Cracked Blocks

R

Rick Douglas

Junior Member
Is there an area that the "BA" or "Q"blocks were prone to crack?
Do these cracks become visible with the naked eye?
Are these blocks with cracks repairable ?
Thank you for your input
Rick
 
From the center inner exhaust ports up to the valve seats and sometimes all the way to the cylinder walls. These are caused by overheating and can often be repaired if they are accessible.

Pan rails from freezing. Junk block

Webbing from freezing. Junk block

Center head bolt holes to water jacket. Usually ignored.
 
Rick Douglas said:
Is there an area that the "BA" or "Q"blocks were prone to crack?
Do these cracks become visible with the naked eye?
Are these blocks with cracks repairable ?
Thank you for your input
Rick
Click to expand...

Magnaflux will find cracks in the deck surface, into cylinders, into ports. Pressure test will find cracks near pan rails, behind valve springs, and other places that are hard to reach... Both of these should be performed before investing in machine work.

The eye can sometimes spot a crack, not dependably. Look to compare texture and cleanliness of different cylinder areas, the odd one will often be the offender... Through a valve seat into a port is very common...

Karl
 
scooder said:
Often wondered why a Pan rail crack is seen as a junk block? Could anyone enlighten me?
Martin.
Click to expand...

I've often wondered this myself. There was a thread either here or the H.A.M.B. about 6 weeks ago that addressed this same thing. Someone had posted some pictures of a welded repair to a cracked block pan rail that had lasted for years. In spite of that, most were saying it can't be done. I think it would depend on the location of the crack. I wouldn't scrap a block out of hand without having a very experienced welder look at it.

Anything is possible. I had a friend several years ago that was lucky enough to come upon a '28 or '29 LaSalle roadster. The previous owner had stored it over the winter with plain water in it. There were literally chunks busted out of the block. He found someone that was able to bring it back 100%. It was expensive and involved putting tghe whole block in a furnace for several days, but it did work,
 
Mart, did a bit with welding up a pan rail crack. Using some new fangled (I think) arc rods, did it cold and used the peaning method. So it's weldable. I have a cracked pan rail block Sat around that I couldn't throw in the scrap, I've read time and time again that it's scrap, cus of the crack. I can't see a problem with fixing it. Tis only water under pressure, about 7lbs, why is it a junk block.
Am I missing something?
Martin.
 
I'm thinking that Ford blocks become labelled 'junk', because there are so many, and relatively easy to find another. Like tubman above, one of the fellows in our local Ford regional group has something a little out of the 'ordinary', a very early Pontiac. Ever try to find an early Pontiac engine? So, for one of those 'rail' cracks, down the length of a very long block, he did a weld repair. It's been several years, and entirely successful. (He works at a place where he has access to a large furnace - the block was in there for over a week, and after the repair, the block was left in there to cool with the furnace - it took days, just to cool.)
Nothing 'special' about a Ford block - it CAN be repaired - either home-brew, or by a pro - just takes a little knowledge and care. JMO
 
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