overheat on the highway - is my motor dead

[dahicori]

that is this very bolt indeed

And yes that is the case, I set cylinder one to TDC before disassembling the engine. Well that's a good news! I will keep you updated

[dahicori]

So it took a long time !!

But I finally removed the head.

I can see some cracks betweens the valves. but there is no others cracks around.

I am going to check for warpage now.

[dahicori]

Hell you all, does this crack look bad to you?

[v8volvo]

Those are the usual cracks that almost all of the old series VW/Audi/Volvo diesels have.

The general rule is that as long as you can't fit your fingernail into it, it is OK. That one looks pretty normal, though you should check it.

Are there any other cracks in other locations, like from a valve seat to a prechamber? Other cracks would be a problem.

And, is the head surface flat or warped? I think that would be another major thing to check after the history on your engine.

[dahicori]

thanks for this answer! Well, I can say there is no crack around, the head seems on a visual range but I still did not run the test yet. I bought a 300€ petrol 1.2 twingo (famous french car) to replace the 240 , because I broke. And of course, the HG failed on this one too
I have to work on the little car before tackling the volvo again...

I do have another question : I think I remember one cannot have a head machined with more than 0.05mm of warpage. But some people told me ...that the machinist can "ignore" the manufacturer's recommandations and flatten the surface anyway. Would you agree? I looked for a second hand head and its simply impossible to find. a brand new head is above what I can afford to have my car back on the road again...