I have an '87 IROC with a 406 ci sbc. It has a brand new Optima battery, new starter cable, new Powermastet Master torque starter, and a new 168 tooth flexplate. My problem is that once in a while, when i go to start it, the starter just clicks. i can turn the key 50 times and it will just click. From underneath the car, a starter gear tooth will hit a flexpate tooth, and will not engage. I simply use a 5/8 ratchet to turn the motor over, and that helps it start mpst of the time. It also seems to work better when the battery has a jump. I've tried shimming it up and down, and even grinding the starter gear's teeth to help it catch, but nothing seems to cure it. i was curious as to why this occuring, if anyone else had this problem, and if there's anything I can do about it? like i said, 7/10 times it works on the first try, and the other 3/10 it just doesn't catch. It's a very annoying problem, and i'd appreciate any help!

 

Try to get a real-time voltage reading from the purple solenoid wire when this is happening. I'm guessing you have a voltage drop across the various connections in the start circuit. When that problem bit me (with significant contribution from the Megashifter neutral safety microswitch), I used the purple wire to energize a dedicated 30 amp relay that provided battery power to the solenoid - never had another problem.

 

I had a flexplate (new) on my Nova that was warped causing it to skip on the teeth in certain spots. Had it on engine stand to rotate it around to see what was going on. Clearance good in some spots and it would move teeth away from starter in others. New TCI plate and Proform starter (only one available at local parts store) and verified clearances all away around. Had good luck since.