Occasionally, the starter just freewheels (just motors) instead of the bendix engaging with the ring gear. This sounds like a starter replacement to me. Where is the starter located, and please post all the short cuts that hopefully exist.
Thanks

 

You could be absolutely correct !
However, please be aware poor connections at the battery or problems with the battery cables can also produce these symptoms.
It is not a nice feeling after you install a replacement starter and still have the same problem. So,,,,,,,,,,,,,either do some serious checking or have it checked by a shop that can check that out .Sometimes we get lucky and guess correctly, but if not, short cut time just flew the coup.