So my 1970, 350 4wd automatic blazer has gone through about 4 or 5 starters. It currently doesnt run because the starter on it now is out. It works for a while then the starters seem to grind then a couple days later the starter wont engage at all. I'm looking for help as to what I am doing wrong. I have taken it to a few shops and put in a couple myself but something isnt working right.

 

What does the teeth on your flywheel look like?
What do the teeth on the starter look like?
Does the solenoid engage?

 

Some GM starters require shimming to get proper mesh of gears. Check the teeth on the flex plate. You remove the starter and will have to turn engine over by harmonic balancer bolt on front of engine. Most of the time you will find 4 bad spots/ missing teeth around the circumstance of ring gear.

Misaligned Starter / Improperly shimmed.
Defective/Damaged Starter Gear
Defective/Damaged Starter Bendix.
Loose Flexplate Bolts
Trying to start the engine when it is already running.
Brad

 

I have replaced the flywheel one of the times because it was damaged, it sounds like it hasn't been in the right spot, would you know the proper way to get it the right height with the shims?

 

YouTube is your friend on this procedure.
Brad

 

How'd that work out?