[rotorwrench]

If a person does some net surfing on this subject, they will find all sorts of stuff about it for Model Ts & As. Very few are exactly the same in how they attack the rebabbitting and finishing of main bearings (although they are all very close they are just not completely the same). There is not enough info out there to tell a person new to the subject on exactly how to perform this type repair due to its complexity. The info is generally incomplete in one way or another. Most folks that do it with very good results were likely an apprentice of someone else that did the work well. In other words, don't try to do this at home folks unless you visit with a few specialists in the know and watch them a few times. Even then, the results will likely not be what they should be the first time out.

I've seen differences in the way folks peen the mains in the block but most seem to have decent results as long as they don't skip this step completely. An old used block is harder to clean for the process than a nice new casting like Ford had to work with so that complicates things to some degree. Cast iron is too difficult to tin so peening is the only way to get the new babbitt to stay put whether it's a new block or an old one. The caps & rods are not near as problematic as the block. The rods are steel so they can be easliy tinned.

Line boring the mains is also a source of contention in how much a person should cut the clearance to. Ford published the specs for clearance giving the ideal size that they sought to accomplish so that can't be disputed. It wasn't .000 clearance either. I'd be relatively certain that they were shooting for something just barely over .001" with .0015" being to the upper limits. This is why they turned them with those electric motors to get the extra .0005" clearance. They would still be a little tight at those figures but they would turn. Ford did keep things to relatively tight tolerances. You can see that in the films they made. They checked everything instead of every other item or every five items. They checked them all. It didn't take that long to run the stuff through. They had multiple stations for time consuming items like this so that they could keep up with production. The Rouge had a well equipped machine shop that was always being improved. They certainly didn't let to much get by them. The problem engines went back to a separate repair shop where they were torn down and evaluated for repair. If they could easily be repaired then they were, if not, the parts were sent back to the foundry and used for another charge in the smelters. A person could be relatively sure that someone would check and find out why problems were happening on the line so as to find a way to minimize those problems. To build a million engines per year was quite a feat. If problems got much over 5% of production then something was wrong with the system. Charlie Sorensen eluded in his memoir that things rarely ever got that bad. The exceptions were for short periods when they were setting up for a new product but that is to be expected with any new product line.

Some of the information I've found shows folks turning the cranks in the blocks after initial machining with set ups to do that. Others just run them in on a completed engine run up stand but for the most part, the engine will turn over with the starter so you know there is some clearance. Some information out there is utter crap but you have to get familiar with the procedures to even know what is good info and what is crap. I would say that Ron's machine shop has an issue that the young fellow needs to work on there. 99% of his work could be completely fine with no defects but there seems to be problem there that he needs to look into. Any business can have problems, it just depends on what they do about it as to whether there will be any damage to a reputation. We need younger guys in this business but they need to gain their own reputation and keep it good. Knowledge comes from experience that can be both good and bad. No one needs their problems aired on You-Tube. That's just a nightmare. I'm surprised the young fellow with Hagerty didn't do more research on the subject before starting that whole mess. It certainly doesn't help him any either.