Bearing size markings?

adavis

adavis

Senior Member
I have a nice 8BA block that a gentleman is looking to purchase and I'm trying to figure out what size the main and rod bearings are. I would rather not completely tear the engine down (it is currently a short block) so I pulled the front main cap and #2 rod cap. Both bearing surfaces look good, but I can't find a stamping for size like I expected. This engine has STD pistons so is it possible the bearings are all standard too??

The main bearing is marked Ford USA-T A2.

The rod bearing is marked 1505 CAA VB with "Fm" inside a little box.

I do not see any markings of 010, 020, etc on either bearing. Any idea how to tell the size without pulling the crank?
Thanks.
 
adavis said:
I have a nice 8BA block that a gentleman is looking to purchase and I'm trying to figure out what size the main and rod bearings are. I would rather not completely tear the engine down (it is currently a short block) so I pulled the front main cap and #2 rod cap. Both bearing surfaces look good, but I can't find a stamping for size like I expected. This engine has STD pistons so is it possible the bearings are all standard too??

The main bearing is marked Ford USA-T A2.

The rod bearing is marked 1505 CAA VB with "Fm" inside a little box.

I do not see any markings of 010, 020, etc on either bearing. Any idea how to tell the size without pulling the crank?
Thanks.
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Here are some pics.....
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A from ford means STD and 2 is the type of material used in the bearing.
The other one is Federal Mogul and with no undersize markings it should be std to.
The FM part nr. is 1505CA the A should be std...a .002 should be 1505CA2
 
Thanks for the info guys. Without seeing a "normal" size stamping I wasn't sure what I was looking at. I appreciate the help.


Sorry the pictures turned out the way they did.....I can't figure out how to get them to display vertically instead of across the page.
 
adavis said:
Thanks for the info guys. Without seeing a "normal" size stamping I wasn't sure what I was looking at. I appreciate the help.


Sorry the pictures turned out the way they did.....I can't figure out how to get them to display vertically instead of across the page.
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Welcome to the club!
 
I know it's a few days late but it took me that long to find the bearing making cypher . A-2 = nickel cadmium , A-3= silver cadmium , A-5 = copper lead base A-4 = tin base , A-6 = silver alloy . All were the content of bearing composition .
A1= std
B1= .004 con rod .003 crank
C1= .008 con .010 crank
D1= .008 con .003 crank
E 1= .004 con .010 crank
All the way to X1, X3, X5
They may or may not have a dash in front of the letter - A1
 
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Some of you guys seem to be mixing early floating bearing codes with later inserts bearing codes. For the later insert bearings the A2 means a +.002 oversize bearing for use on a slightly worn or polished STD crank.
 
Barn Junk said:
Some of you guys seem to be mixing early floating bearing codes with later inserts bearing codes. For the later insert bearings the A2 means a +.002 oversize bearing for use on a slightly worn or polished STD crank.
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The alpha numeric codes are year specific fo size , but it appears the letters represent the content of the bearing . They don't seem to change at least to 1950 . I think at some point ford must of settled on a universal bearing content .
The book I took the this from is missing a few pages but it's all irrelevant , just interesting so many different bearing recipes .
 
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