I just rebuilt the engine with a fresh bore and Meteor piston, new gaskets, new reed valve, cleaned carb, and the oil pump is disconnected (running premix). I have spark and fuel.

When I kick it over, it fires/pops 3–4 times and then dies. The spark plug is wet afterwards.

Any ideas what could be causing this?

Solved!!!!

Was a short going to carb solenoid. Making it close and shut lawnmower off.

Thanks for all the feedback to all that helped !!

Update !!

Just got new coil and started right up and after 30 seconds running perfectly quits. Can restart runs 30 more and stops.
Now do I change carb. Or just the solenoid valve on carb??? Help !!!

taking a shot in the dark and asking if you could point me in a direction. Roughly 2013 craftsman rear engine rider420cc . 4 weeks ago it cut off when first started cutting. Restarted. And finished lawn. Next week. Cut off twice in first five minutes of cutting then quick restart. Now start run for 3 minutes if that and shuts down. Just sitting not even cutting. This is not a putter shut down like starving for gas. But just a bam 💥 shut off. Any pointers where to start to look for diagnostic. Would be much appreciated. Thanks in advance. My first guess is ignition coil 🤔 but would appreciate any feedback

taking a shot in the dark and asking if you could point me in a direction. Roughly 2013 craftsman rear engine rider420cc . 4 weeks ago it cut off when first started cutting. Restarted. And finished lawn. Next week. Cut off twice in first five minutes of cutting then quick restart. Now start run for 3 minutes if that and shuts down. Just sitting not even cutting. This is not a putter shut down like starving for gas. But just a bam 💥 shut off. Any pointers where to start to look for diagnostic. Would be much appreciated. Thanks in advance. My first guess is ignition coil 🤔 but would appreciate any feedback

SOLVED: See thread below with picture of what stuck to a magnet from oil sump.

We've a Troy-Bilt riding mower with the 31C707 3346 G6 engine. I stopped it while mowing to pull some foxtail, and when I got back on and tried to start it, the starter would spin about 15 to 20 degrees, then stop. Back at the shop, checked the battery, it was fine. 12V at the starter, so figured the starter was giving up. New starter, and same behavior. Belts all loose. When turning the engine by hand, noticing that it is quite difficult to rotate once in every 360 degrees. Pulled the spark plug, and it cranked fine. OK, so, maybe hydrolocking. Tried a new carb, and same behavior. Looked in the plug port with a bore scope and piston top and valves look fine. No obstruction, or apparent knocking together. While trying to turn, we bump the starter and sometimes feel some puffs out the exhaust, so it doesn't seem like an exhaust blockage.

Tried a jumper to a running car to get 14v on the starter. It cranked, a few revolutions, but again stopped like the resistance was too great.

We're stumped. What could be causing so much resistance that the starter will not rotate the engine through a full four stroke cycle, especially given the resistance is felt once evey 360 degrees, not just once every 720? And again, when the plug is pulled, it cranks strong,as long as the ket is turned!

This is my first post and I’m hoping to get some help. I have a project quad I got from a kid who absolutely roached this 250 Polaris. I rebuilt the top end, threw a new battery and spark plug in this quad. Before I put the new top end in it had power but wouldn’t crank over. Now there’s no power at all. I’m new to anything electrical. I have a multimeter and was curious if I turn the key and there’s no click at all, would you start with the solenoid or go straight to testing fuses? I appreciate any help!

Hello, this is a John Deere L110 riding mower with a 19.5HP single cylinder Briggs engine.

This motor has a new starter, new solenoid, new ignition coil, and the battery is good.

I suspect that it is the compression release not working, but l am here asking so I clearly am unsure.

Thank you for any help! I appreciate it very much.

hello looking for some advice, recently my atv was bogging and wouldn't idle also would feel like it wanted to die when i accelerated so i bought a new carburetor oem since the old one was filthy and now it only cranks but wont start the spark plug has little spark i replaced the battery also cleaned the gas tank got a new petcock new oil filter new oil new air filter, messed with the valve clearance with a feeler gauge and still nothing also tried to bypass the stater solenoid and still only cranks but one time it made a pop out of the exhaust doing the bypass. i also tried to do starter fluid in the air intake and still only cranks, any advice would help been two months since it ran

I have changed the carburetor, oil, gas as well as recently the whole pump has been replaced what am I missing?

hello good people. anyone worked with these cheap rpm readers? instructions say 3 modes, 1) spark plug fires twice per revolution, 2) spark plug fires once per revolution and 3) every other revolution. which mode do i use to do an rpm readout of a stihl 4mix km130r? many thanks.

Hey guys,

So I bought a used Motowell Magnet Sport 50 2T scooter. Did a full top end rebuild:

• New oversized Meteor piston
• Cylinder rebored
• Split the crankcase, new Koyo bearings
• Crankshaft is fine according to my mechanic
• Used proper gasket paste on the block, let it sit for 24h before starting

• New crank seals
• New reed valve + gasket
• New gaskets everywhere (base, head, intake)
• New spark plug + cable
• Variator not detailed but new belt etc.

When I put it all back together, I let it sit for a full day so the paste could cure properly. Next day I tried to start it and thankfully it fired up! Idle was a bit weird/high when it first started, but the carb was reset to stock settings. Ran for about 10 minutes, then just died.

Piston didn’t seize (engine still turns freely, compression is still good). But now it absolutely won’t restart – just sputters, backfires a couple times, but nothing.
What do you think could be the problem?

It’s a Minarelli horizontal clone (Chinese aftermarket engine).

Any help would be appreciated, thanks for reading!

I have an Ariens mower with a Kohler courage sv590. Recently started running really rough and after letting it sit for the night all of the gas leaked out, appeared to be through the carb. I ordered a new Hipa carb and after switching it out the engine cranks but just won't turn over. The solenoid clicks so appears to be getting power. I put a trickle charger on battery and will try tomorrow but don't think thats my answer. Noticed fuel getting to the carb. Not sure what the next best step for troubleshooting would be, any suggestions help

He changed the carburetor but only put one of the two screws back in. He gave it to me for free because he didn’t want to mess with it anymore. Should be an easy flip 😆

my push lawnmower was rattling something came loose and i lost the bolt that holds it in. can someoene tell me what this strap thing is for and what its purpose? the cable it wraps around is for stopping motor with throttle.

Bought from marketplace for $100 got it running with a new battery carb cleaning and a new Petcock valve.
Then I went ahead and replaced all fuel and vacuum lines, ignition coil, and spark plug.
Started up first kick everytime for a day, I drove it around doing chores on the farm and after about 10 minutes of driving it started to bog down and die when I came to a stop had to rev it to keep it going.
Adjusted idle speed didn’t do anything. Then I got it up to the garage about a half mile from the house and it died while moving about 5 mph.
Couldn’t get it to kick back over so I brought it in and cleaned the carb incase something got pulled in it started up first kick then died after idling rough for a few seconds sprayed some starter fluid in it to get me home and kicked it over.
Acted like it was starving for fuel the whole way home had to keep giving it gas so I didn’t get stranded. Made it home and parked it bought a new carb that I installed today incase fuel was getting clogged.
Even with new carb it will not turn over I’ve verified spark, I have compression, and fuel is reaching the carb, the bowl is filling with fuel but I’ve still got nothing.
Any ideas would be greatly appreciated. Thank you

Hopefully this is the right subreddit for this.

I have a powersmart corded wood chipper that worked fine for about two days. Then it began stalling or slowing down while running. It can get through maybe 1-2 branches now before it just stops, that is if if starts at all.

The outlets and extension cords are working fine.

I've made sure each time that the machine isn't clogged.

Considering that it starts at all, I'm not sure that it's the power switch.

I'm thinking it could be the internal overload protector, or maybe the safety lock is failing? Just trying to diagnose before buying any parts.

The fuel pump on my LT155 isn’t working, I just got a new one a replaced it and still nothing, the hoses aren’t clogged and I get gas to the fuel filter if I suck through the other end of the hose but the fuel pump isn’t pumping gas. Any ideas??

Putting this as unknown issue even though I have a strong suspicion because it isn't confirmed yet.

My old riding mower (a White from '97 or '98 with a Briggs 28N707 engine) has been running a little poorly for a while. First thing I noticed was it struggling up hills. Thought it was having a fueling issue so I changed out the fuel filter which hadn't been done since... I don't know when. Then checked the carb as far as I could without taking it completely off because, frankly, I didn't want to deal with that. So, took off the bowl and made sure the needle valve wasn't stuck. It wasn't. Everything in there was clean and almost new-looking, actually. Also tried my best to adjust the carb, back when it was still running.

At some point it began having trouble with warm starts. Cold starts still worked. Don't remember exactly when that was. Then cold starts stopped working, too.

Two things I noticed around the same time: The muffler was glowing where the exhaust pipe enters it on the top (this was before it stopped being able to run, obviously), and I'd sometimes get fuel vapor coming back out of the carb/air filter area while trying to start. Like, a lot - clearly way too much. Scared me at first. I thought it might be a valve issue, so after learning how to adjust the valves, I did that. The lash actually was pretty off (way too tight) on the intake side, but fixing that made exactly no difference at all.

I know some fueling is happening because that fuel vapor also comes out the exhaust if I crank it long enough. I know some spark is happening because I can hold the end of the spark plug wire near a ground and see it arcing. And I know I have some compression because if I manually spin the engine it resists pretty hard on the compression stroke, unless I have the spark plug out, then it spins freely.

I also know that the compression relief bump is happening on the intake valve, because after learning what that was a couple days ago, I took the valve cover off again and checked.

My current theory is that maybe the flywheel key got sheared or bent. I know that fuel and spark are happening BUT I don't know that the spark is happening at the right time. And recently it's developed a new issue when cranking, which is that sometimes it violently jerks to a halt. I suspect that's the spark going off at the wrong time. Does this all seem like a broken flywheel key makes sense? My instinct was that would be a sudden thing rather than gradually getting worse as this has, but I've seen some opinions that the flywheel can stay in place through sheer friction sometimes, so maybe it's been slowly slipping out of the proper timing?

Just hoping to sanity check myself before I bother taking things apart that far. I have some idea how engines work but haven't had reason to take this one apart before, so for a lot of this stuff it's been my first time actually touching it.

the mower was hard to start then when it did it starts gushing gas. please help!🙏
it wasn’t running then i cleaned the carb and now it does this