Lawnmower Will Not Start - You Will Never Guess Why!

Lawnmower Will Not Start - You Will Never Guess Why
Is your lawnmower hard to start or does it kickback when you try to start it? If so you may have a sheared flywheel key.
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Easy to follow and thorough step by step tutorials do it yourself (DIY) to help you with your broken lawn and garden equipment including snowblowers.
I do my best to teach you how to easily diagnose small engine problems the fastest, quickest and most efficient way with real repairs beyond just replacing a spark plug. These tips are for both the homeowner and shop owner.
Whether it be a handheld, two stroke, two cycle engine like a chainsaw, weed eater, weed wacker, string trimmer, grass trimmer, line trimmer, hedge trimmer, strimmer, brush cutter, leaf blower, or four stroke, four cycle units like a lawnmower, wood splitter, lawn tractor, snowblower, pressure washer, generator or a ride on mower that needs parts installed or replaced, I’m your go-to guy.
My favorite brands of spark plugs are NGK and Champion and are the ones I recommend.
I’ve been a small engine mechanic for many decades and also run my own repair shop so my videos are loaded with tips and tricks that I have learned and want to share with you. You will also find many tool and product reviews from top brands on my channel as well.
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Due to factors beyond the control of DONYBOY73 “The Small Engine Doctor”, it cannot guarantee against unauthorized modifications of this information, or improper use of this information. DONYBOY73 “The Small Engine Doctor” assumes no liability for property damage or injury incurred as a result of any of the information contained in this video. DONYBOY73 “The Small Engine Doctor” recommends safe practices when working with power tools, hand tools, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this video. Due to factors beyond the control of DONYBOY73 “The Small Engine Doctor”, no information contained in this video shall create any express or implied warranty or guarantee of any particular result. Any injury, damage or loss that may result from improper use of these tools, equipment, or the information contained in this video is the sole responsibility of the user and not DONYBOY73 “The Small Engine Doctor".
#donyboy73 #briggsandstratton #lawnmower

[@jamespython5147]

Nice to see a video that is straight to the subject, not like a whole life story, explaining everything in their garage and a pat of a dog like most of them.

[@devinmccloud]

Great Channel. You understand youtube. No fat or fluff. No drawn out nonsense and unneeded content.

[@ehrmanf]

You saved my Lawnmower. Just disassembled it and the key ist broken. This will be a fast and easy repair. Many thanks from me!

[@dwaynemadsen964]

Sometimes I have self-doubts and your videos often fix that issue! I have the leaf blower equivalent of this issue, I think. Customer was using the blower; clothing was sucked into the machine, and it died and will not start. Has spark, has compression, has gas, etc. I wanted another opinion before I tear into this box store model because it is a pain to work on. Last year he snapped the starter rope, and the entire machine has to be disassembled to get to it. Thank you for sharing and stay safe.

[@simonrisdon1901]

Hi, thank you Don for this video. I'm a heavy equipment mechanic, I have notice my lawn mower have a problem but now that I saw you video, I'm pretty sure I found what it is. Another symptom I noticed it s if you take off your air filter and you crank, there is a atomized shot of gas coming out.

[@johnnellis3025]

I have to hurry, i hope my mower is still out at the curb.

[@_MOORE_1986]

Lol

[@dennismiller8602]

Lol

[@philliphall5198]

lol 😂

[@MozoTyce1]

Brilliant ! You described the symptoms perfectly. My Wilko DG400 was doing exactly as you described, i checked and found the woodruff key sheared. Replaced it and started second 'easy' pull - thank you for posting this.

[@1danleung]

Wow, my mower has all three symptoms and run like hell. I'm going to replace the key. Now I realize its such a critical part for timely firing. Thank you for sharing.

[@GoogleAccount-ii9sj]

Did it work?

[@1danleung]

@@GoogleAccount-ii9sj works! the old key was bended. after replace, it starts easy and run smooth.

[@RickBolt]

Thank you. I have been troubleshooting my mower for days and this helped me find the solution.

[@Ecksterphono]

By the way on some lawn flywheels it has instructions embossed right on the flywheel " never use steel key" or some wording like that (and even use flywheel puller). Always use an aluminum key on lawnmower flywheels or certain engines that recommend it. If in doubt check repair manual. Thing is an aluminum key cam prevent crankshaft damage or breakage in the event of the lawnmower blade wacking against a fixed object or big branch by just shearing the key. Some engines even have offset keys for ignition timing.

[@jerryshapiro3402]

Thanks for explaining the symptoms of a sheared flywheel key. I ran over part of the concrete curb. The mower still worked.. But the next time I tried to start it the engine made a loud backfire noise .

[@markmays5041]

Thanks for your videos. I always learn from them. I've fixed my chainsaw, weedeater and lawnmower all, with your help.

[@geneballay9590]

Very good. Three years ago my wife hit a large rock, and my lawnmower began to behave just as in your example. I just put it away and bought a new one. Now I am gonna get it ut check that shear pin

[@Bigshoots86]

Well?

[@Zinkevm1]

What happened when you had it checked out? Was it sheared?

[@stephenc4161]

Will never no lol..

[@jjjohn5914]

Thanks...ur the only one that mentioned the oil from the vent tube...I was wondering where it came from. Mine ran and sheared the tabs for the mower blade in use...then the mower after stopping could not restart due to full shear of pin.

[@aleblanc3547]

Nice reminder to check for this problem before you just toss the machine. Thanks, Dony.

[@242176]

My career is over.. people will no longer put their mowers curbside for me to pick up for scrap! Seriously though, great video, and thanks for all the info👍👍

[@ct7625]

Neighbor brought me his lawnmower that won't start. Blade is very loose. Told me he hit a steel pipe and mower stopped. Tomorrow's project. Great you tube channel

[@dbmeyers7416]

Excellent video and instruction donyboy! Really concise. My engine flywheel key was perfect, so I am back to the drawing board, as they say. When pulling starter cord, I still have symptoms you pointed out. I am totally puzzled now? Wonder if timing marks on cam and crank are incorrect. Connecting rod was replaced on this engine years ago. With spark plug out, engine spins easily.

[@semco72057]

I thank you for showing up these symptoms of a bad flywheel key. Take care and I hope you have a great week.

[@tomcappel7441]

You are always so good at providing detail and extra information so we understand. I never thought about a broken handle as being a signal that there may be a broken fly wheel key. Most appreciated! Great video!

[@TheLawnmowerLady]

Backfiring is a common symptom of bad timing in old two-stroke scooters. I had an electric start mower my shop in a few weeks ago. Charged the battery, it turned over OK but slowly, and backfired about every 5-6 turns of engine. Pulled on the cord, and sure enough, it yanked right out of my hand. Key was nicely sheared in two.

[@firebrand07]

Thank you! My Briggs Intek 7hp flywheel key is partially sheered, it looks like an offset key. All of those symptoms apply. The rope snapped out of my right hand, hit my left hand and nearly broke it, instant golf ball purple bruise. Anyways, now waiting on keys to be shipped.

[@stoolie10]

You are my go to small engine information man.i think I have this symptom currently on my briggs and stratton mower. Hope your having a great day.

[@randolphpatterson5061]

I've got a Briggs 3.5 hp motor with a sheared key, and when trying to start it the plug fires when the intake valve is wide open and a "pop" comes out of the carb. It stands to reason that the magnet triggering the pulse into the coil isn't where it should be, due to the flywheel having rotated away from its proper position. Easy fix.

[@peterford9369]

Good video. Timing is a major factor in engine performance and not many utubers will even mention it, guessing cause of the rarity of the happening. But you are right,,, hitting a sidewalk or root or obstacle that dead stops your mower especially,, can cause the key to partially or completely shear. Good information to look for and usually easy. thanks Don.

[@mowwow1998]

had a briggs stratton 450 148cc that had surging issues and also making occasional popping sounds while running. Tried all the usual solutions like cleaning and rebuilding the carb, even replaced governor springs, tried to adjust running speed by bending the tabs on the kill switch bracket, checkd for airleaks etc etc, nothing I did worked, eventualy decided to pull the engine apart and rebuild, when I took the flywheel off I noticed the keyway was slightly sheared and this ended up being the issue causing all my problems.

[@grantw.whitwam9948]

I had that exact thing happen on my 7hp mower with a Briggs. Hit a piece of rusty pipe, sheared it all the way and wouldn't start at all. I managed to figure it out my self and fix it. I also noticed on my 7hp, you really have to tighten the blade bolt a lot more than on all other mowers I have.

[@ExmarkDude]

Backfiring is another symptom of a sheared key, usually happens when it kicks back while trying to start it.

[@MissouriOldTimer]

on the old Tecumseh engines they used a steel key and an aluminum flywheel and many times when the blade hit something solid the flywheel would crack right at the key way.

[@jamesmullins3219]

backfires also can occur with a partially sheared key. Loud and scary when backfires make flames come our of muffler. good diagnostic video.. Another video on replacing key would be good.

[@jesseguerra8642]

Thanks for sharing this info. I will try to repair my (1.5 season old) PowerSmart self propelled mower.

[@ClassicTV4U]

I hope this is the issue on my Briggs & Stratton 4.0; a couple of summers ago, I ran over a small group of thin tree branches (less than 8 inches in length)--the engine started making a slight ticking noise and small spots of oil began to appear on the deck. After I shut it down, I tried to restart it, only to be greeted by the ol' starter rope snap back! Thankfully I have a spare mower, but as soon as I can find the correct flywheel key, I will attempt this.

[@alexanderchuyko4889]

Yes, I recognized this issue. Exactly what we have right now in a Briggs 7.25 HP engine of our lawn mower. It seems like ignition points are wrong. However, some people advised that it`s most likely a camshaft problem. It`s made of plastic and pretty common issue when its plastic gear wheel is getting loose on its metal axle, or a decompression mechanism is damaged. Do you have an idea how to diagnose it correctly before engine disassembly, please? Thank you

[@arciefan]

Maybe not a symptom, on the running of the engine, but definitely check the blade for damage and balance. And obviously oil level which I know you would do both. Great video !

[@billjensen6216]

This may seem like a situation for a bad key on the flywheel. But I was working in a riding mower, and it had all these symptoms. However, the key was good and straight. The problem turned out to be bad wire connections. I cleaned up the grounds, and the power wire ends on the whole machine, including start solenoid. Now the thing starts great and runs fantastic. I say this as I now have another riding mower sitting in my shop with the extra same issue. Hard crank hard start. Kick back against the starter, and occasionally, it will back fire just like the other engine on the other riding mower. OHV engines both are briggs and Stratton 17.5 hp engines. The only difference between the symptoms of a bad flywheel key and bad ground and power wire ends is that the mower when started runs great if it's a power or ground issue. And a bad key in has issues while running both may not start. So start with the key on the shaft and flywheel first. And eliminate that possibility first. Electrical wire cleaning is a long pain in the ass. As you have to clean every end positive and ground from the battery to the starter and the flywheel and coil pack and reset the coil pack to spec distance from the flywheel. A basic business card works for this.

[@curtite]

Thank you so much for the symptoms. After removal to check the kill switch underneath the flywheel. I believe that I incorrectly misaligned flywheel and key while reassembling.

[@rich3500]

On older engines with points, if the points are driven by a flat or a cam on the crankshaft the ignition timing would not change, however the spark will be weaker or there might be no spark because the magnets in the flywheel do not pass the magneto coil at the right time. So if the flywheel key has only sheared a small amount there could be no symptoms.

[@edwardrolling]

Thanks, that is exactly what is wrong with my mower. I should be able to fix that myself.Thanks again!

[@hoss1947]

I have a John Deere riding lawn mower model 125, it is powered by a Brigs and Stratton single cylinder engine . I bought it in 2009, it gave great service until this summer. It stopped running, and I found that the flywheel key was sheared. I put a new key in it and it started up, but only ran for about 3 seconds, and sheared that key. After the third sheared key I figured that it was an internal problem. After talking to some people I was told that some of those engines had a camshaft that had a nylon gear that is pressed onto the camshaft. Have you run across this problem? I plan on opening the engine case and see if this is the problem. Let me know your thoughts on this. Thanks for all of the info you pass on to us.

[@martystevens3969]

To remove a flywheel, put a block of wood on the top of the crank. Use a pry bar to pull up on the flywheel. Now, hit the wood with a hammer and watch the flywheel come off!

[@princessmimi6776]

That worked for me thanks!

[@lzh3131]

I read your comment from 6yrs. ago on “donyboy73”, removing the flywheel to replace sheared pin. I watched a lot of other videos, some you need special tools, other very unorthodox methods. Your method seemed the most logical, and addressed the not cracking the fly wheel. You answered my question. Thank you very much for commenting. 👍👍👍

[@Candoit2]

Thanks! Great instructional video!!

[@ronarndt6722]

Thanks. Great quick video and if confirms suspicions I have had and will check FW keys and timing(s).

[@maedrosbott5274]

This helped me to fix a problem with my car, thanks a lot.

[@vanalstyne9834]

I bet this is easily missed, thanks for the heads up.

[@motoman5023]

They also run like they have a slight ignition miss you can,t get to go away almost like a poping sound

[@marcsangiuliano4273]

Definitely the best info on flywheel! Mine is doing some of your symptoms but mostly smoking (exhaust) from underneath, where the blade is, on the front left where the self propelled cover is. It's a Toro recycler. Any help would be awesome.

[@doublewide6]

Nice video Donny. Only symptom I can think of that I did not hear was the burning red muffler when the key is partially sheared because the ignition is forward causing a hot run condition.

[@donyboy73]

yes good one!

[@geyser3445]

Was mowing with my Honda mower and went over a real thick patch of grass and the mower almost stopped and wouldn't make enough power (and smoked a little bit). Thought it was the flywheel key. Took off the cover and before I went to check the flywheel key, noticed one side of the armature/magneto/coil was touching the flywheel. Flywheel was very scraped up I readjusted the armature and the mower started right up and ran fine. Still not sure if the thick grass I tried to mow could cause this problem.

[@thesmallengineguy4694]

Thank you sir!! Awesome video and very informative!!

[@ChikinTown]

Have you ever heard of or yourself sheared a flywheel key by using an impact gun to remove an engine pulley? yesterday I was really hammering with an impact gun on a stubborn bolt holding a pulley on. Never got it loose. But I wonder if all that impact skewed the flywheel just enough to make my engine run rough. Going to pull it apart today and see. If you think about it it's sort of impacting the crank like hitting a rock or a stump would and all the impact repeatedly might misaligned the fly wheel? On a 15 HP Briggs.

[@laurencereid1947]

My ride on wont start all I did was take fly wheel off and put back on I 180 dgs out of timing now key looks ok

[@johnwfleming2077]

Craftsman power washer - No resistance/compression to rope pull. Is that a completely sheared flywheel key? Flywheel cup IS being engaged.

[@thurm101]

This is exactly what is going on with my rider. I hit a rock last week and now my mower is weak. Now how do I replace this on my Briggs & Stratton vtwin.

[@Kuwaitin08]

Love the videos! Quick question... I was given a Yazoo 26" Self Propelled mower with an 8HP Briggs commercial engine. I cleaned the carb, changed oil and plug but it only backfires when I pull the handle. No kickback. I'm at a loss. Could this be a flywheel key? Points? I'd just like s place to start as I have never encountered this. Thank you!

[@laciLaszloM]

l have a briggs and Stratton that has ripped out the lead out of my hands......l have checked the shear key and its ok.....l have empty the sump and checked the cam and crank gears - both line up with the timing markers......so lm at a lost to why the timing is out but can't find the reason......if anyone has any suggestion it would be much appreciated -thank you

[@dylanbeale4331]

I can't even pull my back it raises the whole lawnmower off the ground I have to get the key put on mine hopefully it works

[@keithtaber1712]

Check for bent crankshaft and or blade first

[@robertkibbler1564]

High from England don. Great vid. My qualcast cylinder mower with techumseh engine hit a clothes peg on the lawn. Now occasionally it rips the cord from my hand unless I find the compression first runs ok once started what do you think??? Cheers rob.

[@anthonylongdon1649]

Hi I have a husqvarna chainsaw 268XP The crankcase compression is really difficult to over come when pulling the starter cable It's so bad that as you pull the cord the chainsaw tries to pull away from your foot brace keeping the saw on the ground or as you say your fingers pulling the cord nearly get wiped of your hand I thought this to be a damaged woodruff key I had a lot of pressure on the crankshaft taper before it released the flywheel Because it was so tight to pull off I was sure the key was damaged but no its a straight as a dye Sadly I don't know what else to look at now Research just keeps coming back to damaged keyway

[@williamcampbell9513]

I have a 20 horse Intek that had a partially sheared key due to hitting an obstruction.. The main symptom was not increasing with throttle and dying. After replacing the key, it has very little improvement, slight increase in power. Is there anything else that might cause little increase in power? Also replace carb, adj. valves.

[@99carnot]

Helpful information! Congratulations on over 101K subs. Have a good weekend!

[@dalelee3901]

Backfiring through the carb.

[@unisol2287]

Donny, a good advice I can tell you is try to keep your video clips between 3 to 5 minutes length, than it would be more practical we can watch them completely ....

[@donyboy73]

thanks for the feedback, on some major repairs they will be longer though

[@unisol2287]

Very well soldier .....

[@dfields9511]

I have a mower that flywheel key is not sheared but will only run on a prime for a few seconds. Carb is clean, I suspect the internals got out of timing with the cam and crank shaft alignment got out of sync.

[@donyboy73]

you could also have a bad carburetor

[@frankcastillo5272]

QUESTION...Will flywheel key also cause gas to spit out of the carburetor?

[@chrissapp9507]

cool looking mower.

[@ianstell614]

Great video, really well explained

[@paulblackburn931]

I have another question. If a customer brings a mowers in with a no start problem? But his pull rope doesn't go back in, and a wheel is missing. Do you just fix the nostart problem?

[@diyfellow1627]

What about afterfire? I have a 22 inch Toro self propelled with kohler engine. Runs great although when i let go of handle to shut it off it will backfire and give almost like a clanking noise.

[@paulbillings1791]

Running over the simplest trash can cause this. Six pack rings,grocery bags,anything that the blade can pick up and snag under the deck can shear the key. Even worse,there's a key for the blade adapter,that is not replaceable,you have to replace the blade adapter itself. Blade sharp. Cut high. Pick up trash. Don't loan out your mower. You know how people drive a rental car? They are the same way with a mower that doesn't belong to them.

[@MCscarfacematt]

ive got a few of the symptoms but not sure how i could have sheared it, as the engine is a gx390 clone on a golfcart so there would be nothing to hit and cause the crank to stop. it knocks on start up, it kicks backto the point it broke the teeth off the recoil but only when its cold and i dont plug the block heater in. it also back fires at cruising speeds and at shut down but only sometimes

[@GrassDaddy]

Very interesting! I appreciate all these videos.

[@AudreysKitchen]

To clarify, an otherwise healthy engine with a sheared flywheel key will pass a compression test just fine, right? I’m trying to diagnose my scooter and am a little confused at the moment as I seem to have good spark but am still not getting the engine to start even with starting fluid sprayed into it. Which leads me to thinking it must be either compression or timing. I’m pretty new to this stuff and have been learning a lot as I’m fixing up this old bike, but unfortunately this issue is new and it’s been hard to diagnose. Picked up a compression gauge, so I’ll be testing that in the morning.

[@dangeroustoys5668]

i had one spin 180 degrees out of time, itd spit gas out of the carb and suck air in the muffler- haha. changed the flywheel key and it fired up like nothing happened. another thing you should add if your mower is old enuff, to like have points, when the flywheel is removed, a new key should be used. thanks for the tip.

[@24revealer]

Just got a free Coleman Powermate Maxa 3000 Generator with a tecumseh 5.5hp engine off Kijiji. Guy said the motor was seized, but when I got it home it tuned over. I spent some time cleaning the green? gas out of it and dirt and it just won't start. Finally realized the carb was blowing air out of it and the exhaust was also sucking air and exhaust in also. I think it must be the flywheel key now. Something is our of time. Thanks for the comment dangerours toys56 and Donny great video as always.

[@marshallborder9089]

DonyBoy is a small engine Technician

[@AChi__]

What an excellent explanation. Thanks man 👍🏽

[@juntjoonunya9216]

That is one interesting looking mower

[@robnation2475]

Check this if you hit a tree stump with a mower. Unlikely problem for a pressure washer though.

[@gwaynewilcox2702]

I am rebuilding a Predictor 4000 generator and the engine knocks and bounces. I Try this. I have done everything else. Thanks!

[@zazarays]

What if its now starting after replacing the Flywheel key (im certain i put the key in properly and the slot was undamaged) But, the starter rope pulls back sometimes and sometimes smokes out the air intake when it fails to start And runs some wat weak misfiring? Timing Gear? I just realized i put a Chinese cheapo ignition coil on it. Maybe out of line

[@aegan8329]

The oil everywhere is a symptom I didn’t know of yet, I think I may have this issue on a little go kart I built... I’ll examine it tomorrow. I want to put a cast iron flywheel from a snowblower because it can idle better with more inertia, but this may do the trick for now

[@aegan8329]

Update: I replaced the key, it broke. Then I aligned the timing to be a few degrees retarded and welded it all together. Then it broke the crankshaft where I welded, so I welded more. Then it broke a quarter inch off the end of the crankshaft. Then not only did I run out of welding wire, but I quite literally ran out of crankshaft to weld to. So, last ditch attempt, I retarded the timing even more and drilled through the crankshaft and flywheel diagonally, and drove the beefiest wood screw that I could find through. Guess what, it broke. Now I’m screwed because that’s the only engine I had around with the long crankshaft on the work side... it’s one of those days where nothing works

[@J-dogg-2007]

My fingers hurts so bad because I hit a hard object while I was mowing and the engine suddenly stopped and then when I tried to pull the rope, it pulled out of my hands so hard

[@TRUONGSPORT]

Rewind Starter Pull

[@YahFllr]

I have a generator that is backfiring into the carb and will not run. I've been asking myself the question, how does the timing get off when there is no adjustment to correct it. The coil can only be adjusted for gap only. The ideal of a sheared key is something I never thought about. I'll be checking it first thing in the morning!!!

[@donyboy73]

also check valve adjustment

[@YahFllr]

donyboy73 they where good. i even increased the gap to see if that would help, it didn't! next thing I'm going to do is pull the flywheel and check the key to see if its broke or missing!!

[@A-r-o-h]

I had an issue with my mower that mimicked a broken flywheel key. Turns out the spark plug was fouled.

[@jimmysegovia2688]

thank you for sharing!!!! very good stuff! to know.

[@jacksonfev]

Your video supports my conclusion that my timing is out of whack. My buddy borrowed my mower and hit something hard, it even sheared off the bolt for the blade. I repaired it but the cord kept kicking back on me. I'll check that flywheel key next.

[@josephalan2094]

Never loan out small engine equipment of any kind unless you are able and willing to replace it at your cost.

[@marknye51.thefixitguy]

Donyboy.. what about a honda gcv190 pressure washer. I went to start it and it almost broke my hand.😢

[@Icefury]

Hi Donboy76, really appreciate all your video has saved me a bundle! Question for you, have a v-twin Kohler Command engine. Hit a rock on the lawnmowing deck which bent the blade and broke the mandrel. Easy fix there, but engine has been "off" since the encounter. Engine starts fine, but seems to missing a bit and engine vibrates a bit (no deck engaged). Power seems lower and when I shut it down, the engine runs on sputtering for say 3 seconds before coming to a stop (always shut down promptly before). In your professional guesstimation, does this sound like a partially sheared flywheel key or a bent crankshaft (is that possible on Craftsman GT3000)? Really appreciate any feedback you could offer me!

[@bfaraguna26]

riding lawnmower D 105 brigs and straton 17.5 hp .I had 3 starters replaced as gears on starter would break after 2 day period. Would shear pin of flywheel cause that ?

[@carlodonnell146]

Do magnetos go bad somehow, I hit an object and then the briggs/stratton won't start w/new coil, no spark and the the key is not sheared. I can't find a oil low cut out sw. so far.

[@Bikedueder]

Soooo. MY craftsman mower with a Briggs engine recently ran fine after hitting something, but I found the key was sheared. therefore since I needed to mow now, I tried cranking it. Nothing... FOund the flywheel key was sheared halfway, so replaced that, new coil, new spark plug, everything as far as maintenance parts was replaced. Still completely dead. No kickback on the pull cord, no fire, getting gas because the plug is wet.... I even sanded some rust off the flywheel pickups for the kill switch and coil. Still not running, not even a pop, There is some compression, because I can feel it and hear it...

[@Bikedueder]

Did I get a defective coil maybe? Was briggs & Stratton branded,...

[@trevorpitts7401]

2002 LT160 riding lawn mower. Hit a rock and the left blade now won’t cut and spins freely. So do I just change a shear pin? On one side?? It still starts and the right blade cuts. Do I have to re-time anything? Or just change and go.

[@AudreysKitchen]

I’m wondering if this is the issue I’m having with my 250 CC Honda scooter

[@seanwalker5157]

Hey thanks Donny this sure helped a lot

[@fvfgx]

Is this why my Tecumseh 16 hp Back fires from the carb and not of oil buildup on the bottom of the engine case I checked the valves and cleaned the carb 3 times Same thing The engine case get vary hot Will try to replace the spark plugs and coil also

[@justincrawford1325]

I hit a rock and my mower completely died immediately. Wont even turn over at all. Battery is completely charged and acting like its dead. Is that still the shear key?

[@raulsern985]

Very helpful

[@petefroud5308]

One thing you get a puffing noise through the motor when trying to pull it over. Like a misfire.

[@christopherholtjr4892]

could i have a sheared flywheel key on my snowblower. I tried starting my snowblower and after a couple of tries with the electric start i heard a loud pop and now it wont start. i replaced the spark plug and the primer line do to were on the line and the spark plug is 4 years old. i have a tecumseh motor