What torque for a '59 18CS cylinder head?

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What torque for a '59 18CS cylinder head?

Postby Stephen R » Tue Sep 10, 2019 5:35 pm

Is there a recommended torque for the four sleeve nuts on the long through bolts?
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Re: What torque for a '59 18CS cylinder head?

Postby John Jarrett » Tue Sep 10, 2019 7:44 pm

Please see attached.
http://archives.jampot.dk/technical/Ser ... 61_no6.pdf
Looks like 40 foot pounds.

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Re: What torque for a '59 18CS cylinder head?

Postby ajscomboman » Wed Sep 11, 2019 5:44 am

Yep 40 lbs it is if you're brave enough! I chicken out at around 35-37 and also use a head gasket rather than lapping the joint as I only run on the road and can't be bothered continually lapping in the head joint. Gets rid of the persistent weeps.

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Re: What torque for a '59 18CS cylinder head?

Postby cbranni » Wed Sep 11, 2019 9:27 am

I do the same as Rob.

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Re: What torque for a '59 18CS cylinder head?

Postby bjorn » Wed Sep 11, 2019 8:58 pm

40 ftlbs in accordance with literature was what I did previously. Going the last bit from 35 to 40 always felt like it was a bit too much. On assembling my latest engine I asked Danish G80CS specialist Carsten Kuhl what he uses: 4kgm (or about 40 Nm) was the answer, any more than this doesn't help!
He knows what he's doing, so I took the advice and torqued down to 30ftlbs. Felt more correct than the 40ftlbs I was used to. No head leaks! I don't use a gasket and very rarely (almost never) need to lap head and cylinder together.

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Re: What torque for a '59 18CS cylinder head?

Postby Stephen R » Thu Sep 12, 2019 8:53 pm

I decided on 30 lb ft too, in the end. With a copper gasket too. Firing it up tomorrow for the first time in months since a big end repair. Wish me luck!

How is the riding weather in Norway? It must be getting towards the end of the season for you I imagine.

Best wishes
Steve

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