The starter just spins but wont engage, the battery is fully charged. It was working great and all of a sudden it wont start today.

Thanks

 

Sounds like the Bendix (that internal spring) is out. If it is just sticking sometimes a light tap with a hammer will do it.

 

Another reason that you should add a pull rope lke on the 87 and 88's. It could be the starter clutch. I had the same problem but backwards. it would not dis engauge. If the starter is spining it might also be the gear that attaches the starter to the flywheel.