Slipping hook/timing gear help

[Icho]

Good day everyone. I got my bobbin and servo motor. Went thru and checked all of the specs in the service manual. Machine was all clean and oiled so I tried it out. Made 1 stitch and that's it. It kept feeding but the hook stopped catching the needle thread. I slid the bobbin cover over and saw the timing got knocked way out. I started digging in and noticed that the hook gear slipped and was pushed back. I know it was tight. I actually replaced the 3 flat head set screws with hex head set screws so that I can make sure that I can easily tighten them. The gear is more chewed up than before so I know I have to replace it. I would love to hear any opinions on why the gear keeps moving on me before I replace it. the gear set is not cheap. Here is what I know.

-Machine is clean, moved and is moving smooth and free with the handwheel.

-timing and clearances were to service manual spec. I'm not a sewing machine tech but I am pretty good with prints, tolerances and specs. I used a Dial indicator for top, bottom, etc and an accurate digital caliper.

-The machine was crashed pretty bad and it had timing issues before I bought it. Thankfully the price reflected that.

-The hook/timing gear was chewed up. That is the proof that there was a pretty serious crash in the past.

-I hoped to be able to get some use out of it before having to replace the gear but now the gear is worse and definitely has no hope.

I am thinking the reason the gear keeps moving on me is because it doesn't mesh properly in one area causing a random meshing problem and rides up on the tooth causing it to push away and mess up the timing.

Iike I said, I will be biting the bullet and getting a new gear set but would appreciate any input just in case I am missing something because I really don't want this problem to continue with the new gear set. Sorry for such a long post and thanks for making it to the end. I added a few pics for reference. Oh and it is an Adler 269-373.