cracked block

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Oct 16, 2006 | 04:00 PM

propane32

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Joined: Feb 2004

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From: walnut cove,nc

cracked block

sent my flathead block to have vatted and checked,they say i have couple cracks from water jacket to head bolt holes they say it might not cause a problem and then it might.... what are some of your fillings on this thanks clyde

Oct 16, 2006 | 04:10 PM

fking1

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Joined: Jul 2004

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From: Michigan

Get some Aircraft Gasket liquid from NAPA and put it on the cracked areas under and over the gasket. May solve the cracks. I have used it to stop oil leaks and it is good stuff.

Fred

Oct 16, 2006 | 06:51 PM

fifty2f1

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cracked block

These cracks sound like the typical cracks found in many flathead motors and are not considered to be a problem as a rule. I assume you had the block magnafluxed which would reveal any serious cracks with special attention paid to inspecting the crankcase area and around the webs and panrails. Just to make sure when you assemble and get ready to run the motor I would add a bottle of Irontite triple action all weather seal. This stuff was recommended to me by an old machinist that has done a lot of flatheads and he swears by it. Good luck and let us know what follows.

fifty2f1

Oct 16, 2006 | 06:58 PM

ALBUQ F-1

Fleet Owner

Joined: Jul 2004

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From: NM

It is said those cracks have a Ford part number... I'm running with one and didn't use any sealer whatsoever, no problems. As long as you can torque the head to specs, you're golden.

Oct 16, 2006 | 07:29 PM

jgurland

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Joined: Mar 2006

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From: Bethesda, Maryland

There are so many schools of thought on this topic that it's hard to know what's right. When I had my flathead rebuilt the cracks were severe enough that the machine shop would refuse to give me any warranty on the rebuild if I had them use that block. (see picture in my gallery)

In addition to some of the suggestions above, some guys will weld them, others will "pin" them.

My suggestion is to find an old-timer and have him check your specific situation and help you make a determination on how to proceed. It would be a real shame to spend time and money rebuilding that block only to have it cause problems later on.

I ended up finding a replacement block and rebuilt it because I didn't want to take the risk.

Oct 16, 2006 | 08:28 PM

F6Guy

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according to Frank Oddo's book Ford Flathead V-8 Builders Handbook "Minor cracks in the deck surface can be repaired by drilling and plugging. A crack where both ends are vivible can be fixed, but there is a practical limit. Any crack that goes into a hole where its end is not visible defies repair. If there are no more than two or three cracks in each deck surface, you can consider your block a "good un."" It is common for them to crack from a water jacket to a bolt hole, I would not worry to much about it.