Engine Main Bearings Scratches and Debris

bleedinggreen

5 Year Member
Aug 13, 2018
31
7
18
Humble, TX
Let's start with some back story...
Me and my son are rebuilding the engine out of his 89 LX. We had the block at the machine shop where the cylinders were honed and a line hone was done. They also polished the crank and honed the connecting rods. The line hone and connecting rod hone was done due to upgrading to ARP bolts in both. Anyway, we washed the block with soap and water, and cleaned all of the crankshaft oil holes with nylon brush using WD40 and then brake cleaner. We installed the camshaft and crank shaft, and began installing the pistons.

The issue...
When I was installing #2 piston, I noticed a mark on the crank journal. I wanted to have somebody look at it, so we pulled the crank to take it to the machine shop. After I lifted the crank out of the block I noticed some debris on the #1 main bearing and a scratch. I looked at all of the rest of the bearings and all but one had similar scratches. This is my first engine rebuild, so I'm looking for some advice, if you guys would be so kind.

1. Is it normal to have some debris when rebuilding?
2. Should I pull the cam and rewash the block?
3. Is it worth it to buy another set of main bearings?
 

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Is that a new bearing in the picture? If so, and there's scratches in the other new bearings, strip it all down and take the block in for a hot tank. Something caused those scratches so it's obviously not clean. Did you use an engine cleaning brush and run it through all the oil holes in the crank? Also, get a new set of bearings......they're cheap.
 
@limp we washed the block and everything going in there with detergent, water, and bottle brushes. I thought we got everything pretty good. We also went through all of the crankshaft oil passages with brushes, wd40, brake cleaner, and compressed air.
 
@limp we washed the block and everything going in there with detergent, water, and bottle brushes. I thought we got everything pretty good.
Obviously not. Spend the $100 to have it hot tanked. Sometimes there's crud imbedded in the casting pores that works it's way out and wreaks havoc. The chemicals in a hot tank bath will dissolve said crud and wash it away.
 
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I found the culprit today. The edges in a few of the crankshaft oil holes have high spots. I tested some of the old bearings on the journals where the bearings were scratched, and sure enough, it scratched them in the exact same spot. I also found curled up bearing material in one of the holes. Looked like it peeled it like a carrot. Guess I’ll be taking the crank back in to get it smoothed out.
 
I've seen way too many issues with machine shops lately. I think it has to do with the old guys retiring and the younger guys being swamped with LS after LS engines. Ford Windsor engines aren't as popular as they once were. The little tricks are slowly being forgotten. Chanferring oil feed holes should be basic knowledge though.
 
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I called a couple of engine shops and they both recommended a guy that works on only crankshafts. It's at his shop now. He's going to chamfer the oil holes and give it another polish after making sure that it's straight and the journals are not out of round. I could go back and forth with the original shop, but I'd rather just not deal with them anymore.
 
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