The bolts that hold the engine mount on are stretch bolts. So are designed for one use only. They will fail if re-used, and cause damage. I hope they have not caused damage to the head/block due to being loose.
Not sure about that.
Quote: Just to let everyone know that I have never had an issue with re using any of those bolts. Not even VW bother with new ones.
Taken from here: http://www.mk5golfgti.co.uk/forum/index.php/topic,20317.msg284188.html#msg284188
I am not an expert but others are.
Not trying to disagree or annoy just what I have read
More likely that they wernt tightened at all tbh..
Good luck tommorow getting it sorted.
Sounds like some spanner monkey has gone for a coffee break whilst doing the O.P's car
Those are big bolts to called "stretch"bolts
they are stretch bolts, designed for one shot only.
QD .. You don't even know whether the VW tech tightened them in the 1st place, so whether they
were reused would mean they have indeed sheared off, or were just sat in the castings on the Engine mount ..
Only the O.P and tech at vw will see whats happened... i still think they wernt tighten and forgot about personally. But like you , only asuming as to whats happened...
They are a fair size bolt, they wont break under such a small ammount of torque. Its more like "good practice" to replace them.
Always makes you wonder why wheel bolts aernt replaced everytime a wheel or tyre is changed?
New bolts may well have Loctight on the threads to prevent them from rattling free, rather then a bolt breaking..