alternator airgap revisted

Getting my primary back together after complete tranny rebuild and notice that my clearance with my rotor, alternator is so tight in one very small spot that P cant get even a 2 thou guage in there.

But I notice that the spot is were one of those yellow things on the inside of the alternator is that slightly sits proud.

Should I even worry about this?

mcns said:

Getting my primary back together after complete tranny rebuild and notice that my clearance with my rotor, alternator is so tight in one very small spot that P cant get even a 2 thou guage in there.

But I notice that the spot is were one of those yellow things on the inside of the alternator is that slightly sits proud.

Should I even worry about this?

Click to expand...

Read all of this then assess before doing anything. Easy does it. Just enough to get the job done.

What is the clearance around the rest of the stator/rotor?
Be sure the inner primary is neat and flush to the crankcase.


If you have a particular high spot inside the stator, you may be able to releave it by using a Dremel tool with a sanding drum.

Yes, you should be concerned about this. As you run, things can expand and that 2 thou turns into -2 thou which mean rubbing, friction, then decintagration.
If you have greater clearance on the other side (say 18 to 20 thou) then notice what side is tight. Pull the stator off and make very slight adjustment to the studs by twinking them in the direction of the tightness. Re-assemmble and re-check for at least 10 thou all around. Repeat as needed until the desired results are obtained.
You may have to snug the stator bolts a little to get a true reading.

In a word, yes. Don't run without the prescribed air gap all around - I forget what it is, 6 or 7 thou? - but do NOT rely on my memory, get the spec and make sure you have it, 360 degrees. This is serious stuff, as in wreck your alternator, primary parts, and maybe your crankshaft if you don't have sufficient clearance.

If you don't, search the forum. There was a recent (very recent, I think) discussion on this, and folks posted some good ideas on how to increase clearance where it was initially insufficient.

Best of luck. You'll solve this easily, but be sure you do!

Found that thread (and I guess my 6 or 7 thou was off!) here: alternator-air-gap-t6113.html?hilit=air gap