You could try welding that, but it will probably crack again.  Used Tii manifolds come up for sale once in a while, but they are usually pretty pricey.  I would replace it with a nice shorty header, it will flow the same and will use your stock downpipe.

It looks like you have the shallow Piano style pistons, so I am assuming an E12 head.  I would check the head for warpage and pressure test it.  If it passes, valve job, clean up those pistons and slap it back on.

Have fun...

Mark92131

Yes, it's an E12 head, and those are the shallow piano tops.... appreciate the advice on the shorty header, i was just looking at that one on the IE site... thanks!!

Welding cast iron is very tricky, as Mark said.  It will likely crack again. Back when I owned a weird jeep that had parts that could not be found I looked into welding cracked headers.  In the end, pre-heating, gas welding, and slow cooling seemed like too much work especially after I found a crack free header.

Zach

Hello again,

There is one on ebay right now with 2days to go. Take a look. It's not perfect, though. No BMW scrap yards in your area?

Your pistons look great. Mine had more carbon build up. I cleaned mine like was mentioned, but I read it makes no difference at all.

Remember to take a caliper and measure the head height before machining. 

All the studs look very clean!

Thanks for the tip! I'm actually leaning toward the IE shorty header right now, but will look into that. I was looking for  a post I saw a long time ago about cleaning the pistons while still in the block, but cannot find it with the search.  Do you have any tips around how to do that safely and effectively?

you would need to have it brazed. i bought a manifold from someone years ago and it came cracked.

they were nice and painted it for me which was really to hide the repair job they did that failed. anyway I had it brazed and that has held up.

Hey. As I read, cleaning isn't necessary, but that didn't stop me... 

I am afraid to describe what I did, for fear of being bombarded with critiques, but I used maroon Scotch-Brite pads. I cut them to size and sprayed just a small amount of Spray Nine on them. I was careful to not let any of the de-greaser seep into the bore by having blue shop towel handy to absorb any excess. Those pads, I read, are delicate enough for the soft aluminum. Perhaps I was most careful about not causing any harm to the cylinder walls. I made as little contact with them as possible. I followed up each piston cleaning with a careful vacuuming. 

On 1/17/2017 at 4:00 PM, Mark92131 said:

Used Tii manifolds come up for sale once in a while

Here's one...

Run4wrd, I have been reading about the scotchbrite debate as well.  I asked my mechanic what he does, and literally he uses a scotchbrite (looked red or maroon to me, pretty coarse) on an air tool. As we talked he had the most beautiful fjord 3.0CSi on the lift (yes, a CSi, not a CS), and a 1600 he was working on.  He is really about the only guy left who knows anything about tiis in the Denver area.... anyway my point is I absolutely trust him, so I think the scotchbrite thing should be fine....

Thanks for the affirmation. Much appreciated.

Looking back at the reason why I took the head off in the first place, I was trying and take care of oil leaking under the upper timing chain cover. I found out (after careful measurements with my caliper), the machinist the previous owner hired to machine the head and cover took too much material off the cover leaving it too short to seal with the bottom of the head to the block. Consequently, I had to source another cover and have it machined while attached to the head). The machinists I hired also kept the valves in the head, and rotated them as the machining proceeded. In the end, they put the valve order almost perfectly to where they should be at #1 TDC.

I ran out of time in the summer to tackle the lower timing chain cover at the same. I may have to go down there to replace those gaskets in the future. I hope I can do that without damaging the head gasket - when the time comes. First though, I need to finish the front brakes, and all things hydraulic... Time, grant me time...