Lawn mower problem

I have a mower 6.0 HP Briggs Stratton engine. I let it sit over the winter with gas in the tank. I did however add fuel stabilzer. I fired it up for the first time this season and it is not running well. It runs fine for about 30 seconds then lowers the idle then back up then back down. Not a stable idle. I have changed the fuel and cleaned the plug and even cleaned the carb, although I did not take the carb apart I did clean it up inside and out with gumout carb cleaner.
My questions are should I replace the plug and/or carb? The carb is only 22 bucks, so I would rather not rebuild it.
What may have caused this? I added the fuel stabilzer to my genny, pressure washer and tiller, stored them with the gas in the tanks and have no problem with them, its just the mower.
Thanks for any help on this
Searcher
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
What kind of governer does the engine have? If it's flywheel fan type, kick the mice out of the housing.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Site Timeline

HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.