Rotor spacer thickness (depth)

For those you with a stock Commando rotor spacer handy and a ruler or dial caliper, would you please post the thickness (or depth) of this piece ?

While replacing my alternator, replacing the shims first, then the spacer with the spacer's recess facing out, I find that after torquing the rotor nut to 70 ft/lbs and fitting the stator over it, the rotor is recessed by 3/16" relative to the face of the stator. I'm suspecting incorrect spacer here, hence the inquiry on dimensions.

This alternator replacement is necessitated by the old 3-phase Sparx unit destructing violently during the first ride after a shop completed an engine rebuild project. Given the significant recess of the rotor, I wonder if an incorrect (too shallow / not thick enough) spacer was used behind the rotor during reassembly. I simply kept what I found on the crankshaft, not suspecting it was too thin until the stator was mounted.

Unable to achieve an acceptable air gap, even with a recessed rotor and the 3 stator mounting holes enlarged by 3/64", I plan on removing the rotor and having 10 thou turned off of it. This would be a good time to install the proper thickness spacer behind the rotor.

Thank you for your time!
Steve at Canyon Lake, TX

It is totally normal for the rotor to be recessed in relation to the stator.

stevejovais said:

I find that after torquing the rotor nut to 70 ft/lbs and fitting the stator over it, the rotor is recessed by 3/16" relative to the face of the stator. I'm suspecting incorrect spacer here, hence the inquiry on dimensions.

Click to expand...

The rotor runs close to the ignition timing scale as it is, so the clearance between the raised rotor timing pads and timing scale should be checked before attempting to fit a wider spacer.

trying to center the rotor to the stator will have no effect on the charging. it is normal to have the rotor recessed in the stater,

I shaved about a third off of the alternator stud spacers so I got the stator much better aligned with the rotor.

Thank you for the images and commentary!