Confused about Toyota Bearings?

[Lextreme II]

I got lots of pm and email about Main and Rod bearings. When manufacture make cranks not all journals are the same size. It might be .0001" to .0005" off. Instead of trying to regrind the crank to be exactly the same size. Most companies would use different bearings to compensate for the differences. I hope this thread will solve some of the confusion.

ROD BEARING:
If using a standard bearing, replace with one having
the same number. If the number of the bearing cannot be determined,
select the correct bearing by adding together the
numbers imprinted on the connecting rod cap and crankshaft,
then selecting the bearing with the same number as the
total. There are six sizes of standard bearings, marked ”2”,
”3”, ”4”, ”5”,”6” and ”7” accordingly.
Please see the first diagram:
(Reference)
Connecting rod big end inside diameter:
Mark ”1” 55.000–55.006 mm
(2.1654–2.1656 in.)
Mark ”2” 55.006–55.012 mm
(2.1656–2.1658 in.)
Mark ”3” 55.012–55.018 mm
(2.1658–2.1661 in.)
Mark ”4” 55.018–55.024 mm
(2.1661–2.1663 in.)
Crankshaft crank pin diameter:
Mark ”1” 51.994–52.000 mm
(2.0470–2.0472 in.)
Mark ”2” 51.988–51.994 mm
(2.0468–2.0470 in.)
Mark ”3” 51.982–51.988 mm
(2.0465–2.0468 in.)
Standard sized bearing center wall thickness:
Mark ”2” 1.484–1.487 mm
(0.0584–0.0585 in.)
Mark ”3” 1.487–1.490 mm
(0.0585–0.0587 in.)
Mark ”4” 1.490–1.493 mm
(0.0587–0.0588 in.)
Mark ”5” 1.493–1.496 mm
(0.0588–0.0589 in.)
Mark ”6” 1.496–1.499 mm
(0.0589–0.0590 in.)
Mark ”7” 1.499–1.502 mm
(0.0590–0.0591 in.)

MAIN BEARINGS:
EXAMPLE: Cylinder block ”06” (A) + Crankshaft ”08” (B) = Total number 14 (Use bearing ”3”)
Please see the first diagram:
Cylinder block main journal bore diameter (A):
Mark ”00” 72.000 mm (2.8346 in.)
Mark ”01” 72.001 mm (2.8347 in.)
Mark ”02” 72.002 mm (2.8347 in.)
Mark ”03” 72.003 mm (2.8348 in.)
Mark ”04” 72.004 mm (2.8348 in.)
Mark ”05” 72.005 mm (2.8348 in.)
Mark ”06” 72.006 mm (2.8349 in.)
Mark ”07” 72.007 mm (2.8349 in.)
Mark ”08” 72.008 mm (2.8350 in.)
Mark ”09” 72.009 mm (2.8350 in.)
Mark ”10” 72.010 mm (2.8350 in.)
Mark ”11” 72.011 mm (2.8351 in.)
Mark ”12” 72.012 mm (2.8351 in.)
Mark ”13” 72.013 mm (2.8352 in.)
Mark ”14” 72.014 mm (2.8352 in.)
Mark ”15” 72.015 mm (2.8352 in.)
Mark ”16” 72.016 mm (2.8353 in.)
Crankshaft main journal diameter (B):
Mark ”00” 67.000 mm (2.6378 in.)
Mark ”01” 66.999 mm (2.6378 in.)
Mark ”02” 66.998 mm (2.6377 in.)
Mark ”03” 66.997 mm (2.6377 in.)
Mark ”04” 66.996 mm (2.6376 in.)
Mark ”05” 66.995 mm (2.6376 in.)
Mark ”06” 66.994 mm (2.6376 in.)
Mark ”07” 66.993 mm (2.6375 in.)
Mark ”08” 66.992 mm (2.6375 in.)
Mark ”09” 66.991 mm (2.6374 in.)
Mark ”10” 66.990 mm (2.6374 in.)
Mark ”11” 66.989 mm (2.6374 in.)
Mark ”12” 66.988 mm (2.6373 in.)
Standard sized bearing center wall thickness:
Mark ”1” 2.486–2.489 mm
(0.0979–0.0980 in.)
Mark ”2” 2.489–2.492 mm
(0.0980–0.0981 in.)
Mark ”3” 2.492–2.495 mm
(0.0981–0.0982 in.)
Mark ”4” 2.495–2.498 mm
(0.0982–0.0983 in.)
Mark ”5” 2.498–2.501 mm
(0.0983–0.0985 in.)

 

[SCV8]

Wow, some of those size variations don't change a std. dimension even when carried out to four decimal places; that a tight number!

Good sticky, or tech article info. imo.

 

[Toysrme]

Great info! It's kinda like rod bearing caps ya know. They ile-bore the heads & caps at the same time, so no 2 are absolutely 100% the same - not that it really matters!

 

[Red Supra]

Don't forget that you can mix bearing shells to zero in your desired clearance.