Why does it backfire about 10 seconds after shutdown? I've tried pulling throttle to idle for 30 seconds before shutdown, but it still backfires once most of the time.
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The solenoid on the bottom of the carb may not be working or not sealing and gas drips passed the valve
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Why do I sometimes hear a loud backfire noise when I shut off my engine? 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.
There might be more than one reason why a snow blower backfires. Possible reasons for a backfire include stale fuel in the tank (particularly ethanol fuel), a dirty carburetor, an air to fuel mixture that is too lean, a bad spark plug, and a poorly designed exhaust muffler.
If too much fuel is added to the engine, it may not all burn up before the exhaust valves open — letting unburned gasoline into the red-hot exhaust headers, where it can combust and lead to a backfire. Too much fuel could be getting into your engine due to damaged and leaking fuel injectors or bad engine sensors.
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.
The problem with the Holley power valve is that it is the most sensitive circuit in the carburetor. The little rubber diaphragm has a tendency to tear or just plain fail at usually the most inopportune times. It is especially vulnerable to engine backfires.
However, if the valves become bent, they won`t form a proper seal. That`ll allow air and fuel to flow back into the intake or into exhaust, where it will combust. Luckily, this is a very uncommon reason for a modern car to start backfiring.
The opposite problem can lead to the same result. If there`s too much air in the cylinders at the time of the spark, and not enough fuel, the spark won`t be able to ignite all the fuel at once. Yet again, leftover fuel vapor will flow into the exhaust and could combust there in a backfire.
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.
Touching back on air to fuel ratios, a vacuum leak will likely make your engine run “lean” (too much air.) This means the engine cannot efficiently ignite fuel in the combustion chamber. When fuel builds up in the cylinders and combustion occurs, it will expel a backfire.
On the other end of the spectrum, a bad fuel pump, vacuum leak, or clogged fuel injectors could cause an air-fuel ratio that`s too lean; that is, it has too much air and not enough fuel. Though this is the opposite problem, it can also cause a backfire as vapor escapes into the exhaust and combusts there.
Too small of a gap may give too weak of a spark to complete the combustion process within the engine; too wide of a gap can lead to the spark plug not firing correctly, causing misfires at high speeds.
There are a number of things you may do while operating your mower that can cause a backfire, and there are way to avoid them. The primary cause of a backfire is decelerating too quickly. The simple fix for this is just to lower the engine speed a bit more gradually.
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Gas leaking from carb when not in use.how to fix.
Clean the float needle and check its not ridged where it seats ! if so replace !
Valve adjustment intake/exhaust – Craftsman Kohler Courage 26 hp 54" Garden Tractor (CA) ()
I’ll bite, what’s your question Mike? If you are looking for a how to, you can probably find it at the manufacturer’s website, without going into too much detail however I can offer you a general approach.- Remove the front hood of the mower and the shroud if it has one.- Disconnect the carb, and exhaust and move it aside.- Remove the Spark plug- Carefully remove the valve cover in the front of the engine.- Look up the proper valve adjustment settings for your model.- Get the engine at top dead center.- Take measurements and adjust the valves accordingly.- Clean the valve cover itself, and where it’s going to be seated.- Apply a thin coat of gasket sealant, put the cover back on.- Wait for the sealant to bond (depends on manufacturer specs_- Fire it up.Keep in mind, this is a general guide, see your manufacturer’s manuals and technical diagrams for more details.
I HAVE A CRAFTSMAN ZT7000 MOWER WITH A 20HP KOHLER SV600S ENGINE.I WENT TO START IT AND IT WAS HARD TO START. I CHANGE THE FUEL FILTER. IPUT A NEW PLUG IN. I CHANGE THE FUEL . NOW IT WILL START BUT IT WON’T TAKE GAS. IT RUNS HOT AND SEEMS TO BACKFIRE FROM THE MUFFLER. COULD IT BE THE TIMEING OR VALVES?
Sounds like the float in the carb is leaking by the set.
Kohler engine 15.5 turns over but will not start
Make sure you are getting spark at the spark plug, to do this:Remove your spark plug and check to be sure you are getting fire at the spark plug.You do this by grounding the plug on the head of the engine and pulling the crank rope, if you are getting spark then:
Sounds like you have dirt/debris in your caburetor jets,fuel passages or a diaphgram that is becoming non-flexible. Check/Clean/Replace your Air Filter, a dirty air filter can make your engine run to rich with fuel.
Note: ALWAYS USE COMPRESSED AIR TO CLEAN YOUR JETS AND PASSAGES, VERY IMPORTANT.
Note:Before you disassemble the carburetor:Mark each piece with a awl, or some kind of instrument that will make an alignment scratch before you disassemble the carburetor into separate pieces.That way you will know which way it goes back together when you reassemble it.
Sometimes you can get by with priming the carburetor or by using starting fluid and letting it run a few times like that, and it will flush the gunk out of the jets,but most of the time you will need to rebuild the carburetor.Be sure to check your fuel tank for water and dirt/debris, if there is water/debris then you need to clean your tank.Check you fuel line condition after a while they will degrade and need replacment.
Check/Clean/Replace your fuel filter if you have one.Make sure you are using fresh fuel.If the moweris over a couple of years old, then I recommend that you buy and install a new carburetor repair kit,because the diaphragm will get hard and that will cause it to be hard to crank.The diaphgram may look good and flexible, but it can be deceiving and not act as a fuel pump as it should because it has become too hard and will cause hard starting,start and run and shut off, etc.
When you clean your carburetor, I recommend that you use a laquer thinner type cleaner to clean and dissolve the laquer build-up in the float and needle jet passages.Be sure to remove all plastic and rubber parts before using the laquer thinner because it can dissolve the plastic parts and render them unuseable.Be sure to use COMPRESSED AIR to blow out all the fuel and air passages.The higher air pressure is needed to blow some of the trash/debris from the fuel or air passages.Be careful when blowing out the passages, because there are sometimes small rubber type seats in the bottom of some of the passages.Keep in mind that the float (if you have one) for the carburetor must be level when you go to reassemble the carburetor or follow the instructions you get with the carburetor kit, or you could also ask the parts man that you get your kit from.When you clean your carburetor and remove the jet screws, you will first need to lightly seat the jet screws.But before you lightly seat the jet screws count the number of turns it takes to seat the jet screws from their original position.Be sure to mark the turns down on a piece of paper.That way when you put the jets back in, you know to lightly seat them first and then turn them back out to their original position before you started.
After you have the carburetor rebuilt that should solve you starting problem.
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Wont spray – Kohler NET HP COURAGE XT-7 SERIES VERTICAL ENGINE
I hope the engine wont spray… if it’s a pressure washer thats not spraying the name of the unit would help… but does it build pressure but doesn’t spray – check the wand does it even build pressure ??? no – replace pump
I have a troybuilt bronco riding tractor with 18horse Kohler twin engine. it cranks but wont fire. It is getting fuel to the carb. If I spray carb cleaner into the carb it will run for a second then quickly die. I’m wondering of the electric backfire eliminator is faulty and shutting off the fuel supply. Any suggestions on how to trouble shoot this? Thank you!
You most likely have a problem in the carburetor. It will need to be disassembled and cleaned. In regards to the backfire eliminator, you can remove it (caution, clamp off the fuel at the fuel line or you will be draining the fuel tank throught the carburetor. With the wire harness removed you attach two wires to the prongs and put one to positive and the other to negative and it should move. It should audibly click when it does, operates quickly.I hope this helps, if any questions let me know.
27 hp kohler v-twin ohv backfires, and @ times blows white or black smoke
SOUNDS LIKE IT HAS BAD GAS AND THE VALVES NEED RE SET YOU MAY WANT TO FLUSH YOUR FULE AND CLEAN OUT THE CARB LET ME KNOW IF THIS HELPS
2011 craftsman kohler courage clutch linkage – Craftsman Kohler Courage 26 hp 54" Garden Tractor (CA) ()
That should have a electric clutch not a linkage