Repairing broken undertray fixing stud

[IvorZ3]

Hi,

I have a really good condition z3, but one stud used for fixing the front wheel arch liner to the rear has rusted and sheared off.

Is there any way of buying and attaching a new stud, I think if i drill it, it will go through the car floor into the cab.

Thanks for any help.

 

[Pingu]

Grind it flat, drill a hole, paint inside of hole and use an M6 riv-nut and a 10mm A/F M6 bolt.

That's my go-to solution for these. I have quite a few on my cars.

 

[DomiMik]

You can order these pop rivets from Volkswagen, part number N90716103. Be careful when drilling a hole, there are several wires attached to the chassis floor from the inside.

 

[IvorZ3]

Thanks very much for the replies, both very helpful......much appreciated.

 

[Althulas]

I did the same as Pingu except I loctited some stainless steel threaded bar instead of using a bolt which in hindsight would be easier.

 

[IvorZ3]

I did the same as Pingu except I loctited some stainless steel threaded bar instead of using a bolt which in hindsight would be easier.

I'm looking at your rebuild thread....amazing amount of work you did and very useful to read....I see your studs went in exactly the same place as mine, the one towards the outer edge/sill....I expect this is more exposed in some way....my inner one was perfect, the outer rusted. If i drill this area does it go straight through into the main cab or is there some kind of box section / void behind? Thanks

 

[IvorZ3]

You can order these pop rivets from Volkswagen, part number N90716103. Be careful when drilling a hole, there are several wires attached to the chassis floor from the inside.
View attachment 318595

Do you know if i would need a special tool for these or does a standard pop rivet gun work? Thanks

 

[Pingu]

Do you know if i would need a special tool for these or does a standard pop rivet gun work? Thanks

If you are talking about riv-nuts, the tool is a converted and stronger pop-rivet gun.

When you buy one, you need to consider the access you will have, and the maximum riv-nut size.

I have one that looks like a normal pop-rivetter. I need access at 90° to the job to uses the tool, and the biggest riv-nut that I can fit is M6. You need to be able to crush the riv-nut, and my tool crushes the nut by squeezing my grip.

In hindsight, the one that looks like a pair of shears would be better, but couldn't be used in a confined space.

Horses for courses .

 

[DomiMik]

Do you know if i would need a special tool for these or does a standard pop rivet gun work? Thanks

A standard pop rivet gun will do the trick. I used some undercarriage sealant on the hole and cut off a few mm from the thread so the length is identical to the original stud.

 

[IanA]

Not cheap!!!

Pardon our interruption...

 

[DomiMik]

Not cheap!!!

Pardon our interruption...

Ebay scam, that's why I wrote that these rivets should be ordered directly from VW. Should cost less than half of the eBay price.