In need of a outer sill

[Perfectjake]

Just taken my (new to me) '97 Z3 in for its MOT and it's failed because of the rust on the outer sill on the driver side, they quoted £150-200 for a weld, but there is rust further up so I think just replacing the entire sill is the best thing to do. After checking eBay and a couple of breakers I cannot find one. Anyone know a guy or a site that's good for Z3 parts?

Any advice is much appreciated. Also apologies if this is in the wrong section.

 

[Antm72]

These can be brought new from bmw for less than £200 and they do bolt on better than patching it in the long run.
No one makes a pattern part i don't think it is a common problem and most go the bmw route.

 

[mrscalex]

What you see on the outside is a sill cover (the painted bit). On the inside is the sill itself which is a structure integral to the chassis with little port holes on the external face. To some extent it doesn't matter if your sill cover is rusted as it's not structural. However the sill covers tend to rot from the inside out so they are a clue that all is not well internally if rusted.

So I'm not sure why your car has failed on rotted external cladding unless they can a) see through to the structural sill and that's going or b) there is a dangerous sharp edge that could hurt someone.

You can't replace the internal structural sill. So if that's holed a) it's pretty unusual and b) you can only really weld it up.

The sill cover is a different matter and is a quick job to physically replace. You'll struggle to find a decent pre-facelift sill cover secondhand. Let alone in the right colour. And welding a patch on it is going to be ugly.

You're better off buying a new one. These guys sell OEM parts and can ship a sill cover from Germany for about £140.

http://www.genuineautoparts.com/uk/

You'll need to get it sprayed. You'll get a better economy of cost if you get both sides done and sprayed at the same time.

You should also take the opportunity to drop the jacking points on the underside of the structural sill and clean and treat any rust down the whole length with something like Por 15. No point putting a shiny sill cover over rust. You may also find when you start digging that the sill end of the front and rear arches is rusted or at least in need of a spring clean to clear the debris out that tends to cause these issues.

If you look at my thread here you will see pictures of all of this.

http://www.zroadster.net/forum/viewtopic.php?f=5&t=44270

 

[Perfectjake]

This is why I was confused, I asked him to recheck to make sure it was only the outer sill. He said inside was a bit rusted but intact and the outer sill is where the rust is a problem. I thought the outer sill was just cosmetic therefor not an MOT fail but they disagreed.

 

[Antm72]

Its only a cover the inside bit is the structual part they should know its bolt on!
@t-tony may shed some light as he's an mot tester.
He'll be along soon

 

[Perfectjake]

Thanks for your input!

 

[GazHyde]

They are not structural as they are only thin metal, the inner sill is the structural part of the chassis. We have seen inner sills rust badly (can't remember who it was who posted about it recently) and the offending section was cut out and new sections welded in from a donor car. @Brian H may remember as I think he supplied the donor sills.

It's getting incredibly difficult to find second hand sills in any usable condition due to the ends rusting away.

 

[mrscalex]

However it would be a fail if there was a flappy, sharp, dangerous bit of metal etc.

Your priority should of course be the MOT but it is a sign some attention as I outlined is likely to be required. This area is just about the only one on a Z3 that does commonly rust and ultimately could end the viable life of a car if not sorted. No idea how bad yours is. It might be way off such concerns and of course I hope it is. But the covers on my 2.2 project were pristine. I routinely took them off and found surface rust round all 4 jacking points and sill ends that were treated with Por 15 in plenty of time.

 

[Perfectjake]

I've just ordered a new sill from my local BMW dealer which is £114 + VAT, which should be here tomorrow.

I'll take the sill off either this evening or tomorrow, and have a look myself. I'll also grab some Por 15 and treat the areas underneath. I'm sure I saw a guide on here about doing maintaining under the sill.

Thanks again for all the input.

 

[t-tony]

The outer skin sill is what is described in the tester's manual as "bodywork" . It is not a structural or supporting panel to ANY testable item. Complain to the DVSA.

Tony.

 

[mrscalex]

Yes you'll find a detailed step by step on here.

And take a look at my .net project thread for some more idea of what to expect.

 

[5harp3y]

I've just ordered a new sill from my local BMW dealer which is £114 + VAT, which should be here tomorrow.

I'll take the sill off either this evening or tomorrow, and have a look myself. I'll also grab some Por 15 and treat the areas underneath. I'm sure I saw a guide on here about doing maintaining under the sill.

Thanks again for all the input.

thats a great price!

 

[Nodzed]

What you see on the outside is a sill cover (the painted bit). On the inside is the sill itself which is a structure integral to the chassis with little port holes on the external face. To some extent it doesn't matter if your sill cover is rusted as it's not structural. However the sill covers tend to rot from the inside out so they are a clue that all is not well internally if rusted.

So I'm not sure why your car has failed on rotted external cladding unless they can a) see through to the structural sill and that's going or b) there is a dangerous sharp edge that could hurt someone.

You can't replace the internal structural sill. So if that's holed a) it's pretty unusual and b) you can only really weld it up.

The sill cover is a different matter and is a quick job to physically replace. You'll struggle to find a decent pre-facelift sill cover secondhand. Let alone in the right colour. And welding a patch on it is going to be ugly.

You're better off buying a new one. These guys sell OEM parts and can ship a sill cover from Germany for about £140.

http://www.genuineautoparts.com/uk/

You'll need to get it sprayed. You'll get a better economy of cost if you get both sides done and sprayed at the same time.

You should also take the opportunity to drop the jacking points on the underside of the structural sill and clean and treat any rust down the whole length with something like Por 15. No point putting a shiny sill cover over rust. You may also find when you start digging that the sill end of the front and rear arches is rusted or at least in need of a spring clean to clear the debris out that tends to cause these issues.

If you look at my thread here you will see pictures of all of this.

http://www.zroadster.net/forum/viewtopic.php?f=5&t=44270

Just been checking out your link. What a great site

 

[Brian H]

They are not structural as they are only thin metal, the inner sill is the structural part of the chassis. We have seen inner sills rust badly (can't remember who it was who posted about it recently) and the offending section was cut out and new sections welded in from a donor car. @Brian H may remember as I think he supplied the donor sills.

It's getting incredibly difficult to find second hand sills in any usable condition due to the ends rusting away.

@PeteZ3 was the guy I posted the sills too, not heard from him for a while, hope he got it sorted.

 

[GazHyde]

Thanks Brian, managed to find the thread showing how bad it was - https://zroadster.org/threads/panels.9358/#post-139134

 

[mrscalex]

Thanks Brian, managed to find the thread showing how bad it was - https://zroadster.org/threads/panels.9358/#post-139134

Wow! Good warning about what can happen though, especially round the jacking points.

 

[PeteZ3]

Hi guys! yes! i have done mine. Brian really sorted me out with replacement Structural sills and i got my body work sills from BMW and had them sprayed.

I have been so busy recently so im pretty late to the party! hope you get your zed sorted and on the road where it belongs!

Ive just had my zed at the local BM specials today regarding a rough idle, turns out its a faulty camshaft sensor, so ill be changing that soon!

Any sill advice, PM me, Oh and @Brian H I found your return address in a draw the other day. i had full intentions of sending you a tipple for Christmas, but simply couldn't find it anywhere.... soooo.. whats your favourite summer tipple? (presuming you drink)