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Not fully understanding Big End Bearings & colour codes.
McCabe-Thiele (Ted):
--- Quote from: waffey on May 03, 2021, 07:21:51 AM ---Oddjob,
where would the markings be on the crank as I cant see any on mine so I 'm guessing they are faint but i do not have a clue what area they are in
--- End quote ---
I have after much looking using a LED torch beam plus some petrol as a cleaner found the markings in off white on the bottom edges of the crank webs they are as follows.
No: 1 journal is marked 1A
No: 2 journal is marked 1B
No: 3 journal is marked 1A
No: 4 jounnal is marked 1B
Tried on conrods 2 & 3 but nothing has shown up. Still awaiting my new Plastigauge delivery - Friday probably.
Oddjob you can just about read the markings in the photo below.
.crank web markings by Macabe Thiele, on Flickr
McCabe-Thiele (Ted):
--- Quote from: Oddjob on May 04, 2021, 06:19:10 PM ---Yes I can see them Ted.
I was spot on saying number 1 would be A and number 4 would be B.
I'm 99% sure the colour for 2 and 3 is green as well Ted, I'm thinking that number 2 rod is 2 and number 3 is a 3. Bryan is perfectly correct in saying that the shell markings are meaningless except yours are all the same, that means when the guy in the factory went to fit the shells he's almost certainly gone to the same box for them all, hence why the batch number is the same.
There is another way to look at it, if you fit a green in number 3 that's the thickest shell listed for a conrod marked A and number 2 is marked B and the green shell sits right in the middle of the selection choice. They used to say you could go up or down a shell size but better to go up than down.
You can check of course but I'd be happy to say fit a set of Greens if your fitting new.
--- End quote ---
I have a full set of NOS Greens on the way so I'm minded to fit them anyway - it's amazing that having advice on here plus looking at an old post from 2016 by Laverda Dave has edged me slowly in the right direction - a lot to be said for taking ones time on rebuilds.
I must have looked at my crank at least 5 or 6 times since it's been out and failed to spot any markings as I was mainly looking at the web sides & not looking hard enough or cleaning enough. Much like the Sterogram 3D pictures on the ceiling at our dentists eventually you find the dolphin in a sea of dots.lol
waffey:
Ted, apologise for jumping on your thread but looks like we are in the same place.
Oddjob, I've struggled to ID any markings on the crank except one which looks to be A1. So I'm stuck and not sure what i should do next. I have a Parkside micrometre but I'm doubting it as it reads for example 32.18 but if I read the the manual I should be looking for that extra 0 i.e. 32.018. Discussed with my friend and he question the tolerance in the manual. I cant see any real colours on the bearings either....
Anyhow, I now think I need to take the crank and conrods to a local engineering firm to get measurements then i can work out the correct bearings i.e. if the crank pin is 32.018 and the conrod allowance is 35.016 then a need a GREEN bearing?????
Nurse Julie:
Waffey. The tolerance scale in the manual is correct. Your micrometer isn't fine enough to get the correct critical readings.
K2-K6:
A micrometer with vernier scale is required for finer resolution
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https://www.wonkeedonkeetools.co.uk/micrometers/how-does-the-scale-of-a-metric-micrometer-work
Link shows it used in practice.
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