Distributor rotor issues
 

Hi all. I have a 2002 blazer 4x4 4.3l
I have put 2 new ac delco distributors in because the rotor's screw keeps coming out and jamming the rotor and spinning the mounting plate on shaft. Any ideas on how to stop this?
https://cimg9.ibsrv.net/gimg/blazerf...4d05c539ba.jpg

Put a dab of blue Loctite on the screws?

Yes I did the blue loctite

If you have them tightened correctly, I can't understand why it would throw them. How long does it take?

Are the screws not long enough? Have you checked if the threads of the distributors were cut correctly? This latter issue is unlikely but it's got to be something.

Cap n rotor were orig to dist that we bought, already on it , never touched it. 1st time 136k OE then 2nd about 2 yrs, 3rd time about 2yrs. Both AC delco from big name part store. Ran great til it died. Only did plugs n wires in between.

How do the other parts of the distributor look?
Does the rotor move up and down?
Worn gear which can cause the shaft to push up?
Internal bearing loose?
Sideways movement of the rotor/shaft?