A Rear Rattle that'll drive you mad.

[Faheem]

I just cut up one of my finest belts to make little supports for the fuel tank. Put everything back together and the wretched stinking rattle is still there.

 

[Low Rider]

Dam now that's a pain

 

[Faheem]

So, a new discovery, if I lightly press the brake whilst driving the rattle will go away completely, not the handbrake but the actual foot brake. Thoughts?

 

[Low Rider]

Sounds like your getting to the bottom of your problem.
Have you worked out which side is giving the noice

 

[Faheem]

Yes, drivers side, rear. The caliper spring is intact and if I remember right I actually replaced it when I got the car, the pads still have plenty of life left but if all else fails I'll be putting in new pads. I feel like there may be some tiny stones or some crap that is stuck there, although I can't imagine how it would get in there. @t-tony have you ever had such an experience with a car, I ask you this as you're the forums most reputable mot tester

 

[jonco]

Yet another possibility - unfortunately there are many - is the brake shoe retainer pins - Part 7 on this http://www.realoem.com/bmw/enUS/showparts?id=CH72-EUR---Z3-BMW-Z3 1.9&diagId=34_0930

I had this on mine and after similar investigations to those already mentioned it it failed completely and the shoe flopped about - now that sounds like somebody has a grinder in the boot!

If you have axle stands then jack the back end up/remove road wheels and run the engine in first gear/low revs you should be able to pinpoint the source if it's from a rotational function.

 

[g8jka]

I remember fitting a cheap pair of rear brake pads to my old E36 which caused a rattle, went away when I pressed the brake lightly, New pads cured the problem. Might be worth checking the pads aren't rattling.

 

[t-tony]

Quite often a stone or something can get in the calliper and rub on the disc, but that usually produces a scoring or rubbing noise. Silly question, are the anti rattle springs fitted correctly, there was a post the other week where someone hadn't fitted them right and that means there isn't enough tension on them to keep the calliper still.
Can you post a picture of the calliper and Spring please? Also if you can measure the distance between the holes where the anti rattle Spring locates I think I have a pair of new ones at work.

Tony.

 

[Faheem]

Funny thing is its only over bumps so @jonco if I put it on axle stands and ran it a low gear I probably wouldn't hear the noise.

@g8jka I haven't changed the rear pads since I got the car a year ago but the problem wasn't present when I got the car so before I lose all hope and change pads my goal is to see if something is lose, worse comes to worse I'll put a new set of rear pads in.

@t-tony thanks mate what I'll do is I'll post the picture of the spring early tomorrow but when this noise had started to come originally I took the spring off, inspected it and reinstalled it, it *looked* fine but I'll try rob a caliper spring from my dad's e36 and see whether that cures the problem.

 

[Antm72]

The original video shows the rattle with the car stationary It may well be as suggested be the brake shoes but applying the brake pedal would cause the pads to move not the shoes.
I would strip the rear brakes down it looks like you have narrowed it down

 

[g8jka]

I would also strip the rear brakes down, its a fairly simple job and whilst doing it you get chance to clean everything up. Even if you don't find the problem to be there you have done some decent maintenance to the rear brakes which is never a bad thing on these cars.

 

[Kev Bennett]

HI all
I had this problem last year and eventually turned out to be the rear brake pad carriers,previous owner had filled them to make brake pads fit so pads eventually worn and didn't fit tight enough !!!

 

[Kev Bennett]

As above post I am sure this is the part no 34211164398 brake carrier and they where approx £ 60 per side from BMW

 

[colb]

Have a look here
http://www.zroadster.net/forum/viewtopic.php?f=5&t=40604&p=376643#p376643

Annoying rattle traced to handbrake linkage thread also describes cure with pictures

 

[DavidM]

Excellent let's hope you've found the problem Faheem. I guess the reason you are unable to hear the noise with the roof down is because the road and wind noice drowns the sound of your rattle out

Or maybe it is something below the hood area and hoodwhen down, rests on whatever is rattling, supressing the noise - just a thought?

 

[Faheem]

Thanks for all the support. I finally fixed it today, even though it is only a temporary measure until I find enough time to fix the issue permanently.

The problem was the clips on the brake pad that push it and hold it into the piston, this clip had detached itself from the pad and was rattling about in the piston. As a temporary measure I used some super strong glue to secure the clip back into the pad (you mix the resin with the hardener and you'll have yourself a very powerful glue, at least once it sets). I'm not expecting it to last till the pads wear down but until I find the time to replace both of the rear brake pads it will do. As you can see the pads themselves have a fair amount of life left in them.

After allowing it to settle completely I took it for a test drive and sure enough the noise had gone, at least 95% of it, I'm assuming that the issue will be fixed permanently when I do replace the brake pads.

In all honesty I am extremely pleased that the issue was only the brake pads and nothing more serious, I did find that my fuel tank wasn't properly supported but besides that, the subframe and the diff bushes are all intact which is fantastic news.

 

[Low Rider]

I'm pleased you've managed to get to the root of your problem Faheem.
Thankfully not an expensive fix

 

[g8jka]

Glad you found the problem and it won't be an expensive fix when you get round to doing it.

 

[t-tony]

Thanks for all the support. I finally fixed it today, even though it is only a temporary measure until I find enough time to fix the issue permanently.

The problem was the clips on the brake pad that push it and hold it into the piston, this clip had detached itself from the pad and was rattling about in the piston. As a temporary measure I used some super strong glue to secure the clip back into the pad (you mix the resin with the hardener and you'll have yourself a very powerful glue, at least once it sets). I'm not expecting it to last till the pads wear down but until I find the time to replace both of the rear brake pads it will do. As you can see the pads themselves have a fair amount of life left in them. View attachment 39847View attachment 39848

After allowing it to settle completely I took it for a test drive and sure enough the noise had gone, at least 95% of it, I'm assuming that the issue will be fixed permanently when I do replace the brake pads.

In all honesty I am extremely pleased that the issue was only the brake pads and nothing more serious, I did find that my fuel tank wasn't properly supported but besides that, the subframe and the diff bushes are all intact which is fantastic news.

Happy to hear you've got to the root of the problem mate, and nothing too expensive either. Result.

Tony.

 

[DavidM]

Well done - you will think the car is quieter than quiet when fixed and driving normally again!