Block ident and missing numbers

[jeff74]

Are there always numbers on the block in front of the passenger side head? I can't see any evidence of any

I finished the engine disassembly this afternoon, the pistons don't have any oversize marks, I need some better tools to check for sure if it's been bored , but with a caliper it's pretty much 4.000". Wondering if the block has been ground.

3970010 block , K 7 date code? I thought it was supposed to be more digits. It's a four bolt main block.

It's been somewhat apart before .. lots of timing gear plastic teeth left in the pan..

[Lee H]

Those pad numbers & letters are usually shaved off when the block is decked.

[Warrens69GMC]

K7 is not the date code. Usually they have screw impressions where the date code is...

black one is a more modern block. Notice the flat head screw

[jeff74]

Originally Posted by Lee H

Those pad numbers & letters are usually shaved off when the block is decked.

I guess I thought it was weird that it would have been decked , but had standard pistons. Maybe not.

[jeff74]

Originally Posted by Warrens69GMC

K7 is not the date code. Usually they have screw impressions where the date code is...

Thanks , I'll have a better look when I get it cleaned up

[ghackett1]

That’s a good block if it’s in good shape.

[ghackett1]

That 010 block is a good block if it’s in good shape.

[Warrens69GMC]

Originally Posted by ghackett1

That 010 block is a good block if it’s in good shape.

36k out of a motorhome

[jeff74]

How about C 23 ? Right side of block

[Warrens69GMC]

I think that means second week in March 1973

[Accelo]

Copied from the internet;

Small Block Chevy BLOCK # 3970010
Engine Block Casting Numbers

This is probably the most common 4" bore SBC Block cast. It has been used in many different applications. Only way I know to be sure of 2 or 4 bolt mains is to pull pan.SBC BLOCK # 3970010

Engine Block Casting Numbers

This is probably the most common 4" bore SBC Block cast. It has been used in many different applications. Only way I know to be sure of 2 or 4 bolt mains is to pull pan. I have had or machined many of these and they have a good nickel and tin content. I would take as many of these as I could afford just to keep on hand.

The 010's have always been considered to be a good block to use. Your block was used probably about as much as any Chevy block ever was used from April or May 69' through 75'. It came in 2 & 4 bolt mains and was used extensively in trucks. Also in Corvette, Camaro, Chevelle, Nova, Monte Carlo's and pass. Look at your oil filter housing and see if there is an 010
020
This will tell you that the block was made with an extra 1 percent tin and 2 percent nickel content. That means it's very desirable for a performance. Block. They have a good nickel and tin content. I would take as many of these as I could afford just to keep on hand.

The 010's have always been considered to be a good block to use. Your block was used probably about as much as any Chevy block ever was used from April or May 69' through 75'. It came in 2 & 4 bolt mains and was used extensively in trucks. Also in Corvette, Camaro, Chevelle, Nova, Monte Carlo's and pass. Cars. Look at your oil filter housing and see if there is a 010 or 020 stamped there.

This will tell you that the block was made with an extra 1 percent tin and 2 percent nickel content. That means it's very desirable for a performance block.

[Steeveedee]

As for timing gear plastic, piece-work mechanics don't generally remove the pan and clear the pan and oil pick-up screen of the pieces. I've seen some pretty clogged screens. I'm guilty of it, myself. It just depends on how much of the gear teeth are missing, so it's a judgment call.

[jeff74]

Originally Posted by Warrens69GMC

I think that means second week in March 1973

Thanks

[jeff74]

Originally Posted by Steeveedee

As for timing gear plastic, piece-work mechanics don't generally remove the pan and clear the pan and oil pick-up screen of the pieces. I've seen some pretty clogged screens. I'm guilty of it, myself. It just depends on how much of the gear teeth are missing, so it's a judgment call.

The screen wasn't too bad, a few pieces were hidden in the back of it, the rest were captured in the bottom of the pan by the mat of cam material.
I don't know, but I think it sat for about 30 years, truck had 1984 plates on it.

[jeff74]

I sold that block to a guy who builds engines, he found the numbers on the bottom of the block once it was cleaned up. They were on the pad where the starter would mount on some engines, the starter was mounted to the bell housing on that one.

Was a 71 code, probably original to the truck. He hadn't seen the numbers in that location before

[ghackett1]

Originally Posted by jeff74

How about C 23 ? Right side of block

March 23 cast date