Can you weld a cyl head? to repair corrosion?

[RedLexus]

I recently got a mk1 Golf Gti cylinder head , solid lifter... went stripping it this evening in readiness for modding to find to my dismay....that it's corroded close to the firing ring on 1 cylinder , and close to a water gallery's edge in another spot. I had difficulty getting a solid lifter head in the first place..... wonder would it take TIG , and grinding back down? It is an aluminium head .

[Guy Croft]

I imagine those VW heads are weldable alloy. You go to work with burrs and chase out the entire corroded region plus some overlap into a clean undamaged region and clean with airline and brake cleaner, preheat thoroughly to 150 deg and Tig weld with pure aluminum rod then machine up and hope for the best! Keep oil and abrasives away during chasing-out.

I've only ever seen 2 heads that were completely unweldable zinc mag alloy, Fiat 127 Sport of Brazilian mfr and another I think Toyota. To be honest you just don't know till you start.

You do get an awful lot of slag and inclusions in most prodn heads; It bubbles up and burns as you weld and you often have to weld up 3 or 4 times to get a robsut weld. It's hard to get a very clean weld, but provided you get good penetration and it cleans up in critical areas like the fire ring it doesn't matter really, unless you want cosmetic perfection - in which case you will likely be disapppointed!

GC

[RedLexus]

Thanks Guy! I found a link too after , to the repair you did on the Vauxhall HS head that dropped a valve, ...what can I say but "Wow"!! I'll try get some pictures up of my cylinder head .

[RedLexus]

some pictures..

[Guy Croft]

Chase out only the directly affected region without overlapping for now and see how it looks/how far it goes.

G