When I was in high school in 1959, I blew the center main cap off of my '51 Ford. It made an awful noise, so I shut it down immediately. After getting it up on blocks and removing the pan, I found half of the center cap still held on by one bolt. The other bolt was where it should be, but the other side of the cap was half in the pan, with the rest blown out through a 1" hole in the pan. The bearing shell was still on the crankshaft. After looking at this carefully, I pulled it apart, and surprisingly, the crank and even the bearing shell looked good. Not knowing any better, off I went to the local junkyard and collected a bunch of center main caps, On my way home, I stopped at the local parts store and got some plasti-gage. To my utter amazement, the first cap I tried fit well and the bearing checked out in spec. I even used the original bearing shell. I brazed the hole in the pan and put it back together, and it started right up and ran great, with no noises or anything. I drove the car for a couple of more years until it got so rusty, my dad had it hauled to the junkyard.
A couple of weeks later, a friend with a '52 Ford said he needed an engine, so I told him about the good runner that was in the junkyard. he went up and bought the engine and put it in his car. He ran it for another couple of years and sold it. A year after that, I bought that car off the local Chevrolet dealer's used car lot at a real good price because second gear was out. About 6 months later the engine was using a quart of oil every 50 miles or so. I pulled it apart to put rings in it, and lo and behold, there was the brazed pan from 4 years earlier. I put some used pistons and a set of rings from Sears, and drove it another year or so, when I sold it to another friend for his little brother.
I swear this is an absolutely true story. I remember that my dad told me it couldn't be fixed, but in the ignorance of youth I went ahead anyway. I think this says more about Ford's manufacturing tolerances than my mechanical skill. If you can find a cap that fits, you may be able to fix it cheaply. Oh; how did it happen? I was approaching a stop light that had just turned red and shifted into second at about 50 to "rap the pipes". With 4.11 gears, I think that was a bit much for it!
It takes a lot to kill a flathead.
