Still with my recently-removed head: Two photos attached, the first of which shows how all of the water passages, except one, look with the metal gasket removed. Pretty good, I’d say, and not in need of work.
The second photo shows the one ‘other’ water passage. This is the only one with marked corrosion evident. The affected area is within the gasket pattern, but clearly corrosion has occurred. What would the consensus say on this - get it welded? Or assemble and be very diligent with my corrosion protection in future?
Typical passageway:
Yes, you are lucky that only one is corroded.
Mine were all like that one.
If it were mine I would fix that one. Clean it up as best you can, filing or grinding away all the corroded metal, then a small bead of weld should do the trick. You can hand file it down afterwards. I used a router to get mine down to .002" above the deck, then hand filed the last .002".
I didn’t do the actual welding, it was a pro at my lab who is now gone, but he probably used 4043 or 4047, maybe 5356. There is a new one out Maxal 4943 which is touted as good for Al castings.
Not knowing the composition of our heads, and the natural porosity of aluminum castings, makes it more guess work.
There are a lot of opinions on the web. Here’s one on the American Welding Society page. https://app.aws.org/forum/topic_show.pl?tid=28984
Also don’t use brake cleaner on it beforehand, it makes phosgene.
Roger, when carrying out head work on 2.4/3.4s in the day and presented with severly corroded waterways
the head was planed and a 2.8 XJ head gasket employed, depending on the gasket maker, this
sometimes worked on 3.8s also. If you do not want to get involed with welding pehaps worth considering.
Using inhibiter yours should not corrode further.
Peter B.
