[Ben M.]

So, I bought this car that came with a 455 that hadn't run in over 10 years due to a "rod knock" that it supposedly had. I cranked it over by hand when the heads were on it and it had compression on all 8 cylinders. I pulled the heads off and it appears that it was recently rebuilt before it was parked as the cylinders were in great shape with no ridge. While cranking it with no heads on it, it turns nice and smooth, and when you rock it back and forth it makes zero noise like a bad rod, and when I wiggle any of the rods they are solid as a rock on the crank. So I tore the bottom end apart today and found that of all 8 cylinders, 1 (#8) has 1 pit on it near the oil hole and another (the #1) has a few more pits as evidenced in the photo:



The crank is beautiful, no score marks or anything and it looks really clean and nice. The rest of the rods are all in great shape too and no marks or scoring, plenty of oil on them.

So, question is, would this cause a "rod knock" that someone who knows nothing about cars might call it? Or would this not be an issue at all? I'm curious if this one just has a few pits due to sitting for so long. Could I just toss another set of bearings in it and put it back together? Obviously a full tear down and polish of the crank, etc would be in order but we're on a budget here and there's no point in doing work that doesn't need to be.

The part number on the bearing is 11555 and nothing else, so I have no idea what size these bearings are.

[Half-Inch Stud]

No. Yes. Yes.

[Ben M.]

Originally Posted by Half-Inch Stud

No. Yes. Yes.

My favorite answers! Excellent.

[lust4speed]

I'm wondering if there was coolant in the oil since that is about the only thing that will pit the Babbitt material that way. Do all the bearings look about the same? Were the head gaskets okay? Maybe spend a little time eyeballing the block over to see if any cylinder looks different than the others.

[Ben M.]

Originally Posted by lust4speed

I'm wondering if there was coolant in the oil since that is about the only thing that will pit the Babbitt material that way. Do all the bearings look about the same? Were the head gaskets okay? Maybe spend a little time eyeballing the block over to see if any cylinder looks different than the others.

The guy ran straight water in the engine (and the cooling passages show it). None of the other bearings show anything similar. The head gaskets looked okay, but I don't think the guy torqued the heads down properly as it was easy to remove 1/2 the bolts and I practically had to stand on a 5' cheater pipe to get the rest off (impact gun didn't even make a dent at 90psi).

[cutlas]

Could be trash that came from the oil galleries. You said this looked like it was recently rebuilt. Had this happen to me when I did not clean the block properly after machining.
Mine looked worse than this and had to have my crank turned .010 .010 to clean up the damage.

[J.C.you]

It is a gamble throwing bearings in it without having all components checked for proper specs, rods/pistons, crank, and block.

[Ben M.]

Originally Posted by J.C.you

It is a gamble throwing bearings in it without having all components checked for proper specs, rods/pistons, crank, and block.

I understand that, but I don't feel like driving it down to LA or San Diego to have a shop work on it. There aren't any machine shops up in this area.

[geeteeohguy]

I've had Stirtz Machine in Oakland do two of my Pontiac blocks....The one in my '67 was done in '88 and is still running great 77,000 miles and 24 years later. Not sure if they're still in business, but they did good work. I did my own assembly, and the machine work and specs were spot-on.

[flat-bill]

You could spend $50 on a fair quality micrometer and check all the rod journals yourself and get an idea of what the condition is. Or get 2 micrometers and check all the crank sizes. Then you have tools and gain some experience too. Billk

[Ed Fitzgerald]

The bearings look to me as if they were subjected to water. The water droplets hit the hot crank and steam blasted the bearings. Saw this numerous times in diesel engines over the years. Do a bearing roll in and drive it. If problem persists then tear it down. I recently tore down a Case diesel engine that had spun a bearing. The tractor still had 25 lbs of oil pressure at an idle. The rod bearing was the thickness of bristle board paper and had ears on it like a main bearing. From the bearing spinning on the crank it was unbelievable how thin the bearing was. The crank looked to be scored but after cleaning with muriatic acid and 120 crocus paper much of the babbit and tin came off to reveal a somewhat uniform rod journal. Then after wrapping crank with 180 emery cloth and polishing with a rope, I then went to 240 and finished with 400. Each time dip the emery cloth in diesel as it will cut better. I used the bearing beside it with plastigage and found .002 oversize bearing would work. Put the engine back together and 40 lbs of oil pressure at an idle (warm). Tractor has been running strong for several weeks and no problems. Over the years I have heard that this is not the way a proper mechanic fixes engines. I beg to differ a real mechanic can do this and have success. When you turn the crank, I believe you are nothing more than a parts changer. From the turn of the 20th century to present how many engines got fixed this way. If an engine had to have the crank turned each and every time there wouldn't have been an engine in existance back in the 40's and 50's.