View Full Version : tig welding cast iron engine block

08-09-2004, 05:00 PM
Can this be done? I have a 2 inch hair line crack on the outside of the engine block , this part never sees any oil, just antifreeze on the inside. Dont want to dismantle the motor just to fix a hairline crack. Any help on the easiest way to fix it, beside j b weld would be appreciated.

08-09-2004, 07:56 PM
where is the crack.if it is in a fairly accessable place go to a shop that can install tapered plugs. ken

08-09-2004, 08:08 PM
Personally I haven't had any success TIG welding cast iron although I suppose it's possible. Brazing is generally the process of choice for repairing a water jacket crack, although like dullknife said the plug method is pretty slick if you can swing it.

08-09-2004, 09:04 PM
ummm. how do you "plug" a crack :confused:

08-09-2004, 09:25 PM
Also called "pinning." A hole is drilled along the crack and reamed to a taper and tapped for a tapered cast iron plug that's installed with Loctite. Another plug is overlapped by about 50% until the length of the crack is plugged. Works well although it doesn't add any structural strength to the block. I used to see a lot of tractor blocks repaired this way when I was a John Deere mechanic.

Mike Sherman
08-10-2004, 07:19 AM
I have tig welded cast. It will require proper preheat and adequate post heat. The process puts so much heat into the cast that you cannot weld it "cold".

08-10-2004, 04:23 PM
me and my family have done LOTS of engines and that. especially with our racecar motors. brazing is the only way we have ever done it and have had no problems. good luck!

08-10-2004, 05:33 PM
you can stick weld it too !!!