john deere 318 breaking starters

[goatfarmhand]

i have a 318 john deere mower with a b43 onan engine.the starter went bad and i replaced it. after about 10 starts the flange broke off of the starter. i put another starter on the mower and after a dozen starts it broke at the same place. i have a .025 backlash on the flywheel to the starter and everything looks fine. points are set at .016. anyone have any ideas of what might be wrong. this thing is driving me crazy.ive put another starter on but afraid to put it back in because the way my lucks going it will break again.if anyone has any ideas i would appreciate them letting me know. thanks goatfarmhand

 

[Fish]

i have a 318 john deere mower with a b43 onan engine.the starter went bad and i replaced it. after about 10 starts the flange broke off of the starter. i put another starter on the mower and after a dozen starts it broke at the same place. i have a .025 backlash on the flywheel to the starter and everything looks fine. points are set at .016. anyone have any ideas of what might be wrong. this thing is driving me crazy.ive put another starter on but afraid to put it back in because the way my lucks going it will break again.if anyone has any ideas i would appreciate them letting me know. thanks goatfarmhand

Take out the plugs and rotate the flywheel by hand and inspect all of the teeth.

Has this been your mower for a long time? Or have you just obtained it recently?

 

[goatfarmhand]

Take out the plugs and rotate the flywheel by hand and inspect all of the teeth.

Has this been your mower for a long time? Or have you just obtained it recently?

flywheel looks great ive rebuilt the motor and it seems to run fine but after a few starts the starter breaks.only thing ive noticed is a couple of times when you cut it off it would backfire a little bit. i didnt think that would be the problem though since the starter isnt being used.

 

[goatfarmhand]

i havent owned the mower long but it was my nextdoor neighbors and he burned a piston so i got it from him. however ive seen it mow every week

 

[Fish]

If it isn't an alignment issue then with the motor vs. starter, then timing would come to mind. Have you rechecked the flywheel key?

Also, the point gap should be @ .020-.022, if memory serves me. It has been a long time....

 

[goatfarmhand]

If it isn't an alignment issue then with the motor vs. starter, then timing would come to mind. Have you rechecked the flywheel key?

Also, the point gap should be @ .020-.022, if memory serves me. It has been a long time....

i pulled the flywheel off and key seemed to be ok as well as the flywheel. i originally set points at .020 but after reading the john deere tech manual it called for them to be .016 so i set it back to that.ive worked on mowers my whole life and no expert but this is really weird to me.one guy said that ignition switch could cause that but it looks like if it shorted etc you could probably hear the starter engaging . i guess its possible to get 2 bad starters in a row but i would think that would be likely. i really appreciate your input. im at the point i dont know what in the world to do.anything you think of i will try. im putting a new ignition switch on the mower just in case thats it. the motor has to be removed to get the starter on it so im trying to get it right before i put it in again. i figured that maybe i wasnt the only one with that problem and that maybe someone had figured it out. once again thanks a lot i appreciate it.

 

[Fish]

As far as the timing being off, if it was firing while the piston was still coming up, that would cause problems. If not ignition timing being off,
what about valve timing, you are sure the marks align?

 

[goatfarmhand]

As far as the timing being off, if it was firing while the piston was still coming up, that would cause problems. If not ignition timing being off,
what about valve timing, you are sure the marks align?

im pretty sure they are right but i probably need to recheck that i know i set the valve clearance correctly provided everything else is right because i went back in and checked after i broke the first starter.i will recheck everything though.