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Mains Jounal Measured with micrometer what colour code is needed ?

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McCabe-Thiele (Ted):

--- Quote from: K2-K6 on April 10, 2021, 01:49:20 PM ---"Not sure how to use Plastiguage to help with identifying 1 & 5."

Likely that these two are going to be at least Brown to then check with plastigauge.

--- End quote ---

That's an interesting comment as I have completely unscientifically asigned Brown to 1 & 5 on the basis that my cranshaft main jounals are most likely to be in the range 1 of the table so using the crankcase allowance in column C that gives me Brown, as both bearings 1 & 5 are the same batch number STD D6H-A they are both Brown plus the only hint of any colour on the shell edges is rust brown!

Next question to self is what size plastigauge do I need for the clearance range of 20-46.

I am guessing I only really need to use the 8 bolts that secure the mains when checking not put back all the upper & lower crancase bolts.

K2-K6:
I was looking at it from the probability of Honda making the cases with wider tolerances on both those journals AND the crankshaft, and so making requirements for the most extreme shells.

The cases you could "possibly" see if line boring that one end could have characteristic marginal tolerance matching (depending on production method) but crank pins done individually wouldn't conform to that potential error as ground individually. 

So a machine shop guess of having crank likely to be very close to the target in those two 1&5 locations paired with the case tolerances you have, to give reasonable scenario. 

Plastigauge should be on target if that's how they turn out, but accurate mic-up of those two journal will absolutely confirm.

McCabe-Thiele (Ted):
I have bought myself a reasonably decent micrometer - I checked it against the 25 mm standard with the crank & micrometer at room temperature and have taken readings on all 5 journals.

All five main journals are measuring as 31.99 mm the Crank Case Code is C-A-A-B-A what are the corresponding colour codes here please as I can't follow the table with any confidence?

As 32 +0 -0.010 & 32 -0.01 to -0.020 appears in two columns in the tables my measurement seems a bit pig in the middle I'm thinking journal 1 that has case code C is Brown or Black.
Journals 2,3,&5 are Yellow or Green. Journal 4 is Green or Brown.

The only journal that was still showing a colour code was No 4 that was definitely Green. If the codes on the shells mean anything at all then !1 & 5 are the same  leaving 2, 3 & 4 as the same.

Advice / comments sought please. I can't see any markings on the crankshaft itself just holes where the webbs have been drilled for balancing presumably.

K2-K6:
Have you got a vernier scale on the mic to give the 3rd decimal place number?

It'll show which way the tolerance is leaning to and help make the decision easier.

Bryanj:
 I would take the smallest pin size, work out code for that and run in for 500 miles

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