What's wrong with my lanmower?

I fired up the lawnmower today to get the lawns trimmed before the rain hits later tonight. It’s the second time I’ve had the lawnmower out and about since last fall. The first time, about 3 weeks ago, went well. Today the back lawn went well. When I moved the lawnmower around to the front lawn and fired it up, it went

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non-stop. I checked the air filter (fine), gas (fine), and started it again. It ran fine for about 30 seconds, then started into the up-down cycle again. It worked and allowed me to get the lawn mowed, but I’m wondering what this means? Is my mower dying, or is this easily repairable?

Craftsman Model 917 4.5 hp gas mower, about 5 years old.

Is it wireless or cabled? A lanmower will choke up on the cables if you try to trim a cabled lan.

I do not understand what you mean by this.

Ethernet cables are 8 24 gauge wires and a bunch of insulation. You run a lanmower over those, they’ll get all tangled up in the blades and stop the engine.

I’d say it’s a restriction in the gas flow somewhere or water. Clean out the fuel lines and drain the gas tank. It could be other things but that would be my first check. Drain the fuel bowl too.

Could it be gas quality at all, since it’s been sitting a while?

It could be debris or water in the gas. Water rolls around on the bottom of the tank and gets sucked in small globules at a time. I’ve seen it happen so you get the cycling speeds. Pure gas full speed. Water arrives and it slows down. Gas arrives and you go full speed again. It can be your gas can has water in the bottom and you filled the working mover with water contaminated gas.

Does it have a choke? Did you leave the choke on somehow, or inadvertently knock it into choke position when you moved it to your back yard?

Change the air filter. I always do that. Then I take it to the repair shop.

Correct. I work in IT and lanmowers are pretty useless when in a wet area. It shreds plastic and wire all over the place and will destroy the engine. They are dangerous to have around too because some janitor is going to decide to have some late night fun and cause millions of dollars worth of damage in the blink of an eye. I usually just get a bunch of high school kids cut it with scissors for all the trouble it takes to bring a large company to its knees.

If the lanmower is just having standard engine trouble, the testing and fix is the same as the equipment you find in other applications like go-karts and landscaping. Drain the gas, check for obstructions in the deck, clean the air filter, and then check the spark plug for fouling if you need to. It is most like the gas or the air filter which anyone can do themselves if you look at the manual. I have had good luck just by burning off some bad gas and adding more as you use it but you can just flip it over to drain it quickly. Don’t use your lanmower anywhere other than your own home though. There could be serious charges in some jurisdictions. I don’t even know why Home Depot sells them.

It has a little rubber button you press 3 times, then pull the starter cord. I can check if it’s stuck, along with the other suggestions.

I worked where they made the parts for those small engine primers. They don’t get stuck. You could break the plastic gas line connector off or tear the material, but that would be obvious and not stuck.

That simplifies the task list. Thanks.

It sounds like there is water in the gas. Remove the carburetor float bowl and drain the tank into a glass container. It will probably look like there is a puddle of something at the bottom of the gas–that is water. Better yet, just replace the gas. Even better yet, use sheep to cut your lan–they take longer but trim it evenly so that everyone has a comparable connection speed no matter where they work in the building.

Try disabling and re-enabling the Dual Hose Carburetor Pulse (DHCP), and if that doesn’t work, try disabling the Neutral Alignment Transmission (NAT), those are the usual culprits when lanmowers go bad.

Or you could try putting your lanmower into De-Mulch Zoning (DMZ), although that’s a little risky. Don’t operate in DMZ mode for too long.

I don’t recommend it. They drop packets all over the place.

I had a lawnmower that did exactly the same thing and corrected it by adjusting the ‘lean/rich’ screw at the carburetor. See your manual to locate and adjust it.

Another potential cause is a gummed up carb that can be cleaned with most carburetor cleaner sprays.

The only problem is that sheep mow up the lanscaping.

I once hired Mowery’s sheep to do this for me, but she had a little LAN, little LAN, little LAN, whose IP lease was white as I/O, and everywhere Mowery went, the LAN was sure to go.

It followed her to spool one day, spool one day, spool one day, and made the children Plug and Play, Plug and Play, Plug and Play, to see LAN at the spool that day.

And that’s the story of LAN and Mowery.

Since it was fine for a number of mowings this year and suddenly developed this problem I suggest he not touch the carburetor mixture screw.

Agree. Water in the carb/gas would be my number one thought, so drain it completely, and try fresh gas. Particularly if you last fueled it up with a gas containing ethanol, as it holds on to water like a sponge.

The second most likely on my list would be bad o-rings in the carb / fuel system, or even pinhole leaks in the hose delivering the gas to the carb, allowing air into the fuel.

The third most likely, though way down the list with current gasoline formations would be fouling from having the gas turn to ‘varnish’, which will definitely clog up the fuel system. Modern gasoline though is very good at remaining stable for 6 months to a year with virtually no degradation except color.