lawnmower motor

[motor_head]

i have an old snapper rear engine ridermower, one of the really small ones.
well it has a briggs and stratton 8hp engine on it and it runs like crap, if you engage the blade and start mowing it goes thud thud thud for like 10 seconds before it smooths out some i have adjusted the carb and cleaned it with sea foam and it still runs teribly

 

[BradenM]

So it's not responding to load?
Sounds like you might need a carb clean-maybe not enough fuel getting in when it's needed. Have you checked/replaced air filter?
Your sure it's not drivetrain?

 

[Kenny_McCormic]

Try new spark plug, points and condenser.

 

[motor_head]

its the engine not drive train air filter ok i might finally take a little time and actually take the carb apart and clean it i have only put seafoam in it and let it sit a few hours and when that didn't help at all i thought that it must not be that dirty

"Try new spark plug, points and condenser"
its a magneto

yes when you put much load on it it boggs down and after a few seconds revs up but not to 3600 rpm it sounds like it stays below that and it does hold a good rpm without load

 

[Kenny_McCormic]

New plug sill applies, bad plugs will do some WEIRD stuff.

 

[Kaptain Krunch]

Definitely a new plug, and carb cleaning. if that doesnt help then check compression. Is your carb set right? check your plug color.

 

[Tony]

maybe clean the exhaust ports.