Anemic starter

[Russell Reay]

My starter has worked fine for the four years I have had my car. I recently bought a firewall insulator panel. During installation I made sure that all screws thru the firewall that were needed for ground were, in fact, well grounded. These were primarily the solenoid bolts, wiring harness ground wire, and starter button ground wire. When pushing the start button, the starter would clunk and briefly groan, but nothing more. After removing and re-attaching all connections between the battery and starter at least three times, and buying a new battery though fairly confident I didn't need it, I removed the starter and the starter switch on top. Attaching good quality jumper cables to the battery terminals and to the starter case (pos ground), the jumper cable to the copper contact on top elicited a smooth spinning reaction from the starter, but not the excited hang-on-tight response I expected. I re-installed the starter and got the original clunk--not the typical click of a bad solenoid. All battery cables are size 00. I hate to rebuild the starter when the only actions I have made were to play with the connections. Diagnosis and recommended repair requested.