Big valve head, corrosion in water ways

[Dirrt]

Hi all.

After I think I've bent the valves in Dirrt's new engine, I'm going to refit the big valve head from her old engine that had a melted piston. Naturally I have examined the head and have taken a few pictures that I'd like an opinion on please.



Corrosion on the water jacket getting close to the combustion ring, or whatever it's called. Common? Problem? This was cylinder 4.



This is cylinder 1. Same sort of issue but hard to see sorry.


Both the above bits of corrosion are on the exhaust side of the head, if that's of any use.


And after an initial soft wire brush clean up and light degreasing, here is cylinder 2, the one that had melted piston all over it. Haha. I will refit the cam, get the valves to open so I can check the ports for melted piston bits.

[Yoof]

Looks like it needs a skim Mike- valve will probably clean up (the face of it) hopefully no material has got between the valve and the guide, otherwise it might need a new set.

The corrosin on No.1 (I think) looks like it's cracked through to the combustion chamber- possability of getting it welded then skimmed, although it's a specialist job.

P.S- Sorry I didn't reply to your text, Iphone message send failure 

Pete

[Dirrt]

Haha no worries on the text yoof.

Bad news on the head front, I wanted you to say "yeah that's mint". the corrosion looks deeper than what a 0.1mm skim or similar would remove. I've examined that dark line and it doesn't appear to be a crack. I say this as I've seen an old cracked BMW head and I could see it with the naked eye. I will try and get the valves out for a further inspection.

[Robin]

corrosion looks bad however i know that my cylinder head has the same type of corrosion but a lot worse than your's. Not had any issues with mine for 5000 miles of driving (190+bhp).