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srivers15

Lawn mower won't restart without priming...

srivers15
12 years ago

Ok, so the mower had some running issue's that were fixed by pulling the carb & giving it a good cleaning. Put everything back together, give it a couple pushes on the bulb and it fires right up. After leaving running for about 5 minutes or so, I shut it off and go to re-start it and the only way it re-starts is if I push the primer bulb again(all other mowers I've had fire right up after being "warm"). Any suggestions on what could be wrong?

Comments (4)

  • baymee
    12 years ago

    There is possibly still some gunk in the main jet. Try any fuel system cleaner, such as Sea Foam, and use a few tanks of it.

    If that doesn't fix it, take a look at your main jet, which could be similar to one of these. You don't say what type of carb you have.

    {{gwi:126850}}

    {{gwi:126851}}

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    {{gwi:127778}}

  • srivers15
    Original Author
    12 years ago

    It's definitely got that type of jet that screws on through the fuel bowl. I cleaned it out with compressed air when I took it apart. I didn't check the float to see if it had gas in it though, could the float not being adjusted correctly cause this problem(if it can be adjusted)?

  • 1saxman
    12 years ago

    Cleaning out with air is not good enough - the small bleed MUST be manually rodded. Even carb spray is ineffective, but is okay to blow out any residue after rodding with the soft steel wire tie.
    Also, try this; Start the mower - use it to cut grass for at least five minutes, not just sitting. Turn it off for one minute (about the time it takes to empty a bag), then try to restart. If it starts under these conditions, you really don't need to do anything yet but you may in the future. Mowers today run very lean, and depending on the ambient temperature, can cool off enough in five minutes to need the choke to restart. Also, if the gas you're using is over thirty days old and was not stabilized when fresh, you should replace it with fresh stabilized fuel. I always buy mid-grade gas for my equipment because the volatiles in the fuel tend to vent everytime the can is opened. This way maybe I keep the fuel at minimum octane requirement as long as it lasts, which for me is almost all summer.
    Once you get the carb clean and the mower runs right, always use a fuel stabilizer/cleaner in your mower gas can, along with some Marvel Mystery Oil, 1 oz/gal to 2 oz/gal. You can add MMO to your 2-cycle can, up to 4 oz/gal in addition to the regular oil mix. All engines love this stuff.

  • andyma_gw
    12 years ago

    I use MMO and have had to do way less carb work as a result. I also use it to thin out and provide some gentle cleaning to the 20w50 oil I run in my old BMWs for winter