Riding mower cranks but won't start
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Strictly speaking, this is true, but if you are looking for likely occurrences, generally speaking, if you put a working small engine away a month ago, it still has spark today.
It's like using a scan tool and retrieving a diagnostic code. It often tells you what system is not operating, not necessarily the exact part. You then go through diagnostic procedures to determine which part of the system is the culprit. No spark = ignition system: maybe sensors, safety switches, various wires, coil, plug, etc..
The same goes for the fuel tricks above. Once you determine its the fuel system, then you trouble shoot the exact part - maybe a plugged filter, a cracked fuel line/fitting, carb, bad fuel, plugged tank vent, etc..
I don't know how many times I've thrown parts at a problem, only to find out that my assumptions were wrong. Live and learn.
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if it is a low probability problem and fast/easy to check. Just check it. That 10 seconds or minute of time is worth knowing for sure rather than assuming. As someone above said, check the easy stuff 1st. Even if you think it is a low probability to impossible Knowing is always better. You may surprise yourself.
Have you looked at the seat cut-off switch?
I doubt it, Usually a safety switch doesn't allow the starter to turn over.
That is true regarding the other safety switches .Not true regarding the seat safety switch. If that were the case, the engine would continue to run when you get off the machine which it doesn't function that way.. That switch grounds the ignition.
I think there is no spark. He has one plug wet with fuel . That alone should atleast get an attempt by the engine to start. My thinking is the coil is either faulty, its kill switch wire is grounded or the seat safety switch.
If a spark test confirms no spark the next test would be to remove top cover and unplug the kill wire from the coil(s) and test again. The coils are self powered and do not require a connection to the mower electrical system to work. The wire to the mower is only to kill the spark when the key is off or there is an interlock issue.
Everyone, thanks for the great advice. Haven't had time to address this yet, but I'm taking note of all your suggestions.
Yes, the engine did fire briefly when I connected the buzz box with engine start feature. It probably fired more than a couple of putts, but it killed when I prematurely released the choke, and wouldn't "putt" at all again.
Planning to first check the solenoid, then will consider plugs, carb, seat switch, etc. Any idea why only one plug was noticeably wet? Hope it's not the ignition coil or other major issue.
But perhaps this fuel is "bad"? As stated already, immediately after running the engine last month, I filled the fuel tank with stored, stabilized fuel. When the engine wouldn't start a month later, I initially blamed the added fuel.
As draining the tank and replacing this fuel didn't help, I had considered flushing the fuel line (tank to pump) to make sure fresh fuel is available to the engine. Do you think that "bad" fuel could have migrated all the way through the fuel line over the past month, thereby preventing the engine from starting? Do I have to drain the line?
Thanks for your patience until I am able to investigate and report back.
Yes, the engine did fire briefly when I connected the buzz box with engine start feature. It probably fired more than a couple of putts, but it killed when I prematurely released the choke, and wouldn't "putt" at all again.
Planning to first check the solenoid, then will consider plugs, carb, seat switch, etc. Any idea why only one plug was noticeably wet? Hope it's not the ignition coil or other major issue.
But perhaps this fuel is "bad"? As stated already, immediately after running the engine last month, I filled the fuel tank with stored, stabilized fuel. When the engine wouldn't start a month later, I initially blamed the added fuel.
As draining the tank and replacing this fuel didn't help, I had considered flushing the fuel line (tank to pump) to make sure fresh fuel is available to the engine. Do you think that "bad" fuel could have migrated all the way through the fuel line over the past month, thereby preventing the engine from starting? Do I have to drain the line?
Thanks for your patience until I am able to investigate and report back.
Give the gas a sniff test. If it smells like gas and not varnish, it's good. I frequently use stabilized gas that's a year old (sometimes 2 cycle) and never had a problem. I think you are making this more complicated than it needs to be.
To be clear, this is the "couple of putts" I originally described in the opening post. After replacing the battery and the fuel, it has not "fired up" at all.
Unless its a Torch spark plug.
I think your correct, I just flipped my seat up, put the John Deere in neutral, & then turned the key over. The starter cranks like normal. I could've sworn it wouldn't allow it unless it's in neutral &/or park brake set but that doesn't seem to be the case. Interesting!
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Takes a rodent about 3 minutes to absolutely wreck the wiring in a machine, especially if stored outside in a shed (vs attached garage).
Had some type of jerks do just that to an old 87 Dakota we had for trash/brush duty. Used it to haul off some junk and parked it, went to use it again 2 weeks later, dead as a doornail. They had consumed pieces of some very important ignition-related wires in the main harness near the computer. Haha
That's definitely a possibility, and very possible in a forty year old pickup. Small engined power equipment does not have that much wiring and it is often easy to see. My focus on the carburetor and gummy fuel is really about running the numbers and getting a hard starting engine resolved by dealing with the most likely scenario(s).
In my experience with small engines that sit it is almost always fuel related. Something is gunked up in the carb. Going forward use Marine Stabil in every can and tank of gas without fail and you will avoid most problems. Does the float bowl have a drain screw or can you easily pull the bowl? Drain and take a look at the fuel and/or crud in there. Greenish gundge indicates ethanol gas gone bad due to moisture absorption.
^^Also, run your small engines OUT OF FUEL COMPLETELY before seasonal storage.
Do whatever it takes including turning lawn mowers up-side-down or syphoning fuel out of tractors, etc.
Then start 'em and run 'em dry.
Do whatever it takes including turning lawn mowers up-side-down or syphoning fuel out of tractors, etc.
Then start 'em and run 'em dry.
I stabilize my OPE fuel cans year round, stabilizer goes in before I go to the gas station to refill them. Cheap insurance and no brain farts.
I never drain any of my OPE or toys. I haven't touched a carb in years and I've got a lot of engines to maintain. Both my lawn tractors are over 20 years old for example.
I've been using PRI-G for the last few years BTW.
I never drain any of my OPE or toys. I haven't touched a carb in years and I've got a lot of engines to maintain. Both my lawn tractors are over 20 years old for example.
I've been using PRI-G for the last few years BTW.
CleanSump
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I still use Sta-Bil Marine. But I have put non-ethanol in the last couple of years because I wanted to use it in the motorcycle. Reflecting back, it's just added expense as I never had a problem using Sta-Bil and no I don't run the tank dry. That still leaves some fuel in the float bowls that can gel or turn to varnish so doesn't really accomplish what people think it does.
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