How to change the headbolts(topbolts?) on a 911 from 1975. A friend of mine is a mechanic and he says that you need to know how much power (Nm, drehmoment, torque) you have to use.

 

You will need the Doc on the release torque, but as a general thing before you start to loosen them, apply some penetrating oil well in advance of doing the work, and use a brass drift and hammer to give each of the bolts a firm and heavy"tap" before you start undoing. The "tap" tends to free any binding in the threads due to corrosion, electrolysis etc that comes from time. Be accurate with the blows but use force.
Regards Big Bob

 

thanks.
I dont understand what you mean with doc on release torque, could you explain? One bolt has broken and i have to change it, insnt there an amount of power you hav to use?

 

Hi, I was referring to the Forum's spiritual leader "The PorscheDoc" who may have a figure of how much torque it may requiree to undo a bolt after its been secured for a long time.
Regards Big Bob

 

I keep meaning to check the specs in my books at work, but keep forgetting. I will try and check the next time I am at the shop.