ire, engine would die, wait a few and started again. finally, just backfires while turning over.
17.5 hp 42 in. Deck Lawn Tractor – CA Model

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The engine should be an OHV type. You could try adjusting the valves under the OHV cover. Kinda like the valve lash on cars. When the valves are at rest you can set each one to about .004 with a feeler guage. You can look on youtube for a video one adjusting lawnmower engine valves. Seeing it is easier to understand then reading it.I hope that this helps you get it fixed.

How to Identify and Fix Common Gardening Problems ?

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Low fuel pressure can cause a backfire when there`s too much air and not enough fuel in the combustion chamber. This can be rectified on lawn mowers with speed settings by simply increasing the speed and thus increasing the fuel supply. Another possible cause is a failing fuel pump or even an old fuel filter.
If you pull the cord and hear your engine turn over, but your mower is not starting, the most common reasons for this are low fuel, a broken gas valve, or a bad choke fault. A broker spark plug could also be the culprit. You may also have to change the fuel pump if it does not get fuel to the ignition system.
Backfire, or more accurately “after fire” when it occurs when stopping an engine, is caused by unburned fuel/air mixture being ignited by the heat of the muffler.
Excessively lean carburetor settings can contribute to backfiring. If the mixture is too lean, it may burn very slowly and unevenly. This condition, in turn, may result in burning mixture remaining in the cylinder until the beginning of the next intake stroke when it can ignite the incomming air/fuel mixture.
If your tractor cranks, but won`t start, you`ll want to look at a few different engine components. Is the fuel making it to the cylinder? Check the fuel level, the shutoff valve, and the fuel filter. If those components look ok, air might not be making it to the cylinder.
A dirty carburetor is the most common cause of a lawn mower that starts and then dies. Other possible causes include: Stale/Dirty Gas. Faulty Choke.
This can be caused by a faulty mass airflow sensor or a clogged engine air filter “choking” the engine and not allowing enough oxygen to flow into it. Or, it could be caused by leaking fuel injectors forcing too much fuel into the engine.
One of the most common causes of a sputtering engine is an issue with the vehicle`s fuel system—the filter, pump, and injectors. These three critical components work together to ensure fuel flows smoothly from the fuel tank to your engine`s fuel injectors, and then pumps into the engine evenly.
Another possible cause of your backfire is a spark plug refusing to “spark” when the exhaust valve opens. If the air/fuel mixture has become too rich, unburned fuel is left in the exhaust system. The misfired spark plug ignites the rich air/fuel mixture, causing a loud “bang” in the tail pipe.
Another possible cause of your backfire is a spark plug refusing to “spark” when the exhaust valve opens. If the air/fuel mixture has become too rich, unburned fuel is left in the exhaust system. The misfired spark plug ignites the rich air/fuel mixture, causing a loud “bang” in the tail pipe.
Backfires and afterfires are worth paying attention to since they can cause engine damage, power loss, and decreased fuel efficiency. There`s a variety of factors that can cause your car to backfire, but the most common ones are having a poor air to fuel ratio, a misfiring spark plug, or good old-fashioned bad timing.

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My lt1000 turns over and while turning over backfires. does not start. Started backfiring a couple weeks ago while in operation. would backfire, engine would die, wait a few and started again. finally, just backfires while turning over.
ANSWER : The engine should be an OHV type. You could try adjusting the valves under the OHV cover. Kinda like the valve lash on cars. When the valves are at rest you can set each one to about .004 with a feeler guage. You can look on youtube for a video one adjusting lawnmower engine valves. Seeing it is easier to understand then reading it.I hope that this helps you get it fixed.

Engineer starts, and stop – Mtd 22" Yard Machine Push Mower
ANSWER : Clean fuel system
lines
tank
carburetor main jet, float bowl
check cable/linkage adjustments

My Z5426 won’t start. When I pull out the choke and turn the key, gas starts leaking out of the exhaust system just before it gets to the muffler. Last time it did start, it ran really rough. So, I turn off the engine and then tried to restart and that’s when I noticed the fuel leak.
ANSWER : Maybe bad fuel, fuel line leaking, flooding of the carburetor, since it did start and ran rough I am assuming that the gas was left set and more then likely this gummed up the carburetor, you will have to clean/rebuild it. If you have a can of carburetor clean you may be able to spray that into there and clean it up, I would not choke it to start it as it sounds like it got/is flooded/ing. Good Luck Tim

Battery the battery is dying and it will start but, after a few mins the engine starts to sputter then goes back to idle and eventually dies. could this just be the dead battery? is that the reason the engine dies?
ANSWER : Usually, if the battery is dying, it won’t start up again.
Usually, motorized vehicles only use the battery to start the engine, then the alternator contributes all the power for actual operation.
A dead alternator or battery shouldn’t ‘sputter’, they would just stop dead.

If the engine will start, run and then sputter…there is a fuel problem.
1. There may be a ‘cut-off’ in the fuel line which is in the off postion. It may look like a thin, flat wing-nut.
2. The gas may be contaminated with water residue if the gasoline has been sitting a long time. I believe you can get some water treatment to fix this without having to dump the fuel tank contents.
3. The fuel line is blocked with dirt somewhere, I would check the fuel filter and work backwards from there.

Exmark 44 Mower bogs down going forward
ANSWER : When you say ‘going forwaed’, is that while mowing or does it do it without the blades engaged or ‘not mowing’?

I have a John Deere L118 Limited Edition (w/ 20 HP B&S engine), which I purchased about 8 years ago. It ran well with few problems up to late this summer. I believe the problem started when I accidentally filled the tank with some stale gasoline – the tractor turned over, but would not start. I drained the fuel tank and filled it with fresh gas, but it still would not start. When I use starter fluid, the tractor starts for 4-5 seconds, and then cuts off. I installed a new fuel filter. The connections in the fuel line seem tight, so while the problem might be the vacuum fuel pump itself, I do not think it is due to a leak in the line. I disconnected the fuel line at the carburetor — fuel flows through the line at start up. But when I put the fuel line directly into the air intake (with some starting fluid), the engine still cuts off in about 4 seconds. I am not sure if the pump simply is not drawing enough fuel into the carburetor. I understand that, if it is a problem with a safety cut-off, the engine would not start at all (even for 4 seconds). My thought was that the problem may be a gummed up carburetor, but that would not explain why the tractor does not start when I feed fuel directly into the carburetor. Any thoughts about other things I can try before bringing the tractor to a mechanic?
ANSWER : Just take the carb bowl off its easy one bolt on the bottom of it get the old gas out flush all old gas out of tank and line then it will run trust me i know

My mantis tiller with a honda gx22 engine starts then shuts off after approx. 30 sec.
ANSWER : If your unit has a primer bulb, start your engine . When it starts to die push your primer, if the engine comes back to life you have a carb issue.

Why does it backfire on warm restarts? – Craftsman 42 In. 21Hp Briggs & Stratton Hydrostatic Turn Tight Yard
ANSWER : Readjust the valve clearances
B& S engines are renowned for stretching the valve stems during use
creates hard /no starting when hot
check for coil wire touching the engine and shorting out