No spark
- Thread starter captain oblivious
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!Cheeseoreno
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That happened to my uncle. It was the “Key” that breaks off to protect the motor should your daughter hit a rock. If I remember correctly it was on the shaft to the flywheel. I do remember it was a really easy, quick and cheap fix. It’s a tiny sacrificial piece of soft metal found at any hardware store.
My mower has that same trouble. The linkage under the shroud gets sticky, and I have intermittent stalls. What a pain, but a little sleuthing found the issue.
The troubleshooting procedure is being done properly so something is being overlooked.
When you don't have spark jumping the Gap at a plug, the first basic easy test is to throw a known good plug in there preferably an older dirtier one because it's easier to see the spark if you still don't have spark it's either the kill switch wire is grounded or the module is bad.
So then you have to pull the shroud off and take the small kill switch wire off of the coil and retest.
Now this means the child has to go back on because spending it by hand is not going to cut it.
If you still have no spark and you haven't taken anything else apart and you know the mower ran before, then there is a 99.999999 and however much more you want to go likelihood that you have a bad coil / ignition module / magneto whatever you want to call that too.
Something is being overlooked or if the magneto has been swapped, it's not the right one etc
When you don't have spark jumping the Gap at a plug, the first basic easy test is to throw a known good plug in there preferably an older dirtier one because it's easier to see the spark if you still don't have spark it's either the kill switch wire is grounded or the module is bad.
So then you have to pull the shroud off and take the small kill switch wire off of the coil and retest.
Now this means the child has to go back on because spending it by hand is not going to cut it.
If you still have no spark and you haven't taken anything else apart and you know the mower ran before, then there is a 99.999999 and however much more you want to go likelihood that you have a bad coil / ignition module / magneto whatever you want to call that too.
Something is being overlooked or if the magneto has been swapped, it's not the right one etc
All good recommendations but didn’t see a comment about the safety cut out switch feature. This switch is designed to prevent a spark if not assembled properly or maybe you have a faulty switch. When I reassembled my 5.5Hp Snapper mower I hand the same problem, no spark. I remembered a mower tech warn me about this feature and sure enough the blower housing tube was not contacting the safety cutout switch during re-installation because the plastic mounting flange had cracked. I re-aligned it and it started right up. See attached photos.
Hope this helps.
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You will have spark, just not at the correct timeHave you checked the shear pin in the flywheel? If it is even partially sheared you will get no spark.
We see that all the time people put them on upside down and bring them back that is the first thing we ask them. They are marked cylinder side or this side up. Hard to see but is there.
Buy one if these & test for spark in dim light. That way you know for certain that it is or isn’t a spark problem.
Maybe OP did use a spark tester. I always use mine to check for spark before buying a new coil, but I also check to see if the coil is being inadvertently grounded. If the kill switch is not being opened when you pull back the bale, the spark will be grounded and your tester will show a no spark condition. The OP said that the mower was rusty from sitting outside under a tarp. I Not much to go on but is consistent with a rusted/corroded kill switch that is grounding out the spark. You can pull the ground wire off the coil and if that gets you spark, then you know you have a good coil but bad kill switch or other inadvertent ground. Another option if you suspect the kill switch is to insert a nonconductive material between the two connectors on the kill switch and see if the mower starts. I use a 3 inch by 1/2 inch strip of plastic I cut from a milk jug so when the engine starts I can easily pull the plastic strip out and shut down the engine, which is easier than fooling with the connection on the coil. If OP has tested and excluded bad ground then I’d suggest he ask daughter if she ran over a stump or rock just before motor stopped. If so, pull the flywheel off and check for sheared key. That would result in defective ignition timing, ie: he’d have spark, but not when he needed it, so again not a condition where a spark tester tells the whole story.