Thread: First time 454 rebuild

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I am rebuilding my first motor, the unlucky lady is a Chevy 454 from the 70s. I have the large oval heads so it isn't too bad a purchase. After removing the oil pan it is obvious that someone has been into this engine before, I'm no master mechanic but the evidence is there. I have a number of questions and will probably mess up some vocabulary, but if anybody has a little knowledge to impart, in always listening.

Certain connecting rods are noticeably a different color, a more rusty patina than their brothers. Is this an indication that these got very hot at some point, possibly an indication of bad clearences or bearings?
I pulled one and the bearing looked pretty good, smooth and not really discolored.
The rods have been marked with a stamp, most are in the corresponding positions, however the number one cylinder is marked as number 2, and number two is marked as number 8. There is an additional number 8 at the other end of the motor. Were these likely salvaged from a donor motor? I was under the impression that they are absolutely not interchangeable. Could this be a reason that they overheated?

As I stated this is my first full build, I've been a shade tree mechanic for a number of years, mostly out of necessity(driving old junk cars) and I always enjoy it. I'm trying not to spend a fortune, but I also understand that good products, and good performance come with a price.

Looking forward to any responses.

Most engines, their rods are right and left sided. They are exchangeable so long as they are kept as such. Sounds like someone knew what they were doing, pieced it together.

Even then wouldn't a 2 being in the 1 cylinder be wrong? Wouldn't that be a left rod where a right belongs?

Depends on the engine. Usually there is offset for positioning the piston but the specific design varies. Simply put, if it operated without interference, then it's probably fine.

Re reading my post: I think I stated it poorly. It's not so much that a rod is for the left or right side, but they have an offset which must be positioned relative to the rod next to it. Once assembled on the pistons, you then have a set of "lefties", and a set of "righties". Also, most pistons have an offset, usually with a dimple to indicate position relative to the front of the engine.

And there have been some engines designed with perfectly symmetrical rods and pistons.

Rod big end has chanfer on one side to fit against radius side of crankthrow ------wrist pin offset and/or valve notch locations do complicate proper mounting of pistons to rods so as to have a complete set of 8 properly configured

I'm not certain if it operated correctly as it hasn't run in many years. I'll check to see if the chamfers line up correctly, and I'll be marking them correctly to prevent future confusion. I was wondering if the last mechanic maybe marked them on accident, then just made note of their mistake.

Any ideas about the discoloration on a couple of the rods while the rest are uniform? This isn't a great picture, but two of then are more of a rusty color.

Thanks for the input guys, I'm sure I'll be supplying plenty more questions as this job progresses.

Originally Posted by DennyW

Don't forget squirt holes...

All over it, I might be stupid, but I ain't no dummy.

I honestly expect the mid colored rods are result of parts swapping on a previous build.