i took apart my block crank and mains yeasterday (jdm b16a 2gen) and found the following
there on 3 of the main bearings
when you pass your nail over it you can feel the grooves
im pretty sure im going to have to change these but i checked the crank and there doesnt seem to be any scrathes on it
the rod bearings are fine
thoughts

 

that's a good sign, the bearings did what they're supposed to do. Looks like a metal shaving or something got in there and the bearings flow over it so they don't dig into the rod (or crank). So you obviously need new bearings, but they did their job in protecting the other surfaces

 

Grab yourself a new set of bearings. And thank Mr Babbit for the mulit layer bearings we have these days with great inbedability.

 

i checked the numbers and it should be as follows (for the main bearings)
mains 1 2 3 4 5
pink yellow brown yellow pink <-- what the crank & block code represents

yellow brown brown yellow yellow <-- was in the block

anyreason why there off by this much?

 

Maybe someone switched the stock crank out, and those were the bearings that gave the correct clearance?