42 226 six cylinder knock

[edhd58]

Well the old gal developed a knock last fall. I decided to tear her down this spring before something terrible happened.
The knock was pretty bad when the motor was cold and almost went away as it warmed up. It was still there under acceleration.
All the "running" sounds and diagnostics was telling me and others that heard it, that I had a rod knock.
I got it torn down to pistons out today and all the rod bearing and journals all look good, and the wrist pins were smooth with no play.
However as the pics show number 5 and 6 cylinders are scored. Number 5 is the one that sounded most like rod knock. It looks more like piston skirt material has transferred to the cylinder walls. Now to get it to a machine shop to see what happens next. I just wonder what happened to cause this.
I do know the motor did get hot enough once to percolate. I found a vacuum leak at the vacuum brake connection on the intake and was told that a vacuum leak will cause one to run hot.
All the damage is on the valves side of the motor.

[edhd58]

After much looking and not being able to find what I wanted. i have what I can find, +0.040 over pistons and rings.
Cylinder walls are honed and look good, just a couple very minor scratches.
I was able to get NOS Ford pistons and rings from Barnfind08 on here.
The new piston pins were 0.0005 smaller than the old ones giving them some wobble in the connecting rods. The old pins were 0.0005 bigger than the new piston pin holes. I took the whole mess to the local speed shop and had the old pins fitted to the new pistons.
Got the rings on the pistons and found out I can't find my ring compressor. A friend should have one, he drag races and builds motor so if he isn't racing I should be able to get that tomorrow. Anyway, it's getting back together. I am just trying to make sure it's all right.
Found out from the speed shop the rods only go in one way, because they have oil squirter holes in them. Also found out the new pistons dont care which way they are installed. There is no markings for front of the engine, and the pin is centered in the piston.

[corvette8n]

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Glad you were able to get the parts, keep the picture progress coming.