Pull cord jerking back

[20GT]

I have a Cub Cadet SRC621.
We just put a new coil on it.
It pulled easy and after a few it started.
We let it warm up, then shut it off.
We tried to start it again but the pull start was hard to pull. Sometimes jerking back.
I've looked on the net, a sheared off key was the possible solution.

But if that was true why did this problem only occur when the engine was warmed up?

 

[ferrisbestyet]

I have a Cub Cadet SRC621.
We just put a new coil on it.
It pulled easy and after a few it started.
We let it warm up, then shut it off.
We tried to start it again but the pull start was hard to pull. Sometimes jerking back.
I've looked on the net, a sheared off key was the possible solution.

But if that was true why did this problem only occur when the engine was warmed up?

the coil also acts as the timing be sure it is in the same place you took the old one off of if this is the coil than is under the flywheel it acts as the trigger coil... on some models

 

[Rivets]

Please post the engine numbers. We can't answer your questions until we know what we are talking about. If you removed the flywheel when installing the coil and the flywheel was loose, the engine will start properly until the key starts to shear, then kickback.

 

[bertsmobile1]

Some times if the coil retining bolts are not quite tight enough the coil can shift a little when it gets hot.
It is called "settleing down"
As the air gap also controls the timing, if the coil shifts a little the timing will change a lot.

I tend to be a too loose man rather than a too tight man ( except when spending money ).
I have had this happen to me a couple of times which I don't mind too much because it is a lot earier to tighen the bolts a little more than removing one that has broken slightly below the surface.

This happens most often when installing a new coil and I now make it a rule to fit new coils with new bolts so I can use my tiny tension wrench to check the tightness without fear of breakages and of course the custome pays for the new bolts but I can't charge the customer for the time spent removing the old ones If I broke them during installation.
If they broke during removal, no problems because the ustome would already be aware of this when I quoted for a new coil .