[alfa] Suspension bolt torque disaster

[Jon Pike <jhpike@xxxxxxx>]

OK,  We've somehow done it again..

Marcia and I were putting the spring pan back up, on our Spider's 
disassembled front suspension,  and after she replaced the threaded rods 
with the original bolts,  I had the job of torquing things up.

Well,  the first one started tightening,  and thinking I was perhaps 
flattening a slightly cupped washer I kept going..  and going...  Sure 
enough,  the (#*%^ thing no longer gets tighter.  Not fully appriciating 
that disaster has happened,  after all, the wrench was set to the right 
torque, (61-66 ft/lb, I set to 62) and another bolt firmed up and held 
nicely, earlier.. I tried a second bolt... the same thing happened!!

I now have the two outer (closer to the wheel) bolts of the spring pan 
with compromised threads,  and no longer loosening. 
Questions:

1.  Can I trust the other bolt to hold while I cut off the nut or bolt 
head to get the other out?  I'm assuming that both outer bolts having 
problems is a rather dangerous situation.

2.  What's the best way to get these out,  without risking a spring 
accident?

3.  Since one is the special double ended bolt that is used to attach 
the swaybar link block to the spring pan,  where can I find a 
replacement part?

4. Why the hell did this happen? Could it be my cheap torque wrench is 
way off?  I didn't clean the threads completley, can some dirt cause 
failure?  Were the nuts or bolt threads possibly damaged and ready to 
fail? Is there some thing we missed someplace about doing this job?

5.  Should one always use brand new fasteners in cases like this? 
This is very frustrating,  since after a while languishing, we were 
making good progress towards getting the car back on the road lately..  
and disturbing in that I either have a torque wrench that is very far 
off  (I torqued the mains and rod bearings with that wrench!!!!)  or the 
hardware holding the suspension together might be suspect.  Or,  it's 
something else..   I'm hoping the last.. and I'm going to go out and 
spend some real money on a GOOD torque wrench after all!

Anyone have an opinion whether a somewhat dirty bolt and nut,  with a 
large amount of force on them (spring pan force from the pan flexing a 
bit) could do something like create enough localized heat to detemper 
the threads while being tightened?  I'm guessing wildly here,  hoping 
for some understandable explanation. 
And hoping that someone else has been here,  done that,  figured out how 
to avoid it next time..

Thanks!

Jon and Marcia
77 Spider
Irvine CA
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