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Post by KSR Moto on Jun 27, 2018 2:36:02 GMT -5
My engine for some reason started to kick back while using kick starter, it kicks back so hard that it jammes my kick starter, and I can feel it pushing my leg back into 1:00 position and I am not talkig about spring! The engine is doing this, it kinda missfires in the wrong direction pushing my leg with strong force back and jammimg the starter
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Post by 90GTVert on Jun 27, 2018 6:34:30 GMT -5
Have you done anything that could advance the ignition timing?
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Post by GrumpyUnk on Jun 27, 2018 8:43:31 GMT -5
If something happened that made the crankshaft come to a QUICK stop, or ???, the flywheel on the end of the crankshaft could have moved if the 'key' got sheared. Stopping the crankshaft while spinning at several thousand rpm would make the relatively heavy flywheel still want to keep turning due to inertia.
If the nut was not tightened sufficiently, the flywheel can continue to rotate and shear the key.
Check by rotating the crankshaft to TDC, checking using the cam position, poking a pencil down the sparkplug hole to verify TDC, and check the mark on the flywheel(commonly mis-named the stator) for alignment with the T mark.
A flywheel that has rotated due to quick stop can cause the spark timing to be advanced more than normal, as the flywheel will reach the spark pickup point earlier in the crankshaft rotation, and set off the plug.
Kickback is a very common result of sheared keys and advanced timing.
tom
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Post by humanshield on Jun 27, 2018 9:36:38 GMT -5
The posts above covered everything mechanically pretty good. Not much to add. The answer probably lies in one of the posts above. BUT......if after checking all of the above carefully and you find nothing wrong mechanically, drain the fuel and try fresh, GOOD quality gasoline from Mobile, Chevron, Exxon or Shell (if you by any chance used old gas or gas from an off brand station.)
You could also try Premium.
Octane determines fuel volatility. If it gets too low you can get compression misfires like a diesel sort of. Nasty pre-ignition in essence. That's probably not it....but just throwing it out there in case. |
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Post by KSR Moto on Jun 27, 2018 11:14:24 GMT -5
Have you done anything that could advance the ignition timing? No nothing, not sure what previous owner did but I haven't touched the timing |
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Post by KSR Moto on Jun 27, 2018 11:20:11 GMT -5
If something happened that made the crankshaft come to a QUICK stop, or  , the flywheel on the end of the crankshaft could have moved if the 'key' got sheared. Stopping the crankshaft while spinning at several thousand rpm would make the relatively heavy flywheel still want to keep turning due to inertia. If the nut was not tightened sufficiently, the flywheel can continue to rotate and shear the key. Check by rotating the crankshaft to TDC, checking using the cam position, poking a pencil down the sparkplug hole to verify TDC, and check the mark on the flywheel(commonly mis-named the stator) for alignment with the T mark. A flywheel that has rotated due to quick stop can cause the spark timing to be advanced more than normal, as the flywheel will reach the spark pickup point earlier in the crankshaft rotation, and set off the plug. Kickback is a very common result of sheared keys and advanced timing. tom None of that happened,this is common problem on lawn mowers that hit rocks and get flywheel key sheared, I dont have the tool to pull flywheel off so I cant check it |
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PirateLabs
Scoot Enthusiast
Posts: 296
Location: Bowling Green, KY
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Post by PirateLabs on Jun 27, 2018 13:29:22 GMT -5
If something happened that made the crankshaft come to a QUICK stop, or , the flywheel on the end of the crankshaft could have moved if the 'key' got sheared. Stopping the crankshaft while spinning at several thousand rpm would make the relatively heavy flywheel still want to keep turning due to inertia. If the nut was not tightened sufficiently, the flywheel can continue to rotate and shear the key. Check by rotating the crankshaft to TDC, checking using the cam position, poking a pencil down the sparkplug hole to verify TDC, and check the mark on the flywheel(commonly mis-named the stator) for alignment with the T mark. A flywheel that has rotated due to quick stop can cause the spark timing to be advanced more than normal, as the flywheel will reach the spark pickup point earlier in the crankshaft rotation, and set off the plug. Kickback is a very common result of sheared keys and advanced timing. tom None of that happened,this is common problem on lawn mowers that hit rocks and get flywheel key sheared, I dont have the tool to pull flywheel off so I cant check it I believe you can still check it by lining up the 2 holes in the cam gear with the top of the head and then, open the timing port to make sure the timing mark is lined up with the "T" stamped on the bracket. Should only take maybe 10 minutes or so. Just a thought. Bill |
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Post by KSR Moto on Jun 27, 2018 13:57:45 GMT -5
I checked that and it is okay but I really need to pull it off to see
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, the flywheel on the end of the crankshaft could have moved if the 'key' got sheared. Stopping the crankshaft while spinning at several thousand rpm would make the relatively heavy flywheel still want to keep turning due to inertia.