Tip & How-To about Garden

Lawn-Mower won't start

Hi, when your Lawn mower is not starting, follow the steps and instruction below to troubleshoot and fix it..

Engine seized If you are unable to pull the start cord or if the electric starter will not cause the engine to turn over you may have a seized engine. Check the oil level, if there is no oil in the crankcase the piston may have become fused to the cylinder wall. Spraying a penetrant or lubricant into the cylinder through the spark plug hole can sometimes loosen the piston otherwise it is likely the engine will need extensive repair work.

Battery dead Check the battery to make sure it is completely charged. Also check the cables to make sure they are tight and the battery posts are clean.

Spark plug fouled or defective The spark plug may be loose and need tightening, the spark plug wire may be damaged or disconnected, or the spark plug may be clogged with oil, gas, and combustion residue. If it is clogged it can be cleaned with a wire brush. You may also need to reset the spark plug gap. The spark plug gap can be checked and adjusted with a spark plug gauge to measure the gap between the center electrode and ground electrode on the end of the spark plug. Check the required specifications in the owner's manual. If it's badly damaged, replace it.

Recoil broken If you pull the recoil starter assembly and it pulls too freely or doesn't retract after pulling it there may be a broken or jammed spring, pulley, or cord. If the cord retracts but pulling the rope doesn't crank the engine, you will need to remove the recoil starter assembly to determine the cause of the problem.

Air-fuel mixture Small engines need the proper amount of air and fuel (14:1) in order to start or run properly. An air-fuel mixture that is too lean (too much air) burns hotter and may cause rough idle, hard starting and stalling and a lot of misfiring. Check the choke to make sure it is not stuck in the open position otherwise the carburetor may need to be cleaned or adjusted. An air-fuel mixture that is too rich (too much fuel) is usually due to a dirty or clogged air filter or the choke being stuck in the closed position. The choke should be in the closed position when starting a lawn mower, however if the choke remains closed the engine will not start because the fuel and air mixture is too rich.

Oil into carburetor and/or combustion chamber Oil can leak into the carburetor if the lawn mower has been tipped on its side (carburetor is not up in the air). If this happens the carburetor must be completely cleaned out using a brush or rag and a spray or liquid carburetor cleaner.

Starter switch or motor If there is only a click sound when trying to start a lawn mower with an electric starter there may be a problem in the electrical system. Use a multimeter to test the starter switch, alternator and any other electrical component. Check the owner's manual for meter settings, speed, and readings.

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Craftsman tractor. Will not crank over ,

Mike, problem could be a lot of things, weak/dead battery, starter/solenoid faulty, bad fuse/wire, Faulty safety switch, seized engine, engine in need of valve adjustment,etc. You may have to have checked, diagnosed and estimate for repair by a small engine Tech. Check the attached links,instruction and guides, Good luck
"I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info."
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Aug 23, 2016 | Craftsman Garden

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mower won't start

Glenn, check the lawn mower engine trouble shooting links below for engines that do not start.
"I hope this helped you out, if so let me know by pressing the helpful button. Check out some of my other posts if you need more tips and info."
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How to fix stuck pull cord of a 22 inch Toro Recycler lawn mower

Is the engine seized?. Try turning the blade and if it won't turn then you have a seized engine. If that is ok your recoil has a stuck part possibly something has broken off inside. If it's an older model try shooting WD40 inside the recoil as it could be rusty.

Jul 25, 2014 | Toro Garden

1 Answer

lawn mower is a craftsman model ys4500 was running fine 10 min ago. Front end started to shake and engine made a god awful noise and died. Mower was on blacktop road when this happened. What could it be?

Ooooh, sounds bad. Can you turn the engine by hand? If not, engine is seized. Can you turn it freely a little and then it hits a hard stop? Then the connecting rod is broken. The good news is a seized engine is not guaranteed to be a death sentence for the engine. There are ways to free it, then inspect for damage. The connecting rod, may have done damage to the block or not, depends on where it failed. The connecting rod requires disassembly of the engine to fix.

How was your oil level when it happened?

Aug 22, 2011 | Craftsman 21 Hp 42" Deck, Ys 4500 Lawn...

1 Answer

I can't figure out how to start the mower. Unable to decipher the Instruction booklet. Believed to be series 625. with the following: Self propelled electric key start with a primer. No choke present

Hi and welcome to FixYa. I am Kelly. The primer is the choke. You press ther primber bulb 3 times with the gas tank full and then hold / grip the safety bar at the top of the handle against the handle then either use the key start or recoil to start it. Just make sure the engine crankcase is filled with the correct amount of oil before starting. Sorry for being brief but it really is that simple.

Thanks for choosing FixYa,


Nov 12, 2010 | Poulan Pro 22inch 625 Series Briggs ...

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