Cracked Block?

[Radcam]

Hey all,
I have what looks like a repaired crack in the block of my D2. This is behind the injection pump. I would have never noticed it except I was cleaning the block up after I removed the ip.

My guess is that the crack was caused by water freezing in the water jacket behind number 2 cylinder. Any other opinions as to the reason for the repair are of course welcome.

I'm not really concerned about it. After all it has been this way for at least thirty years without causing any problems.

[Old Magnet]

You are correct....freeze crack....quite common on the D2's and D4's in that location. Repairs, either welding or epoxy seem to hold up quite well. Not normally a very stressed area of the block.

[Arthropod]

Years ago I saw a picture of a crack repair that looked good. They drilled and tapped holes all around the area (a square bolt pattern), then bolted a rubber gasket and brass plate over the crack. The person said it had been repaired like that for years with no leaking.

I had a D7-17A that had a long crack in the water pump cover. I repaired it will nickel welding rod. The slow weld method where you don't let the piece get very hot, so you have to weld a little at a time. It held up nicely.

[bgates]

I've taken a cracked block and drilled a hole at each end of the crack to stop it from spreading, then heated the block, at the crack, cherry red and used a mig welder to weld it. I ground out the crack a little with a hand grinder and never had a problem. This entire procedure takes about an hour or less.
So far, I've had very good luck with cast and a mig welder. I can hardly use my stick welder anymore.

[Jack]

I bought D2 5J3691 (1941) in 1969, with a plate bolted over the hole in the water jacket. It was probably one of the reasons I got the Cat for a short song. I've never touched it. It has never leaked or caused any problem. The Cat is still in service after 40 years with me, and the plate is just black steel, probably with the gasket completely covering the face of the plate. I'm not sure, I've never messed with it.

[Radcam]

The weld looks like a high nickel rod was used. It also appears that they used a stitch technique. I'm guessing a stick welder was used.

Like I said in my op it hasn't been a problem for thirty years and I don't see it being a problem for another thirty.

[jmvmopar]

Here is my cracked D4400. What a ugly weld. But it wasn't leaking so I guess all is well.

[SJ]

Give it a paint job and it will look like nothing ever happened to it. As long as it doesn,t leak then that,s the main thing.

[bobcatd311]

bgates

Hi I assume you used acty with a welding tip to get the crack cherry red is this correct? Did you just heat the crack as opposed to the whole piece? In my case the crack is d2 pony motor block.

Also anyone if I use a stick machine with nickel rod should I preheat the crack or just weld it cold?
Thanks
bob