stripped threads, help

steve54

steve54

Member
just changed timing belt and pulleys etc, by the way its an 2002 fsi, and after trying to re-torque the engine mounting console bolts one just suddenly stopped resisting,
after removal it came out with what looked like a helli-coil,
https://audi.7zap.com/en/rdw/audi+a2/a2/2002-248/1/199-199020/part no:14,
is this normal, i guess after previous belt changes (not my ownership) the console has just given up, is this normal,
60nm +90 degrees seems excessive i only got to 80nm , please help







​

IMG_20190610_124206.jpg
 

Attachments

  • IMG_20190610_124206.jpg
    IMG_20190610_124206.jpg
    2.6 MB · Views: 211
Yep definitely helicoiled.

"60nm +90 degrees seems excessive i only got to 80nm , please help"

Have you got your torque muddled up? As if the correct torque is 60nm + 90deg you'd definitely strip it with 80Nm.

Also that doesn't look like a stretch bolt to me (although it might be) and if it isn't you don't usually do a torque plus an angle.

And if it is a stretch bolt it should be renewed as they can only be used once safely


Sent from my SM-G930F using Tapatalk
 
Halduck said:
Yep definitely helicoiled.

"60nm +90 degrees seems excessive i only got to 80nm , please help"

Have you got your torque muddled up? As if the correct torque is 60nm + 90deg you'd definitely strip it with 80Nm.

Also that doesn't look like a stretch bolt to me (although it might be) and if it isn't you don't usually do a torque plus an angle.

And if it is a stretch bolt it should be renewed as they can only be used once safely


Sent from my SM-G930F using Tapatalk
Click to expand...

The instructions say that the bolts should be renewed for refitting. 60nm + 90 deg is the correct quoted tightening specification so they must be stretch bolts. I guess if those bolts aren't stretch bolts or have already been stretched once, the + 90 deg turn will result in excessive tightening torque and so strip the threads.

regards

Andrew
 
Different viewpoint
Is the console aluminium - as to me, the pics look like the threads have been 'pulled' with the remains of the thread profile winding out with the bolt. If the theory is correct, those bits of thread would just break up without much force unlike a hardened steel helicoil which would retain most of its strength even when deformed.

A stretch bolt is normally taken past its yield point by design and if re-used, tends to neck off before the full angle is reached second time around.
It's often possible to feel a bolt 'give' while going through the 'angle' sequence.

Cheers Spike
 
From the picture I agree with @spike in that it does look more like stripped aluminium thread remains and not a helicoil. A helicoil and new bolts are the answer now.
 
You must log in or register to reply here.
Back
Top