Last time I had a similar issue it was a bad ground. I know the ground is now good (4 ga from batt to starter bolt) as is the positive wire which was also replaced bigger and better. Can a starter motor simply turn slowly if it is bad? Solenoid kicks right every time but engine turns over slow.

When I say slow I mean if your battery is about dead but has just enough to turn it over - thats the speed Im talking about here. Battery is brand new. I also have a battery charger with jump start and doesnt help. Pulled plugs and rotated by hand. All seems good there.

I guess I dont want to change the starter if I dont have to. Of course that means Ill have to dig through my stash of stuff and find one.

Ideas?

 

Seems to be intermittent issue. I went out earlier and cranked it and it cranked normal. Then I went to Auto Zone to order plug wires and when I came back it is going slow again. Im kinda pissed because I could have drove it around a bit today.

Is what I am explaining sound like a starter issue or something else?

 

Figured it out. Come to find out the Neg connector at the battery was SLIGHTLY corroded. Apparently not quite a good enough connection to let the starter go fast but enough for everything else to work properly. There you have it.

 

Glad you found your issue.

To answer your initial question, it is possible for a starter (or any electric motor) to fail in such a way that it loses torque. Can happen through excess brush wear or contaminated brushes or commutator, through mechanical binding (usually results in burnout) or a shorted winding that is reducing the effective number of turns in the motor, and thus the available force. Since a shorted winding also drastically increases current, they tend to burn open not too long after.