I have this old Snapper mower, it wont stay running for more than 2-3 minutes, starts to feel low on power, and then it sputters and died like it run ...

I have this old Snapper mower, it wont stay running for more than 2-3 minutes, starts to feel low on power, and then it sputters and died like it run out of fuel. Will not start up again unless rested for an hour.
After sitting for days, it starts fine on the first pull.
-New ignition coil
-New starter
-New fuel line and filter
-New spark plug
-Old battery
What is there to check next?

250 Piece Survival Gear First Aid Kit

LifeStraw Water Filter for Hiking and Preparedness

250 Piece Survival Gear First Aid Kit

  1. 10 months ago
    Anonymous

    Carburetor

    • 10 months ago
      Anonymous

      Make sure the vent valve atop the filler cap is working. (it needs to be open and free flowing, or the mower will do exactly what you described)
      Those sometimes have a little filter in the tank, as well as the inline filter. Check it for crud, and look for water.
      Then as mentioned, check the carb.

      • 10 months ago
        Anonymous

        This. Sounds like the filter is badly clogged or the vent is clogged. Motor sits for an hour and the carb bowl very slowly fills with fuel and will start, then dies because enough fuel isn't flowing from the tank to keep the bowl from emptying.

      • 10 months ago
        Anonymous

        Carb bowl is filling slow, as an0n stated.

        Tank filter should be suspected after what you've done already, again as stated/I concur. Give us the results.

        That filter is in the tank itself. Remove and empty tank. Use compressed air to gently blast backwards on the fuel outlet. Then, either use a little fuel or other appropriate solvent to slosh a few oz's in the tank, to lift up the debris, and dump the whole tank upside down.

        The main issue with ethanol fuels is they will more readily turn to gel/sludge than normal gasoline, and tend to clog those tank filters. Particularly in heat. Use STABIL MARINE, or similar. Will act to inhibit the bacteria that grows on ethanol and emits acid (correct me if I'm wrong anons). There are a few companies that make such a stabilizer, but I don't remember the names rn.

        Then, should be able to drop the bowl and clean that out. Even though you got it running, it won't hurt to take the carb bowl off and check it's condition. If you see metal flakes, clean it out. If you see signs of pitting, that's that ethanol fuel left in it. Always run your fuel stabilizer then drain your carb bowl, prior to putting it away before the end of season. Should have a little hex or screw to do that bowl removal, without pulling the carb.

        I've not worked on one of those models, but have seen either nearly the same or the identical model at a neighbors. They do run like a champ,

    • 9 months ago
      Anonymous

      This. Sometimes even the tiniest jet can be clogged, sometimes its so small it doesn't even look bad. Clean your carb thoroughly.

  2. 10 months ago
    Anonymous

    needle in carb is stuck

  3. 10 months ago
    Anonymous

    Put a new kit in the carby

  4. 10 months ago
    Anonymous

    Not a fuel problem I put good gas in it.

    • 10 months ago
      Anonymous

      It is a fuel problem if air can't get into the fuel tank to replace the fuel as it's used. As more and more fuel is pulled out of the tank it creates a stronger and stronger vacuum that eventually doesn't allow fuel to flow out any more. Which is why the mower runs for a few minutes then shuts off. Check your fuel tank vent.

      • 10 months ago
        Anonymous

        'i can't breaf' said the mower.

        • 9 months ago
          Anonymous

          >Mower
          Wow, hard R much? Your racism is showing my mowa

  5. 10 months ago
    Anonymous

    Anyone know what model of Snapper this is? I dont see any labels, and dont see an engine model.
    I'll buy a rebuilt kit for the car, venting the gas tank didnt help it run.

    • 10 months ago
      Anonymous

      Just open the carb up and check the needle and seat and float to make sure nothing is gummed up or clogged up...

    • 10 months ago
      Anonymous

      DID YOU remove the tank, OP?

      There's clearly a fuel supply clog.

      And no, 2-3 minutes is not a problem with the tank 'breathing'. Plus, that's not something that fails, typically. But gas turns to gel and along w any residue (chunky bits) will clog the little filter that's on the pickup inside the tank.

      • 10 months ago
        Anonymous

        low fuel flow on a snapper rear engine is caused by
        >you didn't put gas in it
        >you forgot to unscrew the vent on the gas cap moron
        >you have twigs and shit in the gas tank
        >water in the gasoline, wont gravity feed through some filters, but also just wouldn't run
        >gas tank outlet is obstructed
        >the fuel line is plugged, collapsed, kinked
        >the filter is plugged
        >the carb inlet is plugged
        >the carb vent is plugged (mud wasp)
        >the needle or seat is stuck or goo
        >the float is stuck or broke
        if you've made it this far the problem should be apparent
        if not, "please" do not bring it to a mechanic

        The tank is clean, and not clogged.
        new fuel line and filter.
        it flows fine.

        Valves are out of adjustment
        It dies after the engine gets to temp and the valves no longer seal

        i'll do a comp test after it gets hot to confirm if the carb isnt the issue.

        Did you take the carb apart? If it has spark, and has compression, then it’s fuel related and with that old thing I’d bet money it’s just the carb. Get a rebuild kit or a new carb if you’re real lazy prolly only $20

        i havnt looked at the carb yet, i'll get it to soon.
        found this video here: https://www.youtube.com/watch?v=IFSp3TBSZJg
        looks just like mine, and covers what I need to look at.
        thanks everyone, i'll post when I get it running.

        • 10 months ago
          Anonymous

          >i havnt looked at the carb yet, i'll get it to soon.
          What the hell are you waiting on? Get your ass off PrepHole and get your mower running anon!

        • 10 months ago
          Anonymous

          The first thing I do on any mystery sitting 'hasn't been run in x years' small gas engine, is a complete carb teardown and cleaning.

          That would have covered

          low fuel flow on a snapper rear engine is caused by
          >you didn't put gas in it
          >you forgot to unscrew the vent on the gas cap moron
          >you have twigs and shit in the gas tank
          >water in the gasoline, wont gravity feed through some filters, but also just wouldn't run
          >gas tank outlet is obstructed
          >the fuel line is plugged, collapsed, kinked
          >the filter is plugged
          >the carb inlet is plugged
          >the carb vent is plugged (mud wasp)
          >the needle or seat is stuck or goo
          >the float is stuck or broke
          if you've made it this far the problem should be apparent
          if not, "please" do not bring it to a mechanic

          particularly the last 4 points that anon made, already.

          If you get good flow from your tank and haven't even removed the carb & sprayed a little carb cleaner down the fuel jet, you should have, already.

  6. 10 months ago
    Anonymous

    Valves are out of adjustment
    It dies after the engine gets to temp and the valves no longer seal

    • 10 months ago
      Anonymous

      I would not discount this. I have fixed a few with that issue. Also clean any shit out of the cooling fins.

      Look up the section on compression:

      https://zippysha.re/Y0bcWa4dze/Briggs_1919_to_1981_AntiqueEngine_Manual_pdf

      It may be newer than this but for what its worth.

    • 10 months ago
      Anonymous

      Nice angle. Valves out of adjustment..

  7. 10 months ago
    Anonymous

    Fuel problem.

  8. 10 months ago
    Anonymous

    Did you take the carb apart? If it has spark, and has compression, then it’s fuel related and with that old thing I’d bet money it’s just the carb. Get a rebuild kit or a new carb if you’re real lazy prolly only $20

    • 10 months ago
      Anonymous

      A problem like this is slow fuel into the carb. Not the carb itself. Or that valve idea was interesting. A sticky float will cause the fuel inlet not to close = flooding, and noticeable extra amounts of gas pouring everywhere out of the carb, and contaminating the engine oil (usually). A float that doesn't open is unlikely, unleas the bowl's already been removed and reinstalled incorrectly.

      Maybe anon fixed it then ran himself over.

      We need pics, either way.

  9. 10 months ago
    Anonymous

    low fuel flow on a snapper rear engine is caused by
    >you didn't put gas in it
    >you forgot to unscrew the vent on the gas cap moron
    >you have twigs and shit in the gas tank
    >water in the gasoline, wont gravity feed through some filters, but also just wouldn't run
    >gas tank outlet is obstructed
    >the fuel line is plugged, collapsed, kinked
    >the filter is plugged
    >the carb inlet is plugged
    >the carb vent is plugged (mud wasp)
    >the needle or seat is stuck or goo
    >the float is stuck or broke
    if you've made it this far the problem should be apparent
    if not, "please" do not bring it to a mechanic

  10. 9 months ago
    Anonymous

    Hey. Ok here. This thing is on my parents land. I'm not out here often. I looked at the carb and it looks like it's been replaced.

    • 9 months ago
      Anonymous

      Never mind. I found the problem.

    • 9 months ago
      Anonymous

      >I looked at the carb and it looks like it's been replaced.
      They always look like that. Take it apart and clean it up with carb cleaner and paper towels. Make sure the jet(s) are unblocked. If your carb cleaner or gasoline warps the gaskets, let them dry and they'll probably return to shape. Wear gloves or suffer greatly. Don't breathe the fumes.
      If you still dont get spark, make sure that the magneto is gapped properly, the ignition coil wont work if it's more than a gnat's ass from the flywheel's magnet. Set it to (printer paper) away from the flywheel then bar it over and sure it doesn't crash into the flywheel before starting.
      If you have spark, the carbeurator works, and it still wont turn over, tweak the valves. Find online what the valve clearances are, then use feeler gauges or printer paper (times N) to set the gaps

      Also don't just replace shit willy-nilly dude, you're eating into the value of an already worthless PoS mower. these things age like white women and basically return to iron ore by the time they're 10

      • 9 months ago
        Anonymous

        my tarded self assumed you had no-start, oh well. still applies

  11. 9 months ago
    Anonymous

    What's this thing? A check valve? Shouldn't that be a filter.
    This can't be right. it looks new. Must have been replaced by the seller

    • 9 months ago
      Anonymous

      It's an inline fuel fliter, I'm a minibiker.

Your email address will not be published. Required fields are marked *