New Block

E

Eric Jensen

Junior Member
Started restoration on a 29 truck. The block has two cracks valve to cylinder - I’ve found a replacement used block. I’d like to move parts over to the new block. What should I be concerned with?

93387C0A-1C0F-479B-A1E1-3E8D9EEE046B.jpg
 
Last edited:
Make sure that the parts you move over are in very good condition, otherwise you will be building in problems. Best to use new parts if you can.
 
Take your replacement block to a reputable machine shop RECOMMENDED BY VETERAN MODEL A OWNERS in your area. Have them clean and magnaflux the block before you do anything. They can tell you what it will need. I have learned the hard way, not every machine shop is created equal. It’s been two years since I pulled the engine from my truck and still don’t have a buildable block yet.
 
If it's a bare block, inspect the old crank and see if it has main journal sizes that will work with the replacement block. This stuff has to have good clearances to work otherwise it will need the block babbitt reworked.
 
The odds that the salvageable parts from the cracked motor will be the same sizes of the replacement block are significantly against you. For examples: Main bearing diameter; Piston fit to cylinder bore; Valve seat sizes.
 
Blocks are everywhere, keep looking. It should not be hard to find a repairable without cracks but you will be doing a complete rebuild from there.
 

Attachments

  • IMG_8131.jpg
    IMG_8131.jpg
    32.9 KB · Views: 93
  • IMG_8218.jpg
    IMG_8218.jpg
    23.6 KB · Views: 82
  • IMG_8186.JPG
    IMG_8186.JPG
    43.3 KB · Views: 79
What causes that cracking?



my guess is heat and poor metallurgy during that time.


why the burtz new engine block will be superior.............
 
ronn said:
What causes that cracking?



my guess is heat and poor metallurgy during that time.


why the burtz new engine block will be superior.............
Click to expand...

The cracking is caused by overheating the engine as the two center exhaust seats are the hottest part and has nothing to do with "metallurgy". Do the same to the Burtz block and it will look just like these pictures shown by initial poster.
 
Modern cast iron has a bit more ductility and nodular cast iron has more strength but the old Ford engine blocks did fine unless they froze up in winter or got severely overheated in operation.
 
Maybe it could be repaired as has been suggested, but weigh the cost of repair to the cost of another block. If you get the block repaired don't forget that is still a repaired block. Model A's are not scarce exotic things. Just my two cents. :)
 
You must log in or register to reply here.
Back
Top