head bolt torque and block

[Henry Harris]

Austin Service Journal,  January, 1939

   

[Ruairidh Dunford]

In practical terms, following this will result in snapped or stretched fasteners, in my experience.

3/8 fastenings can better cope with 30ftlbs and I suspect this directive is an error, unfortunately.

You pays your money and you takes your chance.

[Ruairidh Dunford]

Woodrow quotes a figure of 50ftlbs for the centre main cap fasteners - when followed - I have found it results in distortion, which locks the crank solid.  35ftlbs appears to be entirely sufficient over repeated applications.

[Denis Sweeney]

Many thanks Henry.
I wonder what the failure rate was back in the day, I guess as long as the material of the studs is maintained within its elastic limit, repetitive applications should not be an issue………
However there are too many unknowns particularly with the modern materials being used on the studs and so think discretion is the order of the day, I will be restricting the torque settings in future
Many thanks for the responses been interesting

[Charles P]

Many thanks Henry.
I wonder what the failure rate was back in the day, 

I guess most garages didn't possess a torque wrench so the calibrated wrist approach outlined earlier probably saved many pulled studs

Charles

[Steve kay]

I have just checked my 2CV hand book. There is not an erratum slip indicating “ The firing order should read….”:

[Ruairidh Dunford]

Tremendous engine, Steve. Simplicity in action, fires both plugs, every stroke - is that correct?

[Alan]

It is.

[Ruairidh Dunford]

I shall now check this with several sources.

[Alan]

Don’t you believe me?