So I’m looking for a engine block. As I gander around I see some that are complete motors and some that are machined blocks that never made it into a project and some that look like they have been sitting in somebody’s yard uncovered for 20years. My question is what are some of the things you check or measure to verify if a block is good? Also If a block is all rusty I understand it can be machined but how can I tell if the piti g is to deep? I have tried to search this but can’t really come up with what I’m looking for.
CK5
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Used blocks…what to look for!!
- Thread starter mark84k5
- Start date
So pass on any block that has been apart outside for any amount of time. If a block has been stored inside, pref in plastic bag, light surface rust on the cylinders is ok.
You want to check for a ridge in the top of the cylinder. The ridge is formed by cylinder wear from rings. A large deep ridge means a lot of wear.
If the pistons are still in the block check the top for a stamp, example .030 this indicates the block has bored .030" over standard. .060" is max for most engines. SBC 400 I wouldn't trust over .030".
look at the area the timing cover covers for 010 over a 020 this indicate a higher tin and nickel content, more desirable.
Inspect all the lifter boss for wear and damage, slip a lifer ,and rotate into each 1. inspect the main journals and caps. If the cap are missing they can be replaced, at extra cost and machine work. Also inspect all of the threaded bolt holes the are many but if the threads are bad on more than 1 you might want to pass.
These are steps I would take when looking at unknown block I was thinking of buying. After purchase and thorough cleaning I would be mic'ing every thing
I am curious why you are looking for a block, as opposed to a complete short block, new or used ?
You want to check for a ridge in the top of the cylinder. The ridge is formed by cylinder wear from rings. A large deep ridge means a lot of wear.
If the pistons are still in the block check the top for a stamp, example .030 this indicates the block has bored .030" over standard. .060" is max for most engines. SBC 400 I wouldn't trust over .030".
look at the area the timing cover covers for 010 over a 020 this indicate a higher tin and nickel content, more desirable.
Inspect all the lifter boss for wear and damage, slip a lifer ,and rotate into each 1. inspect the main journals and caps. If the cap are missing they can be replaced, at extra cost and machine work. Also inspect all of the threaded bolt holes the are many but if the threads are bad on more than 1 you might want to pass.
These are steps I would take when looking at unknown block I was thinking of buying. After purchase and thorough cleaning I would be mic'ing every thing
I am curious why you are looking for a block, as opposed to a complete short block, new or used ?
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i dont trust anyones word on used engines or trans .
i would buy a running engine i here run first and rebuild that over a used ? ? ? block .
if you go used get it checked at the machine shop ASAP and if bad hope you get your money back .
i would buy a running engine i here run first and rebuild that over a used ? ? ? block .
if you go used get it checked at the machine shop ASAP and if bad hope you get your money back .
I’m looking for another 400sbc. I like the one I have in my k5 and would like one for my k10. Especially because it originally came with one I thought it would be cool to put one back in. I’m not trying to do a full resto I just thought it would be cool.
So then how do you source bare blocks? Do you only buy crate motors? Or aftermarket blocks?
on the sbc 400 you'll want to inspect the water jackets and look for heavy rust scale. The cylinders are siamesed. No coolant can go between them. IIRC the factory cast a mesh between each but after awhile that mess would rust away.
If I can’t find a decent block I have some other options. I may just build a stroked 350 or I have a 350rocket out of a 73’ delta 88. From what I have heard olds motors are more expensive to build but it holds some sentimental value to it as it came from my grand fathers car that he passed down to me. The car was completely rotted out but the motor only has 68,000 on it.
