I have a Poulan 450 push lawnmower, and it's only a month old, and I've only used it once before to cut my yard. It worked perfectly, and now three weeks later I added gas to the mower, and the oil level is right where it needs to be, but it will sound like it's about to start and then hums back to a hault. Even after I prim it, it does the same thing over and over. I've tried 20 times, and it still will not start. Please help!

SOURCE: Won't stay running

these carb /air filter housing gaskets were notorious for warping? there are 2 screws behind the air cleaner remove those and disconnect the throttle cable pull the black square housing off and replace the gasket with a rubber one from local mower shop?

vince janis

• 718 Answers
• Posted on Sep 26, 2009

SOURCE: lawnmower wont start

Are you getting spark first of all. If you are getting spark do you have good gas? If you have good gas most likely your carb needs some attention maybe you had some old gas sitting in there and something inside is gummed up it might need cleaning.

SOURCE: Poulan 550 mower idle problme

Check air filter, replace if needed.
Check engine oil level and condition. Add/change as needed.
Check spark plug. Clean and re-gap if needed (.030 gap)
Drain the fuel and replace with fresh premium grade gasoline. If your local station has a notice on the pump regarding Ethanol content, drive to another station!

Most owner's manuals specify 89 octane or higher and most warranties become void if E85 fuel is used.

And finally, Oxygenated fuels are not your mower's best friend. :-)

Hope this helps.

SOURCE: poulan pro 6.5 21

Sounds like the center bowl nut is restricted. Remove it with either an 1/2 in or 9/16th box inch wrench and clean out all the holes with a small wire. Reinstall it and then give it a try. If that doesn't work then you'll have to remove the carburetor for a complete over haul. Take special note as to how the governor rod is connected before removing. If you have a digital camera take a picture of it, so you can refer to it in the event you can't remember how it goes back on. It probably doesn't have a fuel filter so it does become very subjected to dirt from the tank. The only filter you have there is manufactured in the tank outlet. some Tecumseh models just have a nipple and no filter built in them with a straight hose coming off the tank directly to the carburetor. Good luck

SOURCE: won't stay running

you may need to disassamble the carb and clean it thoroughly.