Ok so I can attach on any of those bolts to turn it after marking it? And I can use two wrenches instead of a breaker bar? I don’t have one at the moment.
No! Don't mess with those bolts! lol
I was removing those bolts in preparations to remove the engine. That's the only pic I had of that area. Ignore the wrenches. I posted it for reference so you'd know the three bolts nearest the outer edge of the flex plate are for the torque converter-to-flex plate bolts. The bolts you need to check are the flex plate-to-crank bolts, located near the center of the flex plate. There are six of them in a tight circle. If you refer to that first pic with the cracked plate, you'll see the six shiny circles around the holes in the center. Those are the six bolt holes. They're not near the outer edge of the plate, but near the center. So, looking through the inspection hole, you'd have to look further up.
To see all the way around it, you'd need to turn the engine. To turn the engine, you put a large ratchet on that large bolt head in the center of the pulley on the FRONT of the engine.
Picture this: You're laying under the car, at the back of the engine/front of transmission, looking through the inspection hole.
Draw a mark on the flex plate. A line, a circle, a star, a happy face, a penís- doesn't matter.
Shine a bright light up in that tight gap between the converter and plate, towards those six bolts way up near the center of the plate to look for tiny hairline cracks.
Now, slide forward to the front of the engine to where the crank, serpentine belt, radiator, etc. are located.
Put a large ratchet with a 15/16" or 24mm socket on that bolt that's in the center of the crank pulley and turn it 45° to 90° or one ratchet pull or whatever you wanna make it. The exact degrees doesn't matter at all. You're just rotating it to see the parts you couldn't.
Slide back to where you were so you can look up through the inspection hole and look again for cracks. You'll notice that the penís you drew on the flex plate is no longer in that same position because the flex plate turned. All good.
Inspect for cracks.
When you've looked enough, slide back up to the front of the engine and use the ratchet to turn the engine another 45° to 90° or one ratchet pull or whatever you wanna make it.
Slide back to your inspection hole
Turn the crank, inspect, etc.
Repeat until that penís on the plate is back in view, indicating that you've turned the engine a full rotation, plus or minus a few degrees, and have inspected all around the plate for cracks.
*NOTES*
If your splash shield is in place, you can remove it to access the crank pulley from underneath. It's just four bolts. Or, you can get out from under the car and reach down from the top of the engine bay to turn the crank. I think from underneath is easier.
The engine will be easier to turn at some points and harder at others. It might start out turning easy then feel like it just locks up, maybe tries to turn backwards against you. It's not locked up and you are not damaging anything. It is just because you are on a compression stroke of one of the cylinders. Just pull harder and more steadily on the ratchet and hold for a few seconds. The compression will bleed off and it'll turn and stay where you turned it. You're not turning it much at a time, anyway.
