Bought a Z3 - it failed MOT - advice needed!

That is so helpful!

I am quite a long way from you unfortunately, but do appreciate the offer.

I am feeling this might be worth a little exploration to get the bits off etc and then Amy e just send to a welder to patch.
Nothing ventured etc!
 
  • Like
Reactions: RB2
You get that where nobody wants to undo those 'bolts of death' because they're afraid they'll snap.

Mine looked bad too but with the outer sills off it was clear to see the back end of the thread which was quite clean. Applied some WD40. Left it soaking overnight. Next day got a torx bit a hammered it into the hole and turned. One side came out quite easy. The other side it rounded off so I used an extractor which made light work of it.
 
Duncodin said:
You get that where nobody wants to undo those 'bolts of death' because they're afraid they'll snap.

Mine looked bad too but with the outer sills off it was clear to see the back end of the thread which was quite clean. Applied some WD40. Left it soaking overnight. Next day got a torx bit a hammered it into the hole and turned. One side came out quite easy. The other side it rounded off so I used an extractor which made light work of it.
Click to expand...
I’m worried if I take the sill off it will all fall apart 🤔
 
That will not happen, and, if you don't take the outer sill off you can't possibly progress the situation.

Tony.
 
The part to be removed is just a bolt on panel that covers the actual structural sill, item 2 in the below image. It's held in place by the no 4 screws. From memory you need to take the arch liners out and the wing off which are all bolt on. Just take your time and have a box to stick thr screws in. Have a towel ready to place any painted parts onto. Tbh it's a good exercise to do to clean all the nooks of 20 plus years of grime. (Maybe just my ocd)

Screenshot_20250320_054741_Chrome.jpg


Once the panel is off you'll be left looking at the structural sill of the car. As Tony has said, you'd need to get this part on display to progress. These can often have hidden rust that can be wire brushed and treated if you catch them.

Best of luck 👍

Screenshot_20250320_054712_Chrome.jpg
 
Another one here who successfully removed those bolts after giving them a good soak in pentrant. I didn't need to use an easy-out and was able to get the correct torx bit in with a little persuasion (T40, I seem to remember)
 
Honestly I cannot believe how helpful everyone is being.

I have had a good look over the car today and apart from the MOT fail issue there are a few other little issues.

Bonnet catch does not fully secure back down, release handle does not seem to have any tension
Four way flashers came on overnight and battery flat
Drivers seat height does not adjust
Oil leak from engine

Going to get the outer sill off for a good look later.
 
Z3newbie! said:
Honestly I cannot believe how helpful everyone is being.

I have had a good look over the car today and apart from the MOT fail issue there are a few other little issues.

Bonnet catch does not fully secure back down, release handle does not seem to have any tension
Four way flashers came on overnight and battery flat
Drivers seat height does not adjust
Oil leak from engine

Going to get the outer sill off for a good look later.
Click to expand...


Bonnet catches? Easy fix. shiny new ones from BMW, doesn't take long or cost much.
4 way switch, not expensive.
Drivers seat height, take the seat out and start looking, lack of use doesn't help them, same as the bonnet catches.
Oil leak from the egine? It's a BMW, what did you expect? A good cleaning to find the leak, and then look on here to see what someone else did to fix it. 27 year old gaskets can go hard and not seal anymore, most things available from all the usual outlets.
 
I know it sounds ridiculous but a firm tap with a hammer on the seat motors is often all it takes to coax them back into life. As I understand it dust gathers in the internals and a firm shock is all it takes to dislodge it and enable a clean contacts/free movement again. (I wouldn't have believed it myself if I did not experience it first hand with my first Z3)
 
Welcome from me in Edinburgh. Where are you based
 
So tackled the dreaed sill today.

Got wheel arch liners off
Got panel with indicator off
Got kick panel off
Removed all but three bolts for the outer sill but they are stuck so trying again another day.
Lots of rust has already fallen out and there is filler around the rear off the outer sill where the hole is on the inside.

Pictures another time.
 
Best of luck your going in the right direction, hope the inner sills aren't too bad. All good advice on here, far better than the facebook site more experts on here and less numpties to contend with. Once you have any welding done ensure you paint and treat the inners a lot of people use Bilt Hamber paint then give it all a good coating of Waxoyle rust resistance covering. If your outer sills are beyond repair they are still available from BMW unpainted or you could explore using fibreglass ones that are on sale.
 
Managed to get most of the screws out of the outer sill but three are not moving so thinking of grinding the heads off them, is this a good idea.

Some of the sill broke away whilst working on it and exposed the inner sill which looks rusty but feels quite solid, I might be mistaken though.

Do I need to rmove the jacking pads as I have tried unscrewing but the screws seem to be just turning?
IMG_2915.webp
 
To remove the outer sill you don't need to remove the jacking pads. The outer sill has a cutout that slots either side of the pad.

But by the sound of it you'll need to look at the jacking points once the outer sill is off. The jacking pads have two screws holding it to the inner sill. In the inner sill is a kind of plastic rawlplug. The plug is square so shouldn't turn when you try to undo the screw. If it is turning then it possible that the plug has been pushed in to far. Or the steel around the plug has rotted.
 
Update time.

Outer sill off after a few stuck bolts ground off and it looks and feels very solid underneath.

Thinkin goff getting git up and wire brushing the area that needs welding next as it feels solid arond the hole as I did make it slightly bigger trying see how rotten it was.

I actually think this is worth progressing now!
 

Attachments

If you're going to undo those torx bolts to remove that plate then you ought to look at this bush at the same time.

Screenshot 2025-04-01 at 19.41.47.jpg


It looks shot (To me anyway)

Doing it properly is quite a big job involves dropping the whole cross member to insert new bushes. But if you search on the forum you'll see a few of us have replaced those bushes with the cross member in situ. Bit fiddly but DIY doable.
 
You must log in or register to reply here.
Back
Top