Crankshaft stamping

[Blaze0010]

So, while the block is being bored, i was looking to choose the correct crankshaft bearings.
While i still have to correctly measure everything with the micrometer, i was hoping to getting some help from the block/crankshaft stamping.
On the block it was easy, 22222 , all good here, on the crank i can't really find a single number. Referring to the manual spots, there are no numbers.
I could check old bearings and track back for the crank numbers, but since i've removed them and i'm stupid, they are not in the correct order, so i don't know how much sense this could have.
Any suggestions?
I was thinking to order a Mark 2 set, measure the crank and measure the bearing with a bore gauge, and from that choose the correct size, and at the end, double check with plastigauge.

[Ivan141]

That's odd.. almost as if someone removed the numbers.
Personally, I would just buy some decent brand aftermarket bearings, verify clearance is in spec with some plastigauge, call it a day.
The clearance using those numbers is highly accurate (assuming everything is still in spec after 30-40 years), but the bearings cost a riculous amount from Toyota dealers.
So if you're going to be ballparking it.. go with the 40 euro/dollar set, not the $300 set. Furthermore, I dont think plastigauge is anywhere near precise enough to show up
the differences in clearance those stampings make. I will be trying to build my own old 3-rib block using off the shelf Glyco bearings for the same reasons outlined above.

[The Doctor]

I made the mistake to buy the Toyota bearings. Spend an absolute fortune. Only to find out afterwards that the difference between the Toyota bearings is minimal. I don't have the 4age manual to hand right now to check the exact numbers, but in the future I wouldn't bother with the Toyota bearings.

[Blaze0010]

That's honestly good to know, considering the missing stamping on my crank.
I'll probably go with the ACL bearing, the standard one not the Race, from Flo's, plastigauge and call it a day.
Being a very basic stock rebuild i'm probably worrying too much.
I've measure the crank and rod journal are all 40.000, while main journal goes from 47.985 to 47.990, so according to the manual, in spec. I'll just re-check to run out to be sure, but also that seems to be all good.
I might do some polishing, but honestly don't even know if it's worth it!

[oldeskewltoy]

not uncommon on 40mm rod journal cranks (no numbers).

Also... in USA it appears that 4AG bearings are going away

[Blaze0010]

Ah, that's good to know. The 4AGE manual i have refers to the smallport version with the 42mm crankshaft, so that could make sense.
I hope to never have to change bearing again, but in any case let's just hope that someone will keep producing them

[Blaze0010]

Finally got the chance of measuring the oil clearance for both main and rod bearings.
Rod bearings appears to be in specs (0.020 - 0.051 mm) with a good 0.038ish on all four.
Main crank bearings seems just a little above specs (0.015 - 0.033 mm) with measure going mainly I estimate between 0.0035 to 0.040.
I’m using ACL STD size bearings, not the racing one.
Not sure if it’s worth to have the machine shop grind them and purchase the undersize one, or if these are still good, considering i’ll mount the 20v oil pump that should have higher oil pressure, maybe with a slightly thicker oil.
Any suggestions is welcome!