DP #24 Engine failure....

[Alan Roehrich]

Drooze,
Valve contact with a piston won't cause "peening" of a bearing, nor bluing of a crank or a rod. The valve contact came when the piston got loose from the crank. You have two instances of piston to valve contact on one piston. That tells you it was coming loose once and there was minor contact. In order to hurt a rod or a rod bearing, the contact with the valve would have to be severe enough to do massive valvetrain damage, either in one location, or spread over an area.

You had a failure in #3 rod, not in the valvetrain. Period. Either the rod bolts failed because they were either over stressed or not fully preloaded, or the rod got out of round and grabbed the crank and it failed the bolts. Bluing is one of two things, poor lubrication, or a rod bore out of round. The only other possibility, and it is rare, is a crack in the crank, which, by the way causes the journal to be out of round, and usually causes an oil pressure leak.

One other possibility is the wrist pin seizing in the piston, that will either pull the rod throw out of the crank, pull the wrist pin out of the piston, or pull the rod off of the crank. It will be obvious if the wrist pin was seized.

If you've ever seen a timing chain system work, you'll know that what you're describing is nearly impossible. Timing chains don't work that way, and harmonics won't make them work that way.

You are free to believe as you wish, the parts, money, and time belong to you and your father. I've been doing this for 30 years, and Adger has been doing this about as long as I've been alive, that makes for about 80 years of combined experience, and it looks to me like neither of us feel your explanation is plausible.