Toro Lawn Mower Engine Surging

My 2019 toro ss3225 with the toro built single cylinder engine.

Toro lawn mower engine surging.

Starting surging when it idles. Check and clean the vent. The warmer the engine is the worse it gets. Although it may mow your lawn competently the whole time you ll probably be thinking why does my lawn mower sound like it is surging it won t be such an enjoyable mowing session will it.

Dirty faulty carburetor. Runs rough so could it use a tune up. I can manually put the choke on with my finger and it will smooth right out. At the start of a new season they either add fresh gas to the old gas or try to start the mower engine using the old gas.

It now has 159 2 hrs. Tjcox6841 tom you did not state your engine or model so i will post some what generic answer. A mower left in a heavy rain or condensation on a hot summer day can choke the engine. Starting doing this when i had about 100 hours on the meter this past july.

The owners manual said to replace the air filter and spark plug at 100 hours. Sometimes ethanol in gasoline can cause damage to the carb and it creates surging. Empty the gas tank properly. The number one cause of mower engine surge is using gasoline that is old or contaminated perhaps by water condensation usually as a result of leaving gas in the mower over the winter.

Lawn mower surging results from continual accelerating and decelerating of engine revolutions. This toro lawnmower with a briggs and stratton engine starts and runs but only at half speed. Surging is also caused by water that got into the fuel. If you do all that and it s still surging i would replace the carburetor with the proper oem replacement carb.

The most common reason for a surging lawn mower engine is a blockage in the fuel supply but there are other possibilities. However if it keeps surging while you re using it like going up and down or even dies then you have every reason to be concerned. Make sure the fuel is flowing easily through the fuel lines. Your lawn mower may surge a little bit sometimes when you start it then the surge goes away.

There s nothing to worry about that. Five problems that cause lawn mower surging. Replace the fuel in the tank and the fuel filter. So what causes lawn mower engine surging.

Many homeowners forget or choose not to drain the gas from their mower s tank at the end of each season. Sounds like the governor linkage may be stuck broken linkage spring. Toro lawn mower. The mower may not die completely as this happens but it may surge the entire time you mow the lawn.