I am trying to fix a Makita corded hammer drill. It hammers but the bit does not turn. I think maybe the torque limiter Makita 134527-9 is bad. I have removed and inspected it but find no broken spring, worn teeth where the two plates mesh and no broken teeth on the helical gear on the end. How can I tell if it is really bad before spending about $150 or more for a new one. Any Ideas. THANKS