M20b25 Main Bearing Questions

[Not a Fed]

Hello all, I need some advice on my engine. I decided to check it over as I purchased it installed in a half finished track car I picked up a couple months ago. The previous owner said a "shop" worked on it and said it was good but after seeing some of the other work this reputable "shop" had done on the car I figured I'd check it over since I already had the engine out.

I pulled and checked the main bearings and they seem a bit worn to me but I don't really have a point of reference. I have included pictures of the two worst bearings below, all of the other ones are either as worn or less worn.





My current thinking is that these bearings are worn enough to warrant replacement and that the rod bearings (which I have not checked yet) can be assumed to be in similar shape and should also be replaced. Does this seem reasonable? Also is there a way to check if the crank is okay without taking it to a machine shop? I can't see any obvious abnormal wear on it so far so I'm hoping I can just put new bearings in and call it good.

Additionally when the previous owner had the "shop" put the engine together he had a Bimmer Heads head put on. This was done with new head bolts and presumably a new headgasket. I am 99% certain that the engine has never ran since it was put together so does anyone know if I can reuse either? I know the head bolts are torque to yield but I don't know if a heat cycle has to occur for them to actually stretch. I suppose better safe than sorry but wanted to get an opinion anyways.

Finally, any additional advice or resources would be most appreciated as this is my first time assembling an engine

Thanks!
-Your Friendly Neighborhood (not) Fed

[digger]

The pics do not load.

Normally the crank journals are a visual inspection and fingernail test after cleaning. If you are unsure whether the bearings are good or not then it is unlikely the crank is damaged (w/o seeing pics).

The head bolts (if OE/oem) are a one time use once torqued heat or not, the same with the headgasket (The fire ring is a springy seal that once unloaded never seals as well heat or not). You can be sure people have tried their luck though to save some coin though probably with mixed sucess. The head gasket was probably an el cheapo worth throwing in the bin anyway

[Not a Fed]

I reuploaded the pictures, hopefully they work now.

And good to hear about the crank, I'll take a closer look at it but upon initial inspection it seemed fine. Here is a picture of one of the journals.



Figured as much on the head gasket/bolts. Is there a real difference between the OEM BMW gaskets/bolts and the Elring ones? I've seen differing opinions online.

[digger]

The bearings are worn and should be replaced, the rod brg will likely be slightly more worn than mains. That journal looks ok but more important (more likely to show issues) are the rod journals.

i have heard that some of the VR headbolts are bent like a banana but the elring bolts should be ok but its like $30 difference to OE so not as big difference as some items. The gasket i would go with is OE BMW but only the 1.75mm is available (+0.3mm / 2.05 mm is NLA) but that is not normally an issue unless someone machine a ton off the head or block

[hasa]

I would buy new bearings, let a machinery shop polish the crank, new headgasket: Elring, Reinz, OEM, new head bolts or ARP studs. Put together and run. Rod journal is most important as digger said.