I'm no kind of small engine mechanic but my friend gave me a gas mower which worked great when I started it. Turned it off and back on a few times, then when I was almost finished the yard it conked out in some thick weeds and wouldn't start again.

Funny thing is if I turn it on its side, and then set it back up again, it will start up and sputter for two or three seconds before dying. And then nothing, no matter how many times I pull the cord. But turn it over sideways, set it back upright, and I can get it going for a few seconds.

Any ideas?

  • 2
    There is petrol in it right?
    – user5079
    Commented Aug 18, 2019 at 18:27
  • No "petrol", but plenty of gasoline actually. Commented Aug 18, 2019 at 22:58
  • Dirty fuel tank ?
    – mike65535
    Commented Aug 20, 2019 at 13:40
  • @MartyGreen we tolerate the use of words like "petrol" & "gasoline" and accept them as correct in either case, otherwise some of us would be replacing "tire" with "tyre" (or vice versa) "bonnet" with "hood" etc etc
    – Solar Mike
    Commented Aug 21, 2019 at 5:56
  • Can't take a little joke? Commented Aug 21, 2019 at 14:19

1 Answer 1


Two possible answers here.

1) Your system has a high mounted tank and fuel is gravity fed to a fuel bowl at bottom of carburetor. Its possible old fuel clogged a main jet and your tip over test bypassed the blockage with enough fuel to run for a few minutes. Note a common fault is blockage at fuel bowl inlet jet.

2) Your system includes a membrane design fuel pump and its not able to suck fuel up from the gas tank. In this system the fuel tank is mounted below the carburetor. This could be a torn pump membrane or a clogged fuel inlet at the pickup tube inside the tank.

Both defects occur by long term storage of old fuel in the tank. Old fuel gums up stuff... they say the fuel turns to varnish. Corrective action is to find the blockage and clear it.

  • Absolutely right. My friend came over yesterday and pulled the engine apart. The little port into the venturi was plugged, and he blew it out (that's what you called the fuel bowl inlet jet?). Put the engine back together and it worked. Commented Aug 22, 2019 at 18:58

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