Civic4Sale

well im not sure what bearing to use after the micropolish on one rod journal. The rod bearing seem to be not within spec. I was using the ACL bearings. And all of the main/rod journals are within spec except one rod journal. So I know I have to replace that rod journal with an OEM bearing. But my question is how the heck am i going to know what bearing size to use after the micropolish. Before the micropolish that particular journal seem to be within spec. After the micropolish, the journals seems to got smaller. Help?

Racintweek

plastigauge.......get some

Civic4Sale

yes i know plastigage them. Thats why i said they are not within spec. So how would i know what size am i suppose to get?

FooK

there is a guide in the chiltons manuals and such available online here in the forums, they tell you what color bearings from honda are what sizes.

get a micrometer and measure the journal size on the rods and on the crank, and buy what you need.

Racintweek

measuring the journals takes to damn long

with you old bearing measure the clearance with the plastigauge and add it to the thickness of your old bearing. subtract what the OEM clearance should be and that is what size bearing you need.

projekteg

yeah, plasitgage is fine, but he said he already plasitgaged it and it's not within spec anymore, so what do you suggest, but one set of every color bearing at the note of about 25 bucks per set, just to plastigage each one to see which one fits best? the proper way to do it is to measure the big end bore of the rod with a dial bore and measure that particular journal with a micrometer. after you do that and get the measurements, use this equation.

BC = IDBT – ODC – (2 x BT)

BC = bearing clearance
IDBT = inside diameter of bearing tunnel (housing bore)
ODC = outside diameter of crank journal
BT = bearing thickness

here is a chart for honda b series bearings, not sure what motor you have, but you may have to do some searching if you have other than a b series, because i'm not sure about those.

Blue 1.510-1.507 mm 0.0594”- 0.0593”
Black 1.507-1.504 mm 0.0593”- 0.0592”
Brown 1.504-1.501 mm 0.0592”- 0.0591”
Green 1.501-1.498 mm 0.0591”- 0.0590”
Yellow 1.498-1.495 mm 0.0590”- 0.0589”
Pink 1.495-1.492 mm 0.0589”- 0.0587”
Red 1.492-1.489 mm 0.0587”- 0.0586”

Racintweek

my way and your way achieve the same thing, yours just takes longer

projekteg

how do you figure? there's no way to plastigage a bearing that you don't have. in order to find the right bearing using plasigage, he would have to use one of each color to see what would give him the best clearance, since most people don't have one set of each size bearing laying around, that's not very feesable for most people. there's no way to plastigage a bearing that isnt' physically there nevermind, i just read your post before about using plastigage and subtracting the difference, i personally wouldn't do that. plastigage isn't accurate enough to start using it like that, it can get you by to make sure your clearances are 'ok', but it's by no means a precise measuring device

Racintweek

i suck, i didnt read your whole post.

Racintweek

when the guys in the shop do a rebuild thats how they do it, VW clearances are a little bit loose when compared to a Honda but they are usually pretty damn close to thier exact calculation and they are always in spec.