Explorer Engine Assembly Rod Bearings

[TRIBUNAL]

Well I am assembling the engine finally and i got all the pistons in.
I didn't torque the rods yet, I just turned the nuts snug with the wrench
When I got to the last one, #8, turns out I put #8 in the #3 hole so I had to remove #8.
When I did I saw a surprise, the streaks seen below on the new bearings.
I tried using my finger nail to see if I could feel it, and I think it did, barely.
Maybe because it was in the wrong hole? Not sure why that would matter but I figured i would put it to the test.
Well I put #3 there in #3 and tightened it snug, not torqued.
put #8 where it belonged. rotated the assembly about 10 times, then poped off the cap to #3.
There were now streaks there as well.
Could this be because I didn't torque the caps down before I rotated it?
Could it be the machine shop didn't sand+polish the oil galleys properly?
and yes the crank and everything was clean there's no sand or grit that would have caused this as far as I could see, I have been pretty careful.

Beside what it could be do I need to replace these bearings again? Not a huge deal but pisses me off pretty good.

thanks guys

 

[TRIBUNAL]

Maybe I nicked the crank installing the piston.. gotta check it out.

 

[90sickfox]

First, find out what caused it. From the pic it doesn't look too bad.

If in doubt replace it. Did you use assembly lube on the bearings ?

 

[TRIBUNAL]

Yea I used the assembly lube.
I just poped off #3 again and used my fingers all over the crank, I don't feel anything that could of caused it, the oil galley has a rough edge but I have no way of telling if it's below the surface as it should be or if it's making contact. I guess it is possible that it had some grit but I have been real careful.. I still have to drop off my heads so I may just bring the whole damn thing down and have them look at it.
I also poped off another rod cap and it looks fine.

 

[TRIBUNAL]

So I pulled off some rod caps, all were scratched and I puled off one main cap and it is scratched as well.

 

[JD1964]

The rod bearing halves are upper and lower. Are you sure you have them all positioned correctly? Also, exactly what did you use for assembly lube? Sizing bearings is important too. For instance they make bearing that are -.001. This is for when you polish the crank down to size for perfect fit. If you have -.001 bearings on a standard size journal, that might cause the scratching.

Make sure you have the right parts in the right positions and check with plastigage for clearance.

 

[mikestang63]

who machined your crank? Normally they supply/recommend the matching crank and rod bearings, and are stamped with the size of STD or how much they are over or undersized. I dont see where you put assembly lube on the bearings, did you before rotatng the crank? Why do they all look dry? What and how much did you use? I'd get some plastigauge and meaure the clearance on some crank and rod bearings- that is done dry without any lube.

 

[RangerJoe]

I can see what looks to be the left overside of green assembly lube on them. Either that was done with near dry bearings, dirty crank/bearings, or the crank is not smooth. Was it polished by the shop?

Joe