Reading ETKA hardware #s

[Marc Swanson]

> I've been told that SS doesn't have as high a tensile strength as regular
> steel (zinc plated or otherwise). Checking
> http://www.ultimategarage.com/metric.html
> that's what he says. He mentions getting propery class 70 or better for
> automotive use, but doesn't say what the corresponds to in terms of
> grading (8.8, 10.9, 12.9). I'd consider SS, but I don't know how to
> specify them.


Use common sense.  Don't go replacing your cam or crank bolt with stainless!  
Stainless is plenty strong for most of the nuts + bolts on your Audi.  Both 
me and Huw have replaced _most_ of the hardware on our cars with SS and 
nothing has broken yet ;-)


> > > N 040 183 5   Hex nut, self locking (M14x1.5)
> > > 14mm dia, 1.5 pitch?
> >
> > yes.
>
> Now, for self-locking, aren't there different types? Ie. prevailing torque
> vs. free spinning (stolen from a web page).

Whatever that means.  The only differences in lock nuts that I have come 
across is......... 

> And also, there are
> non-metallic insert and full-metal locking nuts. Did Audi use different
> kinds in different places?


The main difference is this:  Nylock or not.

In places where heat is a problem (like near your exhaust system) you will 
want to get the kind of locknuts that have a "turned down" edge on the top.  
Effectively this turned down edge puts pressure on the bolt giving the effect 
of a lock nut while Nylocks have a stirp of nylon imbeded in the top of the 
nut that gets cut as the threads go through it.  In high temp areas the 
nylocks will _MELT_.


Hope that helps!

-Marc-
87 4ktq
88 90q