I was just wondering, because I saw a pic of what it's supposed to look like w/ a bearing installed properly. There is a protruding nub that sits in the hole in the bearing.

This made me realize that when I had my main bearings replaced on the last rebuild the shop pressed out the end of the set screw along with the old bearings. I guess it was my fault for not telling them since they are not a rotary shop.

I had the motor back apart and the bearings looked fine. They had broken in nicely after 1500 miles of use... yes my motor is back apart after 1500 miles due to an unrelated problem.

I don't see the point of this set screw except for alignment. Previous motors (86-91) only have the tab and they are fine. If you need a set screw to stop the bearing from moving in it's bore, then you've already spun the bearing and are screwed... so what difference does it make?

 

I asked myself the same question a couple of weeks ago. They were a little difficult to get out because of the threadlocker, but an easy-out got them loose. Could that be why the shop overlooked them? I replaced them w/threadlocker just so there wasn't a oil-channel but couldn't figure out their purpose either.
Along those same lines, I wasn't sure of the purpose of the bearing tab, other than alignment....and costing you another bearing if you miss the tab indent.

 

I doubt they noticed it. They would have had no problem getting it out if they had. I get them to do broken bolt and stud extractions for me all the time.

I'd really like to just leave them alone since they look fine after 1500 miles of break in. If it ain't broke, don't fix it...

 

I'm too paranoid, so I'm just going to get new bearings and pins and do it the way the FSM says to do it.

I'm afraid that the remainder of the pin scraped the back of the bearing and made a high spot.

I can't justify pulling the motor again over $100 in parts and a week or two of waiting. All I have to do is take the oil pan, front cover, water pump housing, and flywheel back off. No biggie.