Backfiring and now not running

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L

leadfarmer

New Member
Sep 30, 2011
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VA
A couple of weeks ago my china girl engine, after running fine all day, stopped idling and then quit running altogether.
I put in a new NGK B5 plug today, it was hard to start, but ran for a couple of miles. I had to keep the RPM's high or it would die. Then it quit and will not run at all. The plug is wet and I suspect a fuel issue as it seems to have spark and copression. By the way I tried a different CDI, no luck.
While it was running, it was backfiring through the exhaust and carberator.
Any ideas how to get it purring again?
 
rohmell

rohmell

Active Member
Jun 2, 2010
1,531
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New York
Check the Woodruff key that is used to hold the magnet in position on the crankshaft.
Could be missing, causing the magnet to shift position on the crankshaft, causing hard starts, backfiring, etc.
 
rohmell

rohmell

Active Member
Jun 2, 2010
1,531
6
38
New York
The easiest thing to do is to check to see if the magnet is in the right position.
First rotate the engine so that the piston is at the top of its stroke. If you have a strong light, you can probably see this thru the spark plug hole.
At this point the flats of the magnet should be at the top and bottom, and the keyway will be at 1 o' clock. You will probably need to remove the nut in order to see the keyway.

Magnet flats top and bottom:


Keyway at 1 o' clock:
 
Last edited:
L

leadfarmer

New Member
Sep 30, 2011
149
0
0
VA
My magnet is in the correct position and the woodruff key is intact. I don't have a spark. I think I disconnected the killswitch(unplugged the wires) and nothing. I am going to buy a new magneto next.
 
rohmell

rohmell

Active Member
Jun 2, 2010
1,531
6
38
New York
If you have a multimeter, you can check the resistance of the magneto coils to see if they are within specs.
 
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