Engine mounting failed - advise please? (UPDATE)

[QD MBE]

Glad you got it sorted.  Make sure you get the receipt, just to prove what was done and when just in case it gives trouble again.

IMO I reckon they sheared due to be re-used, when used first time they permanently elongate, 2nd time they elongate more and fail.

There is a reason why VW say don't re-use.  As I say Just my opinion, loose bolts drop out.  

[vRStu]

I would agree Dave.

A new bolt is unlikely to fail, but both to fail is probably unheard of.

[Saint Steve]

As said great result..

Still think your dealers admitting full liabilty, by more or less cover the costs.. Lose bolts will shear under high torque if not tight...

On the question about bolts falling out, I thought the bolt heads are upwards.. just an observation if there were just to "fall out"?

I havent looked on my own car but the diagrapm shows otherwise?

[QD MBE]

I am not sure it was those bolts that went.  Bolts 'C' in diagram above, Bolt into a alloy mount that is bolted by 3or 4 bolts IIRC.  



The 2 holes that you can see bottom Right are the threaded holes that bolts C torque into.

The 'U shaped Gap' created by the 2 spigots is the slot that the cam belt runs through  (these spigots actually fit into holes in the cam belt cover - hence to even get the plastic cover off you have to remove the mount and the bracket), hence the need to remove the mount and this bracket when changing the cam belt.  this bracket is from a Mk4, but the principle is much the same on a MK5 IIRC.

I think it is these bolts that failed and sheared (Having seen it before over on the MK4 forum), and hence the engine dropped.

[QD MBE]

Eg this chap who had his cambelt changed 2300 miles before his bolts sheared.  He also had the unfortunate problem of the AA cracking his sump as they dragged it into the low loader.



http://uk-mkivs.net/forums/p/404518/2770180.aspx#2770180

Ray (aRd Some may know him)

those bolts you mentioned need to be changed each time a cam belt is done, most garage don't change them.   I think they're stretch bolts.   I hope it all works out for you.

Also another poster.

yes mate they are stretch bolts and need to be changed every time cambelt is done. i also found that out the hard way 5 months after purchasing car.

As I say just my considered opinion.  But very glad you are sorted.

[DaveB@Vagbremtechnic]

Theres a misconception about stretch bolts, there are stretch bolts which are aneeled (heat process) this makes them crunchy on the outside (to help roll the threads) and squidgy on the inside, theyre about 15 quid each and have special markings on them, they also stretch prior to ultimate load. Normally found in aerospace applications and connecting rods.

VW Bolts which are referred to as stretch bolts are a lower class of tensile strength which are in essence over torqued one time only, many of the suspension and subframe bolts are stretch bolts which are 8.9 class but normally get 12.9 torque settings plus a quarter turn, cheap and wont come loose - just dont reuse them

[gazbutS3]

oops my cars gonna fall apart, the subframes been off and the bolts re-used and the engine mounts too 

so when someome fits a walk kit do they fit new bolts?

[vRStu]

Gaz you'd probably be quite horrified if you realised how many of the VW bolts are 'once only'.

In answer to your question IIRC then yes they should be replaced.

[Top Cat]

oops my cars gonna fall apart, the subframes been off and the bolts re-used and the engine mounts too 

so when someome fits a walk kit do they fit new bolts?

Not going to be taking photos of your car when you are next flying round Anglesey. More risky than traveling behind JoesGTI. 

[Ands GTi]

So has he actually said what went wrong? or what failed? and why has he replaced everything required F.O.C if he says he's going too? but not admitting liability..

He said that 2 bolts had sheared off (sheared was his phrase). And that the state of them was such that they could not determine whether they were faulty or just not secured properly. So it's either a product fault (warranty) or tech error (dealer fault), so they need to sort regardless.

I will try to get to the bottom of it when we next speak, but don't think I'll get a lot more than that. They're not NOT admitting liability, he just hasn't said the words "it's our fault".

Overall much happier than I was last night though 

Hey dude. Haven't been on here for a while but caught this thread. Exactly the same issues I had. Dealer admited they hadn't changed the bolts after I said it was in the workshop manual (thanks Stu!)

Glad you got your money back.