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_ethrty-Andy_

E46 Rear strut tophats

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havent a ton of experience with E46, but just having a look over a mates car and found something possibly?

On my E30, if you tighten up the bolt on the top of the shock, you can get it tight and the top mount does not move. Same as my Volvo.

However on the E46 i just looked at, the mount twists over a certain torque, and springs back to its original poistion. The tophats look new, but this just sounds a bit wierd? The top half of the shock twists with it, the bottom stays fixed in place.

Does this on both sides. Doesnt sound right to me? would have thought the thing should be solid save for the minute flex given its rubber?

Cheers

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chassis code JR47521 2001 318Ci Auto(GM) M43 cheers

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great thanks for that! i put next to no torque on them so i wouldnt have contirbuted to it. will recheck at some stage holding top of the strut/shock

how much twist should be acceptable though? does the fact that it springs back mean it should have a good bond still? they dont move back and forward/left to right

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it doesnt answer my question.

what im asking is should they be solid or are they able to twist a bit in perfect condition. on an E30s which is the only BMW i can compare it to, they dont twist at all. i only held the shock on the e30 to do it the last bit.

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If one is not allowed to check for twist, how can one know if they are dodgy then? If i hold the top of the shock and tighten the nut, that only confirms it is done up tight, not that the tophat is worn out or not. If twisting it is not alowed then how would be the best away to check if they are worn. They look new, but how would i know if they are teared from the hoop?

The amount i tried there is no question in the case of whether i contributed to wearing them out, they would have been able to twist before i did i touched. I put next to no torque on it and they twisted wuite freely. Somehting is still in contact though, given the fact the sprung back

Thanks for your help so far, hope this makes my questioon clear :)

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Take the shocks with mounts out and check them off the car

Edited by *Glenn*

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The rubber should be bonded to the metal shell and the centre sleeve .

If you can rotate the rubber within the metal shell or the sleeve within the rubber they have failed.

How can you establish this without twisting them - there should be no VISUAL separation between the rubber and the shell.

Cool will pass that on and check again! Cheers for that!

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What's the actual problem with this car ??... what does checking the rear mounts have to do with the problem ??

BTW: Rear shocks are not struts. Rear shock mounts are not top hats

Edited by *Glenn*

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havent a ton of experience with E46, but just having a look over a mates car and found something possibly?

On my E30, if you tighten up the bolt on the top of the shock, you can get it tight and the top mount does not move. Same as my Volvo.

However on the E46 i just looked at, the mount twists over a certain torque, and springs back to its original poistion. The tophats look new, but this just sounds a bit wierd? The top half of the shock twists with it, the bottom stays fixed in place.

Does this on both sides. Doesnt sound right to me? would have thought the thing should be solid save for the minute flex given its rubber?

Cheers

E46 mounts seem to be weaker than E30 and E36. I knocked out a set of E46 M3 mounts in less than a year on an E36.

The mount is the same size - if you want to go stiffer E30 convertible mounts seem to be favourite for E36 or E46.

However, on a stock 318 they may be intentionally soft for NVH reasons. If they are shot you'll hear a knock going over bumps.

Jo

Edited by Jo M

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What's the actual problem with this car ??... what does checking the rear mounts have to do with the problem ??

BTW: Rear shocks are not struts. Rear shock mounts are not top hats

well the owner thinks there is a knock coming from the back particularly when on hills etc, so i had a look at all the bushings and joins in the rear suspension so i could try and identify where it is coming from, and everything either is new in the last thousand kms, or hardly any older.

Yeah you are right on that. top hats are in the front with a beaing inside and look like a tophat. im not sure why i call them tophats. yep upper strut mounts. im not sure if the back was struts or shocks in back of an e46, i didnt look in behind the tyres, and dont recall from underneath what they are.

E46 mounts seem to be weaker than E30 and E36. I knocked out a set of E46 M3 mounts in less than a year on an E36.

The mount is the same size - if you want to go stiffer E30 convertible mounts seem to be favourite for E36 or E46.

However, on a stock 318 they may be intentionally soft for NVH reasons. If they are shot you'll hear a knock going over bumps.

Jo

Yeah have heard these are an upgrade. they certainly look similar. i would have recommended these if they are shot to the owner. thanks for 318i info though!

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If it was the struts/tophats/shock mounts/whatever they are called, wouldn't it be more of a 'rattle' rather than a knock? You would think that being suspension it would be more susceptible to every undulation in the road rather than just up hills?

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If it was the struts/tophats/shock mounts/whatever they are called, wouldn't it be more of a 'rattle' rather than a knock? You would think that being suspension it would be more susceptible to every undulation in the road rather than just up hills?

my thoughts too mate, but so far as i can see, its the only thing with a question mark on it. the jack and wheel chock is even bolted to the wheel well etc! if it was my car i would just drop it and bother about other stuff, but then i dont have a late model car lol

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If it was the struts/tophats/shock mounts/whatever they are called, wouldn't it be more of a 'rattle' rather than a knock? You would think that being suspension it would be more susceptible to every undulation in the road rather than just up hills?

It's usually a random clonk. The mounts don't have to look torn to have failed, either.

Jo

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might be E30 convertable mounts time. thanks so mch for your help people!

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might be E30 convertable mounts time. thanks so mch for your help people!

Why doesn't the owner get the car checked by somebody that actualy knows what to look for and check... then get the appropriate item repaired ?? Maybe's & I think it might be this, will not fix it

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Cheers for concern Glenn, they will be whether i look at it or not, as the person knows i have no experience with E46. i had a look for interests sake and see if i could see any obvious issues.

But i wouldnt learn anything if i didnt put my question up on here. i like to learn things and help other people learn.. contrary to popular belief im not on here just to comment at any possible opertunity, or every third post would be mine.

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Thanks Andi,

Being the owner of this car yes of course I will get her looked at. I had my rear suspension and all bushings given the all clear by a mechanic yesterday he had good news, he said its only about 15% worn on almost everything. But still not sure about those twisting rubber bits on the rear strut things (excuse lack of technical term). But there was nothing visibly worn and yet i get the occasional clunk in the rear

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Yeah checked that :) it's odd I can't fault a thing, even did the diff bush and yet i get a weird knock from under the car when I gently brake going down a hill or cornering down hill.. only happens once in a while on certain roads .. odd :s

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Yeah checked that :) it's odd I can't fault a thing, even did the diff bush and yet i get a weird knock from under the car when I gently brake going down a hill or cornering down hill.. only happens once in a while on certain roads .. odd :s

Did you do the diff bush or a mechanic? What do you mean by 15 percent worn? Either they are worn or not. How much junk is in the boot,maybe another mechanic is needed

Edit,excuse me if I'm a little blunt,just amazed that your not making any headway,especially being that it has been to a garage

Edited by Jono51

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Did you do the diff bush or a mechanic? What do you mean by 15 percent worn? Either they are worn or not. How much junk is in the boot,maybe another mechanic is needed

ex-BMW mechanic. im not sure how a mechanic can make a percentage like that, but everything looks new under there. nothing in boot most of the time checked that

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Are you sure the new rear diff bush hasn't been ruptured. The genuine bushes are oil filled and easily ruptured if not fitted correctly, even using the proper tool. You can't knock them in or apply unnecessary force on the center when installing them.

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if it wasnt done properly would there be oil like what im used to seeing or thicker etc? im not sure if it was genuine BMW or not, though most parts for this car are brought from Jeff Gray

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Maybe have a read of this and search around this forum for answers maybe. Or as I and others have said .... get another technician with BMW experience to have a look over it. Or go to the Dealer

http://forum.e46fanatics.com/showthread.php?t=755614

Edited by *Glenn*

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Maybe have a read of this and search around this forum for answers maybe. Or as I and others have said .... get another technician with BMW experience to have a look over it. Or go to then Dealer

http://forum.e46fanatics.com/showthread.php?t=755614

already had another technician look at it Glenn. Im wanting to know for my own knowledge. will have a look at that link :)

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