Re: IML: cracked block

["Frederick Joslin" <fljoslin@xxxxxxxx>]

I read an article in a car magazine several years ago (probably Mopar Muscle) using this method to fix a crack in a difficult to replace cylinder head (hemi or max wedge) .

They would drill a hole, tap it and then screw in the appropriate threaded rod/bolt. The next hole is drilled along the crack to slightly overlap the previous hole so that the previous threaded rod cannot turn when the next threaded rod is inserted. This process is reperated for the length of the crack and then all is ground down. They were doing this for the combustion part of a cylinder head so it must be pretty heavy duty.  

----- Original Message -----
From: gkitterma@xxxxxxx
To: mailing-list@xxxxxxxxxxxxxxxx
Subject: Re: IML: cracked block
Date: Fri, 08 Feb 2008 09:31:09 -0500

Bill's information is right on. Be sure to read his wording carefully regarding stop drilling just beyond the end of the crack. This is standard aircraft practice as well. There are thousands of commercial and private aircraft in service, some with hundreds of stop drilled fatigue cracks, flying safely around the world.

Gary Kitterman
'56 C-73 "Babe"

-----Original Message-----
From: William Miller <abmiller@xxxxxxxxxxxx>
To: mailing-list@xxxxxxxxxxxxxxxx
Sent: Fri, 8 Feb 2008 12:23 am
Subject: IML: cracked block

Greetings All,

Cracks in cast iron can be repaired if there is enough thickness.  There is a business on line with a good web site.

Metal Locking Service Inc.  1-866.Fix Iron

Their fix is similar to what we did back in the 50's to repair cracks.  It worked for cracks in flathead valve seats.  Fix the crack, cut out for a replacement valve seat and grind for the correct angle, put it back together.

We would drill an 1/8" hole just behind the end of the crack, in good metal.  Then start drilling holes down the crack. Into each hole we drove a tapered steel pin coated with Litharge (PbO) and Glycerin.  Each hole drilled clipped the previous one, so there was a solid line of pins.  The above business taps each hole and screws  a pin into the hole.

The above fix was labor intensive but could rescue a block that could not be replaced.

Darn, I sound old when I bring something like this up.

 

Bill Miller

68 Crown 4dr HT

64 300K conv.

---

More new features than ever. Check out the new AOL Mail!

Fred Joslin