Water in feul tank briggs and stratton scott bonner cylinder lawn mower

SOURCE: lawn mower

i dont understand the pulling the button - do you mean push the primer button - if you mean primer button it sounds like the high speed jet in the carb is dirty and needs service- you can attempt to start and once engine fires have someone continually push primer to keep running it ma clear the blockage - did You check the fuel tank for any water ?

SOURCE: Briggs & Stratton engine on Murray lawn mower

I always replace the air filter if its a paper element, and even if its a foam element I replace it rather than clean it. That said, engine stumbling is rarely and air flow problem - but it could be, so having a new filter assures no air restrictions.

I would drop the carbuerator bowl. On the bottom of the carb, near where the fuel line comes into the engine, should be a nut. Removing this nut allows the bowl to drop off the carb. Some engines the bowl screws off, you will have to look at the bowl. Often the bowl has sediment or sludge buildup inside. Cleaning the bottom of the bowl can prevent that sludge/sediment from plugging the intake tube. Even on newer mower models this is a common problem, the gas line tubing interior breaks down and the inside of the tubing can start degrading - ending up in the bowl as sludge.

After cleaning the bowl, I would add one ounce of fuel line cleaner to a full tank of fuel and run the entire tank of fuel. This will clean any deposits or "varnish" from the interior carb parts. Doing this and the first step will assure your carb is clean and functioning.

If that doesn't help, then I would look at the spacing between the magneto and coil assembly. If you want to do that I'd like you to write down all the model numbers and serial numbers on the engine nameplate, that way I can give you specific directions.

Hope this helps,
Gregg

SOURCE: Have a Briggs & Stratton lawn mower engine, 4.5

Is Blade new or causeing vibration .Chge blade,

Please rate Thank you jj505

SOURCE: My lawn mower briggs & stratton engine 650 series will not start

check the fly wheel and coil it may have rust on it if so sand it off

SOURCE: Briggs & Stratton Quattro lawn mower

computerscot is right. This engine is not designed to run slower than a few hundred RPM below maximum. The carb has a built-in fuel pump that only operates properly at relatively high speed. Your motor probably has either missing or weak throttle springs which will lower the RPM. Replace them and adjust the tension so that the speed is up. For a diagram of the carb and springs, check the Briggs & Stratton online user manual maintenence section. Look for file "briggsandstrattonMS5373-GB.pdf".