Why generators show "high fuel consumption": 21 documented causes and brand-specific fixes, compiled across 11 manufacturers.
Low engine temperature
2 brands- Atlas Copco: Check thermostat; Check water temperature with thermometer and replace, if necessary
- John Deere: Check thermostat; Check water temperature with thermometer and replace, if necessary
Injection pumps defective; Injection nozzles defective; Injection timing incorrect; Wrong type of fuel
2 brands- Engine Manuals - Mitsubushi: Disassemble and replace parts; Clean or repair injection nozzles; Readjust; Refill with correct type of fuel
- Mitsubishi: Disassemble and replace parts; Clean or repair injection nozzles; Readjust; Refill with correct type of fuel
Restriction air filter/cleaner or induction system, Fault in atomizers or atomizers of an incorrect type, Fault in cold start system, Wrong type or grade of fuel used, Restricted movement of engine speed control, Restriction in exhaust pipe, Engine temperature is too low, Incorrect valve tip clearances
1 brandImproper type of fuel Clogged or dirty air cleaner Engine overloaded Improper valve clearance Injection nozzles dirty Injection pump out of time Engine not at proper temperature
1 brand- Northern Lights: Use correct fuel for temperature. Service air cleaner. Reduce the electrical load. See your dealer. See your dealer. See your dealer. Check your thermostats. Check water temperature with thermometer and replace gauge if necessary.
Injection pump out of time
1 brand- Northern Lights: See your dealer
Improper type of fuel, Clogged or dirty air cleaner, Engine overload, Improper valve clearance, Injection nozzles dirty, Injection pump out of time, Engine not at proper temperature, Defective turbocharger
1 brand- Northern Lights: Use correct fuel for temperature, Service air cleaner, Reduce load, See your local dealer, See your local dealer, Check your thermostats, Check water temperature with thermometer and replace gauge if necessary, See you local dealer
Improper type of fuel, Clogged or dirty air cleaner, Improper valve clearance, Injection nozzles dirty, Injection pump out of time, Engine not at proper temperature
1 brand- Northern Lights: Use correct fuel for temperature, Service air cleaner, See your dealer, See your dealer, See your dealer, Check your thermostats, Check water temperature with thermometer and replace gauge if necessary
Injection pump defective Injection nozzles defective Injection timing incorrect Wrong type of fuel (low cetane number) Tank Compression pressure low Insufficient air (air cleaner clogged) Check turbocharger.
1 brand- Mitsubishi: Readjust or replace. Readjust or replace. Readjust. Refill with correct type of fuel. Disassemble and replace parts. Clean or change element.
Injection pump defective Injection nozzles defective Injection timing incorrect Wrong type of fuel Compression pressure low Insufficient air (air cleaner clogged)
1 brand- Mitsubishi: Readjust or replace. Readjust or replace. Readjust. Refill with correct type of fuel. Disassemble and replace parts. Clean or change air cleaner element.
Dirty Debris Screen, Incorrect Oil Level, Engine Overloaded
1 brandIncorrect Air/Fuel Ratio
1 brandRestriction in air filter/cleaner or induction system. Fault in atomisers or atomisers of an incorrect type. Fault in cold start system. Wrong type or grade of fuel used. Restricted movement of engine speed control. Restriction in exhaust pipe. Engine temperature is too low. Incorrect valve tip clearances.
1 brandRestriction in air filter/cleaner or induction system.; Fault in atomisers or atomisers of an incorrect type.; Fault in cold start system.; Wrong type or grade of fuel used.; Restricted movement of engine speed control.; Restricted exhaust pipe.
1 brandImproper type of fuel. Clogged or dirty air cleaner. Engine overloaded.
1 brand- John Deere: Use proper fuel. Service air cleaner. Reduce load.
Fuel feed pump defective
1 brand- Mitsubishi: Consult your Mitsubishi dealer.
Common questions
What causes high fuel consumption?
Common causes, most-reported first: Low engine temperature; Injection pumps defective; Injection nozzles defective; Injection timing incorrect; Wrong type of fuel; Restriction air filter/cleaner or induction system, Fault in atomizers or atomizers of an incorrect type, Fault in cold start system, Wrong type or grade of fuel used, Restricted movement of engine speed control, Restriction in exhaust pipe, Engine temperature is too low, Incorrect valve tip clearances; Improper type of fuel Clogged or dirty air cleaner Engine overloaded Improper valve clearance Injection nozzles dirty Injection pump out of time Engine not at proper temperature; Injection pump out of time; Improper type of fuel, Clogged or dirty air cleaner, Engine overload, Improper valve clearance, Injection nozzles dirty, Injection pump out of time, Engine not at proper temperature, Defective turbocharger.