[SteveCarr]

Hello,

I am in the process of taking the engine apart on my 930 Turbo and thought that my experience of removing the cylinder head nuts might be useful to other people.

I soaked the nuts in WD40 first and used a good quality 10mm hex insert in a socket with a large handle and mostly this worked fine, except for two very stubburn nuts that simply would not move.

I tried tapping them on the top with a hammer (carefully) I tried heating them up and they still would not move.

Eventually the inside of the fastener got rounded off with my trying (this was an unhappy situation for me).

I tried to drill out the stud but found the metal was so hard that it was almost impossible to make any progress.

Eventually I did the following: -

I used a hacksaw blade to cut the top off the nut just above the washer. After about 45 minutes sawing this left me with a flat surface.

Then I carefully drilled two 5mm holes in the outside of the nut. I was then able to use a cold chisel to easily break the nut and hence I could remove the cylinder head.

This technique worked fine on two very stubburn nuts and I did not damage the cylinder heads at all. I plan to renew the studs in any case.

I had a similar issue with the exhaust studs, 6 came off with some WD40 and careful spanner work, 3 I used a nut splitter on and the last three 8mm allen nuts were corroded and rounded off before I even started. These three nuts were totally unaccessable so I opted to drill them off. The studs were hard but this technique worked fine and it has left me with enough stud left sticking out to remove then with some careful heating of the cyclinder head.

I hope this information is useful, if anybody has any other good tips for this type of problem then I would be pleased to hear them.

Best regards

Steve in the sunny UK!