Why does my engine start and then shut down?

Many engine performance problems can be linked to maintenance issues such as stale fuel, dirty air filter, fouled spark plug, and deteriorated oil.

A great way to help avoid these problems would be to perform an annual tune-up using a Briggs & Stratton Engine Care Kit.

If untreated fuel is more than a month old, this fuel will start to break down and engine stalling (in addition to fuel system component gumming) can result. That’s why it’s important to either drain the petrol from your outdoor power equipment before it sits idle during the winter, or add a fuel preservative/stabilizer to the fuel. 

For a typical example of how an engine may sound when it stalls due to lack of fuel flow, please listen to the following:

  • To prevent the fuel from going stale, purchase a Fresh Start Fuel Cartridge or a fuel stabilizer and mix the prescribed amount with your petrol.
  • Even better, keep a petrol can solely for your outdoor power equipment filled with petrol treated with our Fuel Treatment. That way, you will always have a supply of fresh, treated fuel used specifically for your outdoor power equipment.

If you’ve got stale petrol in your equipment, drain the petrol from the fuel tank completely and dispose of it properly, following your local municipalities’ regulations. NOTE: In most cases, this older fuel can be added to your car's fuel tank with no harmful effects.

Sometimes removing the old fuel and replacing with fresh, treated fuel may just solve the problem. If not, drain the old fuel and spray the inside of the fuel tank and carburettor with some carburettor cleaner. Finally, remove any sediment from the fuel tank and add fresh, treated petrol .

Another thing to consider is that certain equipment manufacturers place a plastic packing plug between the petrol cap and fuel tank. In order for there to be proper venting, ensure that this plug is removed.

If stale fuel is not at fault, next look at the ignition system. Did the engine suddenly stop after striking an object? If so, you likely sheared the flywheel key, which upsets the engine's ignition (spark) timing.

Your best source of information would be to consult your local Briggs & Stratton authorized dealer.

Your Briggs & Stratton authorized dealer has all the information relating to Briggs & Stratton warranty information, replacement engines, short blocks, parts, pricing, service/repair, specifications, etc.


Download the operator's manual for your Vanguard engine or equipment by following our step-by-step process.


Take advantage of the expertise your local dealer can provide for service and support on your Vanguard engine.

Please read and abide by any applicable Safety Information contained in your engine Operator's Manual. The material provided above is not intended to replace work performed by a Briggs & Stratton authorized dealerTerms and Conditions apply to all of the information presented on this website. Always be sure to completely read and understand your engine Operator's Manual.