Intermittent missing

[745 turbogreasel]

A combustion leak to coolant corrodes everything in the cooling system, including the oil cooler....which you can pressure test failrly easily.

[Gizmoman]

I'm thinking sloppy weld repair of  previous foreign object damage, harder to see because the high spots have been milled.

X2 /\

I agree 100% with the above. Also, what appears to be a crack may actually be a cut from a not-so-good mill job.

[brownni]

Well fellas, I pulled it all apart and here are some initial photos.

Here is the head after wiping all the wet oil off the surface, but prior to any other cleaning:
http://sdrv.ms/1bbnSnH

Here it is after just scraping off the carbon deposits with a razor blade:
http://sdrv.ms/1bbnXHY

The crack that was circled in red in the earlier pictures of this post is here:
http://sdrv.ms/1bbob1J
http://sdrv.ms/1bbojOV

When I look into that coolant passage, you can see the crack line for a good 2mm up into that passage. Maybe that was my problem. There are also plenty of other little cracks along machine marks that look like they could cause issues for me too, but this seems like the most leaky crack since it isn't along a machine mark.

Also - sorry that these are just links. I am not clever enough to figure out how to get direct links to the image files so that the forum can display them embedded in the post.

[Gizmoman]

So what's your plan, a new or rebuild head?
I ran across this. . .
http://inlandempire.craigslist.org/ptd/4289213684.html

[TylerDurden]

Nice pix... it can really be seen how #4 is really an outlier.

The cause of the damage may be moot... bustid is bustid.

[Mark(The Miser)UK]

I'd be inclined to fill that crack somehow, as it's so fine, and should be easy to 'clog up', solder,weld etc. The head looks pretty flat  otherwise....

[745 turbogreasel]

VS. heat expansion and peak  combustion pressure, I think not.  You can get it welded it up but it will cost more than a new head.
Is that another  from 1:00 on #4 intake to the bottom of the prechamber?

[TylerDurden]

...Is that another  from 1:00 on #4 intake to the bottom of the prechamber?

If it is, that's much closer to the main oil passage that runs along the head. Still quite a way tho.

[Mark(The Miser)UK]

Anyone ever used Al MIG?

[Toby]

Yes and it would be a bad idea for repairing cracks. High deposition and low pen.

[Mark(The Miser)UK]

Yes and it would be a bad idea for repairing cracks. High deposition and low pen.

H'mm I bought a coil of it for my MIG and never got round to using it. Wasn't there a reverse polarity issue? Hard to believe a little non structural crack can't be filled. Wattle and Daub probably do it

[745 turbogreasel]

easy as
1

2

3

http://forums.tdiclub.com/showthread.php?t=175661
but unless you have a rare or special head, why?

[brownni]

What kind of tooling does one use to hold a head in place on a milling machine? It isn't as simple as just clamping it in a vice is it? What surface do you square up to when you have a semi-warped head, or a welded face?

[Dakotakid]

Brown, dude.....get your hands on a viable cylinder head....stop listening to the usual mindless dribble, and get on with your life.
Clearly the old head had the crap traumatized out of it. Box it up and ship it overseas.
Thank you.

[Mark(The Miser)UK]

What kind of tooling does one use to hold a head in place on a milling machine? It isn't as simple as just clamping it in a vice is it? What surface do you square up to when you have a semi-warped head, or a welded face?

Sand paper and 3 sheets of plate glass will do it on the kitchen table. This will machine the inconel as well.
Stick it on a banana boat to me and it will live again. 
Even silicone pressed in with a dinner knife would seal that crack