The Ford Barn

JAKEFORD · 09-20-2015, 06:01 PM

I have owned many flathead engines over the years. Some were perfect with no cracks and some had cracks. Sometimes the cracks caused problems and other times not and didn't even know about them until rebuild time came around.

The cracking I remember was mostly in the area of the valves. Seat to seat and seat to cylinder bore. Sometimes the cracking was due to coolant freezing but this should be expected if you don't keep proper strength anti-freeze in the engine.

I was under the impression that the non freezing cracks were due to some casting flaws or temperature overheating and cooling but I was never sure. I know I threw more than one block away due to excessive non repairable cracks.

Can anyone provide a better explanation?

09-20-2015, 06:01 PM	#1
JAKEFORD Senior Member Join Date: Aug 2011 Location: Eastern Pennsylvania Posts: 154	Why do Flathead V8 Blocks Crack? I have owned many flathead engines over the years. Some were perfect with no cracks and some had cracks. Sometimes the cracks caused problems and other times not and didn't even know about them until rebuild time came around. The cracking I remember was mostly in the area of the valves. Seat to seat and seat to cylinder bore. Sometimes the cracking was due to coolant freezing but this should be expected if you don't keep proper strength anti-freeze in the engine. I was under the impression that the non freezing cracks were due to some casting flaws or temperature overheating and cooling but I was never sure. I know I threw more than one block away due to excessive non repairable cracks. Can anyone provide a better explanation?