0.508 mm)
Gap	Separación de las bujías	0.508	mm (0.020 pulg.)
Gap	Separación de las bujías	1.02	mm (0.040 pulg.)
Gap	Spark Plug Gap	0.020	in (0.508 mm)	9 kW (GH-426)
Gap	Spark Plug Gap	0.030	in (0.76 mm)	11 kW (GTH-530)
Gap	Spark Plug Gap	0.040	in. (1.02 mm)
Gap	Spark plug gap	0.508	mm
Gap	Spark plug gap	0.76	mm (0.030 in)	8, 11, and 20kW units
Gap	Spark plug gap	0.76 mm (0.030 inch)	gap	410 cc and 530 cc engines
Gap	Spark plug gap	1.02	mm (0.040 in)	13, 14, 15, 16, 17kW units
Gap	Spark plug gap	1.02 mm (0.040 inch)	gap	990 cc and 999 cc engines
Gap	Spark plug gap (10 kW)	0.020	in (0.508 mm)
Gap	Spark plug gap (11 kW)	0.030	in (0.76 mm)
Gap	Spark plug gap (14-24 kW)	0.040	in (1.02 mm)
Gap	Spark plug gap (16/20/22 kW)	0.040	in (1.02 mm)
Gap	Spark plug gap (9 kW)	0.020	in (0.508 mm)
Gap	Écartement des électrodes des bougies d'allumage	0.508	mm (0,020 po)
Gap	Écartement des électrodes des bougies d'allumage	0.76	mm (0,030 po)
Gap	Écartement des électrodes des bougies d'allumage	1.02	mm (0,040 po)
Other	Compression Ratio GH-410	8.6:1
Other	Compression Ratio GT-530	9.5:1
Other	Compression Ratio GT-990	9.5:1
Other	Compression Ratio GT-999	9.5:1
Other	Exercise time length (16-22 kW)	5	minutes
Other	Exercise time length (9-11 kW)	12	minutes
Other	Fusível do painel de controle	7,5	A
Other	Ordem de partida (10 kW)	15 s de arranque, 7 s de repouso, seguidos por quatro ciclos adicionais de 7 s de arranque e 7 s de repouso		cinco ciclos de manivela
Other	Ordem de partida (14 a 24 kW)	16 s de arranque, 7 s de repouso, 16 s de arranque, 7 s de repouso, seguidos por três ciclos adicionais de 7 s de arranque e 7 s de repouso		cinco ciclos de manivela
Other	Perda de potência do motor por altitude	3,5	% a cada 304,8 m (1.000 pés) acima do nível do mar
Other	Perda de potência do motor por temperatura	1	% a cada 6 °C (10 °F) acima de 15 °C (60 °F)
Other	Rated Horsepower @ 3,600 rpm GH-410	14.8	HP
Other	Rated Horsepower @ 3,600 rpm GT-530	18	HP
Other	Rated Horsepower @ 3,600 rpm GT-990	32	HP
Other	Rated Horsepower @ 3,600 rpm GT-999	36	HP
Other	Redução de classificação GN vs PL	10 a 20	%
Other	Retardo de calentamiento con Arranque inteligente en frío	30	segundos	temperatura ambiente por debajo de la temperatura fijada
Other	Retardo de calentamiento normal	6	segundos	temperatura ambiente en o sobre la temperatura fijada
Other	Starter motor performance, V-twin	Minimum rpm 3250; Maximum Amps 62
Other	Starter motor performance, single cylinder	Minimum rpm 4500; Maximum Amps 9
Other	Tamanho mínimo de tanque de PL ao converter de GN	946	L (250 gal)
Other	Utility failure detection threshold	65	% of nominal (for five consecutive seconds)
Other	Utility restoration threshold	80	% of nominal (for 15 consecutive seconds)
Pressure	Cylinder leak down tester regulated pressure	80	psi	air source at least 90 psi
Pressure	Fuel pressure (Liquid Propane)	10-12	in water column (2.49-2.99 kPa)	at generator fuel inlet
Pressure	Fuel pressure (Natural Gas)	3.5-7.0	in water column (0.87-1.74 kPa)	at generator fuel inlet
Pressure	Fuel pressure LP	10 to 12	inches water column	required
Pressure	Fuel pressure at regulator - LP	10-12	in water column (19-22 mm Hg)
Pressure	Fuel pressure at regulator - Natural Gas	3.5-7.0	in water column (9-13 mm Hg)
Pressure	Fuel pressure natural gas	5 to 7	inches water column	required
Pressure	Fuel pressure to regulator (LP)	10-12	in water column (19-22 mm Hg)	LP gas
Pressure	Fuel pressure to regulator (NG)	3.5-7.0	in water column (9-13 mm Hg)	natural gas
Pressure	Fuel pressure to regulator (natural gas)	3.5-7	inches water column (7-13 mm mercury)
Pressure	Fuel pressure to regulator - LP	10-12	inches water column (19-22 mm mercury)

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	Capacity	Notes
Engine oil	30 weight organic oil (factory fill)				Units run and tested at factory prior to shipping, no break-in required
Engine oil	5W-20				Aceite 5W-20 propiedad de Generac para uso continuo, después del período de asentamiento de 25 horas.
Engine oil	5W-20 (Generac proprietary)	API Service Class SJ, SL, or better		1.03 L	Oil capacity including filter. Use for continuous use after the 25 hour break-in period; specifically formulated for gaseous powered Generac generators. Do not use special additives. Change every year or 100 hours in cold weather (below 40 F) or continuous hot weather (above 85 F).
Engine oil	5W-30	Aceite orgánico 5W-30 (la unidad se entrega de fábrica llena con este aceite)			Compruebe el nivel de aceite y, de ser necesario, añada la cantidad apropiada con la viscosidad correcta. No llene en exceso. Consulte 'Recomendaciones para el aceite de motor' para tipo/viscosidad.
Engine oil	SAE 30 above 32°F; 10W-30 between 40°F and -10°F; Synthetic 5W-30 10°F and below	API Service Class SJ, SL or better; use no special additives		1.5 Qts	Oil capacity including filter
Engine oil	SAE 5W-30 Synthetic	API Service Class SJ, SL or better			Do not use special additives
Engine oil	SAE 5W-30 sintético	API SJ, SL o mejor		1.03 l	9 kW; no usar aditivos especiales
Engine oil	SAE 5W-30 synthétique	API classe de service SJ, SL ou supérieure			Huile SAE 5W-30 synthétique pour toutes les plages de température. N'utilisez aucun additif spécial.
Engine oil	Synthetic 5W-30	API SJ, SL or better			For all temperature ranges
Engine oil	Synthetic SAE 5W-30	API SJ, SL, or better		3.75 Quarts (3.55 Liters)	For all temperature ranges; do not use special additives
Engine oil	10W-30	API SJ, SL or better	-23°C to 4°C		Between 40ºF and -10ºF (4ºC and -23ºC)
Engine oil	SAE 30	API SJ, SL or better	above 0°C		Above 32ºF (0ºC)
Fuel		Gas natural: contenido de BTU de por lo menos 1000 BTU/ft3 (37,26 MJ/m3). Gas LP: por lo menos 2500 BTU/ft3 (93,15 MJ/m3)		250.0 gal (946 l)	Tamaño mínimo del tanque de LP es 250 gal (946 l), salvo que los cálculos de la unidad indiquen uno mayor. Solo sistema de extracción de vapor para LP.
Fuel	Gas natural	mínimo 1000 BTU por pie cúbico (37.26 megajulios por metro cúbico)			Reducciones típicas de gas natural 10-20 % respecto a LP
Fuel	Gaz naturel			37.26 mégajoules par mètre cube (1 000 BTU par pied cube) minimum	Teneur en BTU minimale du gaz naturel.
Fuel	Gaz naturel d'au moins 37,26 mégajoules par mètre cube (1 000 BTU par pied cube)	NFPA 54
Fuel	Gaz propane liquide (gazeux)			93.15 mégajoules par mètre cube (2 500 BTU par pied cube) minimum	Capacité de réservoir de gaz propane liquide minimum recommandée de 946 litres (250 gallons).
Fuel	Gaz propane liquide d'au moins 93,15 mégajoules par mètre cube (2 500 BTU par pied cube)	NFPA 58 / ICC IFGC			Réservoir de gaz propane liquide d'une capacité minimale de 946 litres (250 gallons).
Fuel	LP (vapor)	mínimo 2500 BTU por pie cúbico (93.15 megajulios por metro cúbico)		946.0 l	Se recomienda tanque de LP de 250 gal. (946 l) de tamaño mínimo si se convierte de NG a LP
Fuel	LP Gas (vapor), min 2500 BTU/ft3 (93.15 MJ/m3)				Minimum LP tank size 250 gal (946 L) recommended when converting
Fuel	Liquid Propane (LP) Vapor	Btu content at least 2,520 Btus per cubic foot; pressure 10-12 inches water column (0.36-0.43 psi)			Use vapor withdrawal system only
Fuel	Liquid Propane (LP) vapor withdrawn or pipeline Natural Gas				NG min 1000 BTU/cu ft (37.26 MJ/m3); LP min 2500 BTU/cu ft (93.15 MJ/m3); min LP tank size 250 gal (946 L) recommended if converting from NG
Fuel	Liquid Propane (vapor)			2500.0 BTU/ft3 (93.15 MJ/m3) minimum	Vapor withdrawn; minimum tank size 250 gal (946 L) when converting from NG
Fuel	Liquid Propane Vapor (LP)			946.0 liters	Minimum 2,500 Btus per cubic foot (93.15 megajoules per cubic meter). Minimum tank size 250 gallons (946 liters) recommended for conversion.
Fuel	Liquid propane (LP) gas (vapor)	at least 2,500 Btus per cubic foot (93.15 megajoules per cubic meter)		250.0 gallons (946 liters)	Minimum LP tank size recommended when converting from natural gas
Fuel	Liquid propane (LP) vapor	BTU content at least 2,500 BTUs per ft3 (93.15 megajoules per m3)			If converting to LP gas from NG, a minimum LP tank size of 250 gal (946 L) is recommended.
Fuel	Natural Gas				Minimum 1,000 Btus per cubic foot (37.26 megajoules per cubic meter). Factory set default fuel.
Fuel	Natural Gas, min 1000 BTU/ft3 (37.26 MJ/m3)				Factory set to run on natural gas
Fuel	Natural gas (NG)	BTU content at least 1,000 BTUs per ft3 (37.26 megajoules per m3)			Unit factory-configured to run on NG.
Fuel	Natural gas (pipeline)	at least 1,000 Btus per cubic foot (37.26 megajoules per cubic meter)			Unit is factory set to run on natural gas

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
1048	VSCF Overload	Unit shuts down during operation	Shutdown	Alternator, AVR or wiring damaged. Contact servicing dealer.
1049	VSCF Overload	Unit shuts down during operation	Shutdown	Generator output shorted or severely overloaded; clear overload and restart
1051	VSCF High Battery	Yellow LED illuminated in any state	Warning	Voltage supply to AVR is high; check external battery charger installation or contact servicing dealer
1052	VSCF DC Overvoltage	Unit shuts down during operation	Shutdown	Generator temporarily overloaded or output shorted; try restart
1053	VSCF Gate Fault	Unit shuts down during operation or starting	Shutdown	AVR is damaged; contact servicing dealer
1054	VSCF IGBT Overtemp.	Unit shuts down during operation or starting	Shutdown	Replace AVR filter, inspect fan, check intake/exhaust, check ambient temperature; contact servicing dealer
1055	VSCF Phase Error	Unit shuts down during starting	Shutdown	Check stepper motor, linkage, gas pressure; contact servicing dealer if alternator damaged
1056	VSCF Undervoltage	Unit shuts down during operation or starting	Shutdown	Load too large, remove and restart; or alternator/AVR damage, contact servicing dealer
1057	VSCF Overvoltage	Unit shuts down during operation or starting	Shutdown	Generator overloaded; remove load and restart
1058	VSCF DC Undervoltage	Unit shuts down during operation or starting	Shutdown	Alternator damage; contact servicing dealer
1059	VSCF Field Loss	Unit shuts down during starting	Shutdown	Alternator damage; contact servicing dealer
1060	Big Fan Failure	Unit shuts down during operation	Shutdown	AVR electronics exceeded 70°C; replace AVR filter, check intake/exhaust/ambient temp; contact servicing dealer
1061	VSCF Field Loss	Unit shuts down during operation	Shutdown	Alternator damage; contact servicing dealer
1065	Overfrequency	Unit shuts down during operation	Shutdown	Overload, RPM sensor failure, or stepper motor problem; contact servicing dealer
1066	VSCF Speed mismatch	Unit shuts down during operation or starting	Shutdown	Fuel pressure loss, large overload, or throttle/engine problem; contact servicing dealer
1070	Small fan failure	Small fan failure displayed; continues 80 minutes without fan if running in AUTO	Warning	Check fan wiring/mechanical, check AVR filter for blocked air path
ADVERTENCIA DEL CARGADOR	ADVERTENCIA DEL CARGADOR	Indicador LED amarillo encendido en cualquier estado.	Warning	Comuníquese con un IASD.
AUXILIARY SHUTDOWN	Desligamento auxiliar	A unidade não inicia.	Shutdown	Coloque as chaves de parada auxiliares em FECHADO (I). Apague o alarme.
BAJA PRESIÓN DEL ACEITE	BAJA PRESIÓN DEL ACEITE	La unidad no arranca en AUTO con una pérdida de energía eléctrica.	Shutdown	Revise el nivel de aceite y reponga si es necesario. Si el nivel de aceite es correcto, comuníquese con un IASD.
BAJA VELOCIDAD	BAJA VELOCIDAD	La unidad no arranca en AUTO con una pérdida de energía eléctrica.	Shutdown	Comuníquese con un IASD.
BATERÍA BAJA	BATERÍA BAJA	Indicador LED amarillo encendido en cualquier estado.	Warning	Borre la alarma. Navegue hasta BATTERY MENU del MAIN MENU para revisar la batería. Si indica GOOD, comuníquese con un IASD. Si indica CHECK BATTERY, reemplace la batería.
BATTERY PROBLEM	Problema de batería	Yellow LED illuminated in any state.	Warning	Entre em contato com uma IASD.
Battery Problem	Battery Fault	Battery condition poor or battery charger issue	Warning	Inspect battery condition and connections. Contact IASD if needed.
CARGADOR SIN CA	CARGADOR SIN CA	Indicador LED amarillo encendido en cualquier estado.	Warning	Comuníquese con un IASD.
CHARGER MISSING AC	Charger Missing AC	LED amarelo aceso em qualquer estado.	Warning	Restore AC power supply or check generator AC output.
CHARGER WARNING	Charger Warning	Yellow LED illuminated in any state.	Warning	Entre em contato com uma IASD.
CONTROLLER FAULT	Anomalia no controlador	Falha do controlador.	Shutdown	Entre em contato com uma IASD.
Controller Fault	Control Module Failure	Internal controller fault detected	Shutdown	Contact IASD for assistance
DESCONEXIÓN AUXILIAR	DESCONEXIÓN AUXILIAR	La unidad no arranca.	Shutdown	Coloque los interruptores de desconexión auxiliar en posición CERRADA (I).
DOWNLOAD FAILURE	Falha na importação	Firmware download or update failed	Warning	Verifique o ficheiro e tente novamente.
EMERGENCY STOP	Paragem de emergência	Paragem de emergência ativada.	Shutdown	Entre em contato com uma IASD.
ERROR DE CABLEADO	ERROR DE CABLEADO	La unidad no arranca en AUTO con una pérdida de energía eléctrica.	Shutdown	Comuníquese con un IASD.
EXERCISE SET ERROR	Exercise Set Error	Exercise timer setting error	Warning	Entre em contato com uma IASD.
FALLA DE ARRANQUE	FALLA DE ARRANQUE	La unidad no arranca en AUTO con una pérdida de energía eléctrica.	Shutdown	Verifique que la válvula de cierre de la tubería de combustible esté en la posición ON. Borre la alarma. Arranque la unidad en MANUAL. Si no arranca o funciona de forma dificultosa, comuníquese con un IASD.
FIRMWARE ERROR-7	Erro de firmware 7	Erro de firmware.	Shutdown	Entre em contato com uma IASD.
FIRMWARE ERROR-9	Erro de firmware 9	Erro de firmware.	Shutdown	Entre em contato com uma IASD.
FUEL PRESSURE	Fuel Pressure	Fuel pressure warning	Warning
FUSE PROBLEM	Problema de fusible	Unit will not start in AUTO with utility loss. (Firmware 1.11 and older only.)	Warning	Comprobar el fusible de 7.5 A; sustituir con fusible ATO de 7.5 A si está fundido, o contactar un IASD
HIGH TEMPERATURE	Temperatura elevada	Unit shuts down during operation.	Shutdown	Inspecione a ventilação ao redor do gerador, admissão, exaustão e parte traseira. Se não existirem obstruções, entre em contato com uma IASD.
High Temperature	Overheat	Engine operating temperature too high	Shutdown	Inspect ventilation around generator, intake, exhaust, and rear. Ensure no obstructions present.
INSPECCIONE LA BATERÍA	INSPECCIONE LA BATERÍA	Indicador LED amarillo encendido en cualquier estado.	Warning	Inspeccione la batería. Presione ENTER para borrar.
INSPECT BATTERY	Inspect Battery	Yellow LED illuminated in any state.	Warning	Inspect battery; press ENTER to clear.
INTERNAL FAULT	Internal Fault	Internal controller fault	Shutdown	Contact servicing dealer.
LOW BATTERY	Low Battery Alarm	Yellow LED illuminated in any state.	Warning	Desactivar la alarma; comprobar batería en BATTERY MENU; si GOOD contactar un IASD, si CHECK BATTERY sustituir la batería
LOW OIL PRESSURE	Pressão de óleo baixa	Unit will not start in AUTO with utility loss.	Shutdown	Verifique o nível de óleo e adicione óleo se necessário. Se o nível estiver correto, entre em contato com uma IASD.
LOW VOLTS REMOVE LOAD	Voltaje bajo, retirar carga	Unit will not start in AUTO with utility loss.	Warning	Desactivar la alarma, retirar cargas domésticas, poner en AUTO y reanudar
Low Battery	Battery Voltage Low	Starting battery voltage below acceptable level	Warning	Inspect battery and battery cables. Charge or replace battery if necessary.
Low Oil Pressure	Low Oil Level or Pressure	Insufficient oil pressure in engine	Shutdown	Check engine oil level and top up if necessary. Contact IASD if problem persists.
MISWIRE	Miswire / Wiring Error	Unit will not start in AUTO with utility loss.	Shutdown	Contactar un IASD
NINGUNA	NINGUNA (LED verde parpadeando)	La unidad funciona en AUTO, pero no energiza la casa.	Info	Revise el MLCB del generador (desconexión del generador). Si está encendido, comuníquese con un IASD.
NO ACTIVADA	NO ACTIVADA	La unidad no arranca en AUTO con una pérdida de energía eléctrica.	Info	Verifique si la pantalla indica que la unidad no está activada. Consulte Activación.
NOT ACTIVATED	Não ativado	Unit will not start in AUTO with utility loss.	Warning	Refer to activation section in owners manual
OVER VOLTAGE	Over Voltage	Overvoltage alarm	Shutdown	Contact servicing dealer.
OVERCRANK	Overcrank Alarm	Unit will not start in AUTO with utility loss.	Shutdown	Verify fuel line shutoff valve is ON. Clear alarm. Start unit in MANUAL. If it does not start or starts rough, contact IASD.
OVERLOAD	Overload	Load current exceeds generator rated capacity	Shutdown	Clear alarm and remove household loads from the generator. Put back in AUTO and restart.
OVERLOAD REMOVE LOAD	Sobrecarga, retirar carga	Unit shuts down during operation.	Shutdown	Desactivar la alarma, retirar cargas domésticas, poner en AUTO y volver a poner en marcha
OVERLOAD WARNING	Overload Warning	Overload warning	Warning	Remova as cargas domésticas do gerador.
OVERSPEED	Sobrevelocidad	Unit will not start in AUTO with utility loss.	Shutdown	Entre em contato com uma IASD.
OVERVOLTAGE	Tensão excessiva	Unit will not start in AUTO with utility loss.	Shutdown	Entre em contato com uma IASD.
Overcrank	Extended Cranking	Engine failing to start after extended crank attempts	Shutdown	Check fuel supply, spark plugs, and fuel system. Contact IASD for further diagnosis.
Overload	Overload Detected	Electrical load exceeds generator capacity	Shutdown	Remove household electrical loads from generator
Overspeed	RPM Overspeed	Engine running at excessive RPM	Shutdown	Contact IASD for assistance
Overvoltage	Output Voltage High	Generator voltage exceeding nominal rating	Shutdown	Reduce electrical load and restart. Contact IASD if issue persists.
PROBLEMA DE BATERÍA	PROBLEMA DE BATERÍA	Indicador LED amarillo encendido en cualquier estado.	Warning	Comuníquese con un IASD.
PÉRDIDA DE DETECCIÓN DE RPM	PÉRDIDA DE DETECCIÓN DE RPM	La unidad funcionaba, se apagó e intenta reiniciarse, o no arranca en AUTO con una pérdida de energía eléctrica.	Shutdown	Borre la alarma y retire del generador las cargas del hogar. Vuelva a poner en AUTO y reinicie. Si el generador no arranca, comuníquese con un IASD.
RPM SENSE LOSS	RPM Sense Loss Alarm	Unit was running and shuts down, attempts to restart	Shutdown	Desactivar la alarma, retirar cargas, poner en AUTO y reanudar; si no arranca contactar un IASD
RPM SENSOR LOSS	RPM Sensor Loss	Engine speed sensor failure or loss of RPM signal	Shutdown	Clear alarm and remove household loads from generator. Set back to AUTO and restart. If alarm returns, contact servicing dealer to investigate possible fuel issue.
RPM Sensor Loss	RPM Signal Loss	RPM sensor signal not detected	Shutdown	Contact IASD for assistance
SERVICE A	Servicio A	Yellow LED illuminated, maintenance due	Warning	Realize a manutenção SERVICE A. Pressione ENTER para apagar.
SERVICE B	Servicio B	Yellow LED illuminated, maintenance due	Warning	Realize a manutenção SERVICE B. Pressione ENTER para apagar.
SERVICIO A	SERVICIO A	Indicador LED amarillo encendido en cualquier estado.	Warning	Realice el mantenimiento SERVICIO A. Presione ENTER para borrar.
SERVICIO B	SERVICIO B	Indicador LED amarillo encendido en cualquier estado.	Warning	Realice el mantenimiento SERVICIO B. Presione ENTER para borrar.
SOBRECARGA. RETIRE LA CARGA	SOBRECARGA	La unidad se apaga durante el funcionamiento.	Shutdown	Borre la alarma y retire del generador las cargas del hogar. Vuelva a poner en AUTO y reinicie.
SOBRECORRIENTE DEL MOTOR DE VELOCIDAD GRADUAL	SOBRECORRIENTE DEL MOTOR DE VELOCIDAD GRADUAL	La unidad no arranca en AUTO con una pérdida de energía eléctrica.	Shutdown	Comuníquese con un IASD.
SOBREVELOCIDAD	SOBREVELOCIDAD	La unidad no arranca en AUTO con una pérdida de energía eléctrica.	Shutdown	Comuníquese con un IASD.
SOBREVOLTAJE	SOBREVOLTAJE	La unidad no arranca en AUTO con una pérdida de energía eléctrica.	Shutdown	Comuníquese con un IASD.
STEPPER OVER CURRENT	Stepper Over Current	Stepper motor over current	Shutdown	Contact servicing dealer.
STEPPER OVERCURRENT	Stepper Overcurrent	Unit will not start in AUTO with utility loss.	Shutdown	Entre em contato com uma IASD.
SUBVOLTAJE	SUBVOLTAJE	La unidad no arranca en AUTO con una pérdida de energía eléctrica.	Shutdown	Comuníquese con un IASD.
TEMPERATURA ALTA	TEMPERATURA ALTA	La unidad se apaga durante el funcionamiento.	Shutdown	Inspeccione la ventilación alrededor del generador, además de las secciones de entrada, escape y trasera. Si no hay obstrucciones, comuníquese con un IASD.

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

Procedures

Adjust Valve Clearance adjustment

⚠ Allow engine to cool before adjusting valve clearance

⚠ AVR fan operates for 80 minutes after shutdown

Tools: 13mm wrench, 10mm Allen wrench, Feeler gauge

Remove spark plug wires and spark plugs
Remove four screws attaching valve cover, discard gasket
Verify piston at top dead center (TDC) of compression stroke
Loosen rocker jam nut with 13mm wrench
Turn pivot ball stud with 10mm Allen wrench while checking clearance with feeler gauge
Tighten jam nut to 174 in-lbs (19.68 Nm) while holding pivot ball stud
Recheck valve clearance
Install new valve cover gasket and valve cover, torque fasteners to 60 in-lbs (6.8 Nm) in cross pattern
Install spark plugs, torque to 18 ft-lbs (25 Nm)
Connect AVR fan and 4-pin connector
Install AVR filter housing, torque to 50-96 in-lbs (6-11 Nm)
Repeat for other cylinder if necessary

Adjusting Magneto Flywheel Gap adjustment

⚠ Air gap between ignition magneto and flywheel on single cylinder engines is not adjustable.

Tools: 0.008-0.012 inch thickness gauge

Rotate the flywheel until the magnet is under the module (armature) laminations.
Place a 0.008-0.012 inch (0.20-0.30mm) thickness gauge between flywheel magnet and module laminations.
Loosen the mounting screws and let the magnet pull the magneto down against the thickness gauge.
Tighten both mounting screws.
To remove the thickness gauge, rotate the flywheel.
Repeat the above procedure for the second magneto.

Adjusting Valve Clearance adjustment

⚠ Risk of Burn. Allow the engine to cool before performing the following procedure.

Tools: feeler gauge, 10 mm wrench, 13 mm wrench, 14 mm wrench, 10 mm hex key

Remove spark plug wire(s) and position away from spark plug(s).
Remove spark plug(s).
Remove the four screws attaching valve cover. Remove and discard gasket.
Verify piston is at TDC of its compression stroke (both valves closed).
Loosen rocker jam nut using a 10 mm wrench (10 kW units) or 13 mm wrench (20-24 kW units).
Turn pivot ball stud using a 14 mm wrench (10 kW) or 10 mm hex key (20-24 kW) while checking clearance with a feeler gauge.
Hold pivot ball stud and tighten rocker arm jam nut.
Inspect valve clearance to verify it did not change.
Install new valve cover gasket and valve cover; tighten fasteners in a cross pattern.
Install spark plug(s) and tighten to 18 ft-lbs (25 Nm); attach spark plug wires.
Repeat process for other cylinder if equipped.

Adjusting the Fuel Regulator - 7kW (Natural Gas Only) adjustment

⚠ Do not make any unnecessary adjustments. Factory settings are correct for most applications.

Tools: frequency meter

Start the generator; let it stabilize and warm up at no-load.
Connect a frequency meter across the generator's AC output leads.
Turn the primary adjust screw to obtain a frequency reading.

Ajustar a folga das válvulas adjustment

⚠ Risco de queimaduras. Deixe o motor esfriar antes de executar o procedimento.

Tools: Chave de 10 mm, Chave de 13 mm, Chave de 14 mm, Chave sextavada de 10 mm, Calibrador

Remova os fios das velas de ignição e remova as velas de ignição.
Remova os quatro parafusos que prendem a tampa da válvula; descarte a junta.
Verifique se o pistão está no TDC do seu curso de compressão.
Solte a contraporca do balanceiro (C) com chave de 10 mm ou 13 mm.
Gire o pino de esfera articulada (D) com chave de 14 mm ou sextavada de 10 mm e ajuste a folga.
Aperte a contraporca do braço oscilante e inspecione a folga novamente.
Instale a nova junta e as tampas das válvulas; aperte em padrão transversal.
Instale as velas e aperte a 25 Nm; conecte os fios das velas.

Ajuste de la luz de válvulas adjustment

⚠ Dejar enfriar el motor antes de ajustar.

⚠ Iniciar los cuatro tornillos antes de apretar.

Tools: Calibre de espesores, Llaves de 8/10/13/14 mm, Llave de casquillo, Casquillo grande

Cerrar la válvula de combustible y desconectar la batería.
Retirar cable(s) de bujía y alejarlos.
Retirar la(s) bujía(s).
Llevar el pistón al PMS de la carrera de compresión.
Retirar los cuatro tornillos de la cubierta de válvulas y desechar la junta.
Aflojar la contratuerca del balancín.
Girar el prisionero de bola pivote para ajustar la luz con calibre.
Sostener el prisionero y apretar la contratuerca; verificar y reinstalar con junta nueva.

Ajuste de la separación de la válvula adjustment

⚠ Deje que el motor se enfríe antes del procedimiento.

⚠ Desconecte el cable negativo y luego el positivo de la batería.

⚠ No necesario en unidades 14 o 18 kW con motor de 816 cc.

Tools: Llave de 10 mm, Llave de 13 mm, Llave de 14 mm, Llave hexagonal de 10 mm, Galga de espesores

Retire los hilos de las bujías y las bujías.
Retire los cuatro tornillos de la cubierta de la válvula y deseche la junta.
Verifique que el pistón esté en el PMS de su carrera de compresión.
Suelte la contratuerca del balancín (llave 10 mm en 10 kW, 13 mm en 20 a 24 kW).
Gire el espárrago del pivote (llave 14 mm en 10 kW, hexagonal 10 mm en 20 a 24 kW) ajustando la separación.
Sostenga el espárrago y apriete la contratuerca del balancín.
Inspeccione la separación para verificar que no cambió.
Instale una junta nueva y la cubierta de la válvula; apriete en patrón cruzado.
Instale las bujías y apriete a 25 Nm (18 lb-pie).
Conecte los hilos de las bujías.

Check and Adjust Engine Governor (Single Cylinder Units) adjustment

Tools: Frequency meter, torque wrench

Loosen the governor clamp bolt.
Hold the governor lever at wide open throttle position.
Rotate the governor shaft clockwise as far as it will go.
Tighten the governor lever clamp bolt to 70 inch-pounds (8 N-m).
Start the generator; let it stabilize and warm up at no-load.
Connect a frequency meter across the generator AC output leads.
Turn the primary adjust screw to obtain a frequency of 61.5 Hz.
Turn the secondary adjust screw to obtain a frequency of 62.5 Hz.

Check and Adjust Valves adjustment

Tools: 10mm allen wrench, flat feeler gauge, torque wrench

Remove the four (4) screws from the rocker cover.
Remove the rocker cover and rocker cover gasket.
Loosen the rocker arm jam nut.
Use a 10mm allen wrench to turn the pivot ball stud.
Check clearance between rocker arm and valve stem with a flat feeler gauge.
Set valve clearance to 0.05-0.1mm (0.002-0.004 in.) cold.
Hold pivot ball stud with allen wrench and tighten rocker arm jam nut to 174 inch pounds.
Recheck valve clearance to make sure it did not change.
Re-install rocker cover gasket, rocker cover and the four screws.

Conversion de carburant adjustment

⚠ Explosion et incendie. Le carburant et ses vapeurs sont extrêmement inflammables et explosifs.

Localiser le bouton orange de conversion (A).
Tourner le bouton vers la flèche indiquant la source de carburant jusqu'à l'arrêt.
Le bouton tourne sur 180° et glisse dans le corps du mélangeur pour le propane liquide.
Saisir la sélection du carburant (PL ou GN) sur l'automate de contrôle (Assistant d'installation ou menu EDIT > Fuel Selection).

Conversión de combustible adjustment

⚠ Explosiones e incendio: no se permiten fugas de combustible.

Ubique la perilla naranja de conversión de combustible (debajo del mezclador en 9 kW, sobre el mezclador en 11 kW–22 kW).
Gire la válvula hacia la marca de flecha de la fuente de combustible hasta que se detenga.
Introduzca la selección de combustible (LP/gas natural) en el controlador mediante el Asistente de instalación o el menú EDIT, 'Fuel Selection'.

Conversión de combustible (GN a PL) adjustment

⚠ La perilla del selector de combustible debe ajustarse al combustible correcto para que el generador funcione correctamente.

Ubique la perilla de conversión de combustible naranja (bajo el mezclador en 10 kW; sobre el mezclador en 14 a 24 kW).
Gire la perilla de conversión hacia la flecha del tipo de combustible marcado hasta que se detenga.
La perilla gira 180° y se desliza hacia dentro del mezclador al convertir a propano líquido.
Ingrese la selección de combustible (PL/GN) en el controlador mediante el Asistente de instalación o el menú EDITAR.

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
		0 – c.c. (-)	NOIR no 3	Fil de mise à la terre normal; obligatoire si jumelé à un commutateur de transfert de gestion intelligente de l'alimentation de Generac.
		23	BLANCO Núm. 5	Cable de señal lógica del control de transferencia
		23 (White #5)	E	Transfer Control Signal Wire
		Control system interconnections	N1, N2, 0, 15B, 23	Can be run in same conduit as AC power if length < 35 feet and all wiring rated 600V
		Longueur de fil 1 à 35 m (1 à 115 pi)	Calibre 18 AWG	Conducteurs en cuivre seulement.
		Longueur de fil 35 à 56 m (115 à 185 pi)	Calibre 16 AWG	Conducteurs en cuivre seulement.
		Longueur de fil 56 à 89 m (185 à 295 pi)	Calibre 14 AWG	Conducteurs en cuivre seulement.
		Longueur de fil 89 à 140 m (295 à 460 pi)	Calibre 12 AWG	Conducteurs en cuivre seulement.
		N1, N2, T1, Leads 23 and 194	All conductors rated for minimum 300V	Class 1 remote control/signaling circuits. Install per NEC Article 300 and recognized wiring methods. Sense wires through wire tie C1 to sense wire terminal block B. Control wires through wire tie C2 to control wire terminal block A.
	1	Connect a 2008 and later load center switch to a pre-2008 air-cooled generator: Wire 0 will not be utilized. Remove battery charger from the transfer switch. Connect N1 (BLU) to N1 (YEL), N2 (YEL) to N2 (YEL), 23 (BRN) to 23 (WHT), 194 (ORG) to 15B (RED) using UL approved wire nuts.	N1, N2, 23, 194, 15B, 0	Battery charger in transfer switch will not be utilized in operation of the generator.
	1	Connect a pre-2008 load center switch to a current or future air-cooled generator: Wire 0 will not be utilized. Connect N1 (BLU) to N1 (YEL), N2 (YEL) to N2 (YEL), 23 (BRN) to 23 (WHT), 194 (ORG) to 15B (RED) using UL approved wire nuts.	N1, N2, 23, 194, 15B, 0	Wire 194 changed to 15B on current model air-cooled generators.
0 VCC		0	NEGRO Núm. 3	CC (-) Cable común de conexión a tierra. Requerido si el generador está apareado con un interruptor de transferencia de gestión de alimentación inteligente Generac.
12 V c.c.		194 – c.c. (+)	ROUGE no 4	Pour les commandes de transfert.
12 VCC		194	ROJO núm. 4	CC (+) para los controles de transferencia
12 VDC		194 (Red #4)	D	DC (+) 12 VDC for Transfer Controls
120	1	Battery charger AC input to generator backed-up 120VAC circuit	120VAC hot, neutral	Connect via wire nuts
120 V c.a.		T1	BLEU no 3	Avec fusible 120 V c.a. pour le chargeur de la batterie; doit être branché pour que la batterie demeure chargée.
120 VAC		T1 (White #3)	B	Fused 120VAC for Battery Charger
120 VCA		T1	AZUL Núm. 3	Con fusible para el cargador de baterías (debe estar conectado para mantener la batería cargada, esté o no funcionando la unidad)
120/240	1	GENERATOR (STANDBY) source power cables to ATS GENERATOR supply terminals	E1, E2	200A models
120/240	1	Non-essential customer LOAD leads to LSS switch terminals	E1, E2	Load shed switch
120/240	1	UTILITY (NORMAL) power source cables to top of UTILITY SERVICE DISCONNECT circuit breaker	N1, N2	200A models
240	1	Transfer switch terminal lugs: connect utility source hot lines to N1 and N2; connect standby source hot lines (E1, E2) to E1 and E2; connect load lines from T1 and T2 to electrical load circuit; connect UTILITY, STANDBY and LOAD neutral lines to neutral block.	N1, N2, E1, E2, T1, T2	In 1-phase systems with a 2-pole transfer switch.
240 V c.a.		N1 et N2	JAUNE no 1 et no 2	Détectent les chutes et les hausses du réseau public.
240 VAC		N1 & N2 (Yellow #1 & #2)	A	Sensing for Utility Dropout and Pickup
240 VCA		N1 y N2	AMARILLO Núm. 1 y Núm. 2	Detección de desenganche y activación del servicio público
DC		0 (Black #3)	C	DC (-) Common Ground Wire

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

Common questions

What is the oil capacity of the Generac GT-999?

The Generac GT-999 engine has an oil capacity of 1.8 liters.

What is the displacement of the Generac GT-999?

The Generac GT-999 has a displacement of 0.999 liters with 2 cylinders.

Which generators use the Generac GT-999 engine?

The Generac GT-999 powers 3 generator set(s), including Generac 15 kW EcoGen, Generac 8.1 GN, Generac G0070420.

How often should you change the oil in the Generac GT-999?

The Generac GT-999 oil change interval is every 500 hours.

What is a common problem with the Generac GT-999 engine?

A commonly reported issue on generators using the Generac GT-999 is: DANGER.