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| Home / Engines / Briggs and Stratton Engines / Briggs and Stratton 31G777 |
Briggs and Stratton 31G777 Problems
| Engine Model: Briggs and Stratton 31G777 |
| Engine Type: 4-cycle single cylinder OHV vertical shaft gasoline engine |
| Total Displacement: 30.5 cu.in (500 cc) |
| Rated Engine Power: 17.5 Hp (13.0 kW) at 3300 rpm |
| Fuel System: Float type carburetor with fixed main jet |
| Engine doesn't start or hard to start |
Fuel tank is empty - Add fuel.
Incorrect fuel grade - Use correct fuel grade.
Air in the fuel pipes - Bleed the fuel pipes.
Loose or disconnected spark plug wire - Inspect the spark plug wire connection, replace or repair.
Damaged spark plug - Spark plug need to be replaced.
Fuel filter is dirty - Install new filter.
Faulty safety switch - Change damaged switch.
Carburetor is not adjusted - Check carburetor float adjustment.
Bad engine compression - Inspect cylinder block and replace worn components.
Worn or unadjusted choke cable - Replace cable or adjust correctly.
| Engine runs roughly |
Cooling fins are plugged - Need to wash or clean.
Ignition system malfunction - Check ignition and replace faulty components.
Defective or stuck throttle cable - Service or change the cable.
Plugged air filter - Service or change air filter.
Fuel pump is dirty or defective - Inspect fuel pump and change as required.
| Engine starts but then stops |
Defective spark plug - Install new spark plug.
Carburetor is defective or dirty - Service or repair carburetor.
Ignition coil is faulty - Ignition coil must be replaced.
Loose or worn valve springs - Change valve springs.
Stuck valves - Service the valves.
| Engine keeps overheating |
Insufficient engine oil - Fill up the engine oil.
Engine overload - Load reducing is recommended.
Cooling fins are plugged - Wash or clean as required.
Too lean carburetor mixture - Adjust carburetor correctly.
Bad ignition timing - Adjust ignition timing correctly.
Valve setting is incorrect - Set the valves properly.
| Abnormal engine knocking or noise |
Low octane gasoline - Use proper gasoline.
Engine overload - Load reducing is recommended.
Low engine oil level - Fill up the engine oil.
Incorrectly set low idle speed - Adjust idle speed.
Clogged or damaged fuel pump - Inspect fuel pump and change as required.
Crankshaft or main bearings failure - Worn parts replacement required.
Valve clearance is wrong - Adjust valve clearance according to specifications.
Piston rings or cylinder bore are damaged - Replace faulty components.
| Lack of engine power |
Carburetor is improperly adjusted or dirty - Clean or correctly adjust carburetor.
Air filter element is clogged - Clean or change air filter.
Clogged or defective fuel pump - Clean or install new fuel pump.
Defective ignition - Check ignition and replace faulty components.
Defective cylinder head gasket - Replace the head gasket.
Valves are burned or stuck - Change or service valves.
Damaged or worn push rod - Change push rod.
Cylinder block parts are worn out - Replace defective components as required.
Oil filter is blocked (if equipped) - Service or change oil filter.
| Excessive fuel consumption |
Throttle not fully open - Check throttle cable and adjust as required.
Carburetor main jet is improperly adjusted - Adjust it correctly.
Spark plug is loose or defective - Spark plug need to be replaced or tightened.
Burned, worn, or stuck valves - Replace or clean valves.
Worn rings, piston, or sleeve - Change faulty components.
Valve clearance is wrong - Need to adjust valve clearance.
| High oil consumption |
Seals or gaskets are wearing excessively - To repair leaks, replace worn parts.
Worn valve guides and valve stems - Replace defective valves.
Piston rings are seized or worn - Piston rings replacement required.
Scuffed cylinder liner or piston - Check liner and piston, install new components as required.
Breather pipe or hose is blocked - Replace or service.
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