Powerhouse starter sudden disengagement???
 

Checking to see if anyone has run into this problem. I have a POWERMASTER starter on my 572 as it turns over the starter will disengage on its own then try and reengage making one hell of a grinding noise , It doesn't matter if it's hot or cold it will still do it. Gotta figure it out I don't want to chew up the flywheel.

I'd check the starter gear engagement depth. You can pry it out manually and see how much overlap there is. There is a spec for it which GM or your starter manufacturer should have. I'd also check there tooth mesh to see if the starter needs shimmed.

put a meter on it and see if its dropping power and reapplying causing the issue.

For what it's worth, I run the PowerMaster starter 9426 on my 572ci first gen Camaro. We have had no problems like what you described. We did remove the starters' axial shim that came installed out of the box. The axial shim was preventing the starter gear to engage the flexplate teeth properly. With shim removed, my gear now engages about 80% axially into the flexplate. It works perfectly like this. We also verified proper radial gear clearance and found good mesh without adding shims.
One final thought, we used the 9426 starter which allows all three starter bolt locations to be utilized instead of just two. Your 572 block should have all three tapped holes for this which provides a really good stable mount. And make sure to use knurled bolts from GM or equivalent to prevent starter movement.
Does this help?

I'd be checking the ignition switch so see if it's dropping power -- a lot of these replacement ignition switches are junk from China..... and or a bad or loose connection. My guess is a junky ignition switch.

Also check the connections at the neutral safety switch.

I'd also make sure you have a nice big (match the battery cable size) GROUND from the motor to the chassis..... So you don't have a voltage drop issue.

The "bendix" could be going south on the starter....

And yes -- you will be replacing the flywheel after this happens a few times so it's a problem that needs sorting out in short order.

[QUOTE=GregWeld;662307]I'd be checking the ignition switch so see if it's dropping power -- a lot of these replacement ignition switches are junk from China..... and or a bad or loose connection. My guess is a junky ignition switch.

Also check the connections at the neutral safety switch.

I'd also make sure you have a nice big (match the battery cable size) GROUND from the motor to the chassis..... So you don't have a voltage drop issue.

The "bendix" could be going south on the starter....

And yes -- you will be replacing the flywheel after this happens a few times so it's a problem that needs sorting out in short order.[/QUO.

We did a voltage drop that was good Greg . I have no key ignition I run Rodgers switches they all checked out . But we did discover that we had two bent starter bolts once I replaced them and put the third bolt in it seems to have cured the problem. Great idea on the axial shim I did notice what your talking about I'm going to do that. Also check what you were talking about Todd that was good also. On to the next problem !!!

Not to make light of it... I hope you're not getting frustrated. You know this is just normal hotrod stuff that happens. Sorting out a few gremlins is just you two getting to know each other a little better...


Jeff-

Exactly ‼️ I figured I would have some sorting out to do. Now onto the fuel injection.:G-Dub:

Wait!

After all the money you spent and years of building --- and you have to work on the EFI?? Get the F outta here.....

Did I ever tell ya about all my "pro" built cars??

Yep !!! I'm a tad bit disappointed in a few things that have come up with the car. The list is starting to get a bit long but nothing major. The EFI I'm hoping is just going to be a tuning issue that will have to go back to Mike Norris will see.