I recieved the call from the machine shop I go to,Sent in my diassembled 400 block,heads and crankshaft in and got the call the block is cracked on Thursday.They magnafluxed it and found a huge crack in the lifter valley from the front to the back of the block.I was advised not to have it welded up.They are looking for another 400 block which is getting hard to find.I have a world products 400 block I bought out of an auction a year ago.This world products engine block is brand new never used.A friend of mine wants to weld this block up.I don't trust the block and I seen the crack.It is going in my 1985 Blazer I pulled it out of.Reason for pulling it was it has 50 PSI for compression in one cylinder and it smoked.Found bad piston rings in #3 cylinder which had the lowest compression.The heads are good,magnafluxed and no cracks found.Crankshaft is still in specs.
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
Recieved the call
- Thread starter haileyj
- Start date
I wouldn't weld an iron engine block if I was in your shoes. Especially if you already have a new one.
79rustyk10
3/4 ton status
This. 400s might be getting harder to find, but they're not anything really rare or special to the point of trying to fix it. I'd use the new one since you have it, it's most likely superior in every way, anyway.
That is what I did get the new block out and bolted it on my engine stand.Washed the cylinders down with hot soap water including outside the block.I am going to keep the old block as a mach up block for later projects.I need a mach up block anyway,keep on borrowing friend's Chevy mach up block.Even painted the new block,the Chevy Orange color.
Good stuff! 7 more posts and you can show us some pictures 
Where in mi?
Oh good deal. Get that motor built and get it to the dunes!
A few of us are just over in the muskegon area
This will be a daily driver.Dad had a 1973 Blazer and he took me out on rides with,sold it when I was 3 years old.Regrets selling it to this day.I used a rethreading tap and die set to clean the bolt holes out.Was taught never to use a regular tap and die set to clean out bolt holes by my father.
I'm up near Cedar Springs and work in GR, so we must be neighbors. You've probably seen my K5 around - it's the one covered in a foot of snow hidden behind my garage out in the boonies that hasn't been driven in a month.
