Tohatsu M25H Troubleshooting
| Engine Model: Tohatsu M25H |
| Engine Type: 2-stroke 2-cylinder gasoline outboard engine |
| Total Displacement: 26.1 cu.in (429 cc) |
| Rated Engine Power: 25 Hp (18.4 kW) at 5500 rpm |
| Fuel System: Carburetor |
____________________________________________________________________________________
| Engine doesn't start or starts hard |
Empty fuel tank - Fill gasoline up.
Wrong fuel grade - Use correct gasoline grade.
Water or air in fuel system - Remove air or water from system.
Spark plug wire connection are damaged - Inspect the spark plug wire connection, replace or repair.
Defective spark plug - Spark plug need to be replaced.
Fuel filter is dirty - Change fuel filter.
Problems with carburetor adjustment - Adjust as required.
Clogged fuel lines - Clean fuel lines.
Fuel tank air vent restricted or closed - Fuel tank air vent need to be opened or cleaned.
Fuel pump pressure is low - Install new pump or repair it.
Reed valve is defective or worn - Install new reed valve.
Faulty spark plug - Install new spark plug.
Clogged or faulty carburetor - Service or change carburetor.
Faulty ignition coil - Change ignition coil as required.
Fuel tank air vent restricted or closed - Open or service air vent.
Low fuel pump pressure - Install new pump or repair it.
Defective ignition system - Check ignition and replace faulty components.
Fuel pump is clogged or faulty - Service or change fuel pump.
Problems with carburetor adjustment - Adjust as required.
Dirt in the fuel lines - Clean fuel lines.
Closed or clogged fuel tank air vent - Open or clean air vent.
Dirty fuel filter - Replace or clean fuel filter.
Gaskets are damaged - Replace gaskets.
Engine overloaded - Load reducing is recommended.
Too lean carburetor mixture - Set the carburetor properly.
Bad ignition timing - Set the ignition timing properly.
Damaged thermostat - Change thermostat.
Damaged water pump - Change water pump as required.
Improper propeller diameter or pitch - Replace propeller.
Damaged or improper size of propeller - Replace propeller.
Outboard motor is mounted too high or too low - Position the engine correctly.
Low octane gasoline - Change fuel.
Engine overload - Load reducing is recommended.
Wrong adjustment of low idle speed - Adjust idling as required.
Dirty or damaged fuel pump - Inspect fuel pump and change as required.
Main bearings or crankshaft failure - Change defective components as required.
Cylinder bore or piston rings are worn - Change faulty parts.
Clogged or improperly adjusted carburetor - Clean or properly adjust carburetor.
Fuel pump is defective or dirty - Clean or replace fuel pump.
Ignition system is defective - Check ignition and replace faulty components.
Gaskets are defective - Replace gaskets.
Damaged powerhead parts - Defective components need to be replaced.
Propeller pitch or diameter incorrect - Replace propeller.
Damaged or improper size of propeller - Replace propeller.
Outboard motor mounting height is set incorrectly - Check the outboard engine mounting height.
Incorrect trim angle - Adjust trim angle correctly.
| Engine uses too much fuel |
Improper adjustment of carburetor main jet - Adjust it correctly.
Spark plug is loose or faulty - Change or re-tighten spark plug.
Sleeve, piston, or rings are damaged - Replace defective parts as required.
Damaged or bent propeller - Replace propeller.
Damaged propeller shaft - Have propeller shaft replaced.
Weeds clogs the propeller - Remove and clean propeller.
Motor mounting bolt is loose - Tighten bolt.
Damaged or loose steering pivot Tighten or replace.
Low battery output voltage - Battery needs to be recharged.
Battery is draining quickly - Service charging system or replace battery.
Disconnected wires or corroded battery terminals - Connect wires properly or change terminals.
Starter motor is damaged - Change or repair starter.
____________________________________________________________________________________
| Outboard Engines Technical Specifications |
| Small Engines Technical Specifications |
| Car Engines Technical Specifications |
| Industrial Engines Technical Specifications |
