Oops! Very expensive bulb change...

[RickZ4]

As usual, after changing a light bulb, the corresponding one on the other side has gone within a month.

This time it was the front side light. As usual, rather than removing the front wheel, I just put it on full lock and went in through the wheel arch. (As usual,) getting the dust cover back in place was a bit of a struggle and I decided to reverse the wheel lock to make things easier. The wheel caught the dust cover which was 'half in' accompanied by an expensive cracking sound... Removing the dust cover was accompanied the tinkle of broken plastic :headbang:

I replaced the undamaged dust cover and surprise, surprise - after a night of rain, the lamp is all fogged up... and I have my MOT on Saturday.

My question is, what have I broken? Does the dust cover mate directly to the back of the actual headlamp unit? I can't tell by viewing through the wheel arch. Thanks for any input

 

[Ducklakeview]

You'll more than likely have broken the "lug" on the back of the lamp that the end of the cover slots under. I know BMW do a repair kit for the mounting lugs, but afaik, not for the one that holds the cover in place..

Mike

 

[RickZ4]

You'll more than likely have broken the "lug" on the back of the lamp that the end of the cover slots under. I know BMW do a repair kit for the mounting lugs, but afaik, not for the one that holds the cover in place..

Mike

Thanks, Mike. So it sounds like a new headlamp unit?

 

[Ducklakeview]

You'll more than likely have broken the "lug" on the back of the lamp that the end of the cover slots under. I know BMW do a repair kit for the mounting lugs, but afaik, not for the one that holds the cover in place..

Mike

Thanks, Mike. So it sounds like a new headlamp unit?

Depends on how badly it's broken - Please tell me you've kept the "pieces"...

Lamp needs to come out to sort, but it may plastic weld if you have the broken bits.

Failing that, what side is it, and is it halogen/xenon and pre/post facelift? I ask as I have a few parts lying around that may be useful.


Mike

 

[RickZ4]

You'll more than likely have broken the "lug" on the back of the lamp that the end of the cover slots under. I know BMW do a repair kit for the mounting lugs, but afaik, not for the one that holds the cover in place..

Mike

Thanks, Mike. So it sounds like a new headlamp unit?

Depends on how badly it's broken - Please tell me you've kept the "pieces"...

Lamp needs to come out to sort, but it may plastic weld if you have the broken bits.

Failing that, what side is it, and is it halogen/xenon and pre/post facelift? I ask as I have a few parts lying around that may be useful.


Mike

I may or may not have kept the broken piece. It fell inside and there was no way to get at it without taking the car apart.

It's the driver's side, halogen, '07 post facelift.

Rick

 

[MACK]

It's not ideal for bulb changing purposes but it you've broke the mount for the rear cover and havent got the pieces for plastic welding you may get away with silicone sealing the rear cover in place. If your really lucky all you may have done is crack/smash the rear cover itself rather than the mounts for it on the headlamp unit. If it's just the cover obviously you replace this insitu at circa £7 for a cover from the dealer. Anything else and it's a bumper off job unfortunately. Hopefully whatever your up against you won't need to go to the expense of a replacement headlight.

 

[Ducklakeview]

Silicone will not seal it effectively. You are wasting your time doing that, and numerous forum members have tried and failed.

https://z4-forum.com/forum/search.php?keywords=seal+headlight+silicone&terms=all&author=&sc=1&sf=all&sr=posts&sk=t&sd=d&st=0&ch=300&t=0&submit=Search

The rear cover is held on quite tightly by it's fixings, with a fair degree of compression on the seal. As you drive, the top rear of the headlight will be pelted by wind & rain, and silicone will not seal this for more than a few miles. You need to improvise and rebuild the snapped "bracket" so that the end of the cover is held tightly against the lamp body. The retaining clip is not enough, as it doesn't apply pressure at the broken clip end. Have a look at the end of the cover, if it is only that which is broken, they are £15 odd from BMW, BUT I doubt it will be the cover that is broken, as it's a lot "chunkier" than the clip it sits in.

Mike

 

[Ducklakeview]

As an aside, I have a few sets of rear covers knocking around in the garage, you are of course welcome to one if that is the problem.

Mike

 

[MACK]

Silicone will not seal it effectively. You are wasting your time doing that, and numerous forum members have tried and failed.

https://z4-forum.com/forum/search.php?keywords=seal+headlight+silicone&terms=all&author=&sc=1&sf=all&sr=posts&sk=t&sd=d&st=0&ch=300&t=0&submit=Search

The rear cover is held on quite tightly by it's fixings, with a fair degree of compression on the seal. As you drive, the top rear of the headlight will be pelted by wind & rain, and silicone will not seal this for more than a few miles. You need to improvise and rebuild the snapped "bracket" so that the end of the cover is held tightly against the lamp body. The retaining clip is not enough, as it doesn't apply pressure at the broken clip end. Have a look at the end of the cover, if it is only that which is broken, they are £15 odd from BMW, BUT I doubt it will be the cover that is broken, as it's a lot "chunkier" than the clip it sits in.

Mike

OP I don't really share the above assessment. At the end of the day there are plenty of folks who have had success sticking the lens back on with front with various sealants etc (after a clear indicator/angel eye swap). I dont see why something similar cant be achieved at the back. The only issue with sticking the back on in a similar if done well that I foresee is having to disturb it all to change a bulb down the line. Obvious i could be wrong but either way OP I think it's got to be worth a try if all else fails and your staring down the barrel of having to buy a new light.
That said the mounting lugs do tend to be the failure point and as there's a repair fit from BMW for circa £15 that's relatively easy to fit, let's hope that's one issue and the condensation is just a badly sealing cover or even a result of the time of year etc.

 

[RickZ4]

Thanks for all the input, guys Yes, the cover is much more chunky and was undamaged.

Most of the condensation clears fairly quickly if I go for a drive with the lights on, just leaving the indicator fogged. I was up early this morning and managed to get it through the MOT, so I now have a bit more time to think about it. I did read the other condensation threads and (along with some of the comments here) on balance think I may have to bite the bullet for a long term solution... :|

I see one or two advertisers on eBay who are breaking for spares.