Cylinder head crack

[DamirGTI 342]

Picked up an bargain 2.0T engine (unknown history) , and upon disassembly and inspection i found crack in one of the combustion chambers , in between the valves .

 

Since the combustion chamber was all carboned up (prior to me cleaning it to inspect the crack) , makes me think it's just an "stress crack" ie. hasn't gone trough deep to the coolant galleries .

 

The crack is just on the very top , hasn't migrated down to the inlet nor exhaust pockets on either side .

 

Unsure what to do with this one , ignore the crack and use it as it is , or it needs to be welded up ??

 

[PhilNW 44]

There is usually a good reason for cracks appearing in the first place, fault in the original casting etc. 

I would weld it up before it gets any worse, repeated future cycles of heating and cooling wont be good for it.

 

I had an Astra a good while ago after a few thousand miles began losing water, after 2 visits to the dealers, faulty head casting was finally diagnosed, cost the warranty company over £2000 before it was fixed.

[SRDT 182]

2.0T heads are not really special, they have 10 exhaust manifold studs but most if not all 2.0 8v heads made after the 2.0T was introduced shoud have them (late square ports XU10J2 excluded).

What they should have is sodium filled exhaust valves, I will try to find some Citroën documents about this.

[DamirGTI 342]

I thought that only the XU10J4TE had sodium filled valves ?

 

I have two 2.0 XU10 8v heads now , one from '94 NA 405 and this one from '92 XM CT .

 

Meant to use this one as an "test mule" porting and inlet type wise .. mostly because of the inlet ports entry's which need to be reshaped if wanted to use XU9 GTi inlet on one of those as once done there's no going back , curious to see what can be done with it combine with the XU10j2 NA alu. inlet manifold .

 

D

[SRDT 182]

I'm not 100% sure but even for the 16v I had trouble finding an "official" document talking about sodium, at the very least the valves have another part number.

I'm looking at Citroën stuff but they don't even talk about the valves...

http://www.ckc.dk/pubs/MAN008930.pdf

301 for the original engine, 316 for the 150hp version.

[DamirGTI 342]

Hmm ... strange .

 

Guess weighing 2.0 NA vs 2.0 T ex. valves would reveal if the 2.0 T ones are sodium filled .

 

D