I am not the only one to believe this is a good practice.

http://www.shoptalkforums.net/viewtopic.php?t=121376

And if there is the slightest possibility the brass gear could be damaged, I believe it's well worth it to remove the pinion before the flywheel is removed, and not to install it till the end play is set and the flywheel is permanately installed.

I've never found a reason to do this. The key to safely rotating the engine witout the flywheel installed is simply rotating counter clockwise.

Its difficult to damage the brass gear even with the flywheel off and a dizzy installed.

why counterclockwise?

I always have all of that in place before I measure for the shims...never gave it another thought...that doesnt mean I am right...just how I have always done it and they all seem to run fine...

Rich

Another one with 100's of T1 and T4 engines under his belt that never does this.

If I'm going to flip the engine up-side down, on a stand, I do stick a dizzy in so the drive won't fall....but that's it.

Counterclockwise puts a load on the drive pinion that keeps it in place... CCW rotation will help keep the gear seated against the shim and thats what keeps damage from occurring.

The damage only occurs when the gear is partially lifted from it's seat and the mesh of the brass gear to the pinion is interrupted, the brass gear always loses this battle. The flywheel being off introduces a shift of the crank's position and the brass gear's position as well.

I use the CCW rotation when doing assembly and test work and I have never had an issue from it.

Its just plain common sense.