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  #11  
Old 18-09-2018, 06:59 PM
mnbrennan mnbrennan is offline
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I was worried too about dropping the subframe, but managed with a couple of trolley jacks. Have a look in my rhubarb journal
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  #12  
Old 19-09-2018, 01:01 PM
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c_w c_w is offline
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Quote:
Originally Posted by Howm58 View Post
Thanks for all the responses guys.
I am based in Redditch, Worcestershire. I have received a Meyle original bush that I will use as a pattern to make the necessary 'eared' parts of the pressing tool. I have ordered the 'can' & high tensile allthread from an Ebay tool supplier who found me the nearest sizes at a fairly reasonble price.
Subframe removal is probably the way to go as i will be able to rustproof the rear chassis/floor unhindered, but lowering (& raising) the whole unit on my own worries me a little.
As stated,crawling about underneath the car will probably show me the path to take.
Keep going down to the garage however, looking at the beast & saying "one last blast before he goes up on stands!!!"
I had mine off twice last year as I made changes to the bushes. The second time I had the whole rear end removed in about 40minutes! (It's really easy, and even changing the diff I'd consider dropping the lot to save the hassle refitting the diff subframe bolts which are notoriously hard to start off.)



In essence though removing is goes something like;

- Jack up the car and rest axle stands on the rear jacking points
- disconnect bottom shock bolts
- disconnect 13mm anti roll bar nuts from the trailing arms
- remove exhaust back boxes
- disconnect handbrake cables
- disconnect speedo sensor
- undo 4 16/17mm nuts diff to propshaft
- remove subframe side plates (usually rusty allen bolts, replace them with stainless normal bolts IMO)
- undo the big subframe nuts and rear diff nut
- I used a trolley jack with a flat block of wood under the diff and lowered it all down. It balances pretty well. Keep it on the jack so you can withdraw it from under the car and don't drop it all the way down to the floor otherwise you might deform the brake disc backplates.

The *only* issue on removal that could cause a problem is the handbrake cables which may not want to play and be stuck in the hub. As I had two new cables I just cut through them to remove the subframe and tackled removing the cable from the hub later. Or you can just disconnect them at the handbrake end and feed them through.

The only other technical part when refitting is lining up the diff flange to the propshaft. It needs to be slotted in at the same time you are rising the subframe up. If you put the subframe up in to position without the propshaft relocated it's next to impossible to slot it on, so do it when there is a bit more to play with when the subframe is hanging down a bit.
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  #13  
Old 19-09-2018, 09:45 PM
Howm58 Howm58 is offline
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Twice in one year, WOW.
Don't think you're that crazy, having just removed the back boxes. Apart from wondering how to get from under the car with a silencer on my chest (they are NOT light) things came apart fairly easily.
Without the exhausts in the way the rear subframe assembly seems smaller than I thought. I have a couple of decent trolley jacks so the whole lot will probably come off now!!
Bush pulling tool almost complete, just got to spark out the spacer with the 'ears' that locate around the bush onto the frame.
Looking underneath, it would now be quite rude of me to put everything back without changing the clutch!!!
I'll see how I get on at the back end first.
Howard.
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  #14  
Old 19-09-2018, 10:07 PM
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It was twice in one week as I put powerflex subframe bushes on but after a short test drive I went back to new oe subframe bushes. They also got inte way of my new adjustable eccentric bolts on the trailing arm as the powerflex bush has a large hat top half which cups over the subframe.
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  #15  
Old 20-09-2018, 06:31 PM
JuhaV JuhaV is offline
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Hi,

Please take a look here and scroll down to see more pics. Some of them so how to remove the subframe and how to put in new poly bushes.

https://plus.google.com/photos/11351...LXkmuWj46W42wE

Do not have M Coupe any more but still visit the forum every now and then.

br, Juha
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  #16  
Old 27-09-2018, 12:32 PM
Howm58 Howm58 is offline
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Thanks JuhaV,
I am almost there. Everything that I thought would be difficult to undo has been much easier, even the bolts with the 6mm allen key ends!!
Found that 'Plus Gas' still exists! Bought an aerosol can when we were down in Cornwall, seems to work MUCH better than WD40.
The bush pulling tool is now completed (my toolmaker at work did a few hours of subcontracting for BMW!!).
Still in 2 minds about dropping the subframe completely, but I have an old supermarket bakers trolley that I use to wheel about machinery & it just slides over the top of my trolley jacks front wheels. my main concern is preventing damage to the rear disc backing plates when lowering the subframe. The trolley should keep it well off the ground & easy to manoeuvre from beneath the car, solving the other problem that worried me (getting the damn thing from under the car).
Would post some photos if i knew how.
Howard.
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  #17  
Old 27-09-2018, 03:46 PM
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c_w c_w is offline
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Oh another tip is to remove the rear calipers and zip tie them to the body - this way you don't need to disconnect the hydraulic lines.
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  #18  
Old 27-09-2018, 03:59 PM
cosmas cosmas is online now
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When removing mine I found that taking the carbon filter off the fuel tank improved access to the 2x hex bolts on the passenger side.
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  #19  
Old 29-09-2018, 05:21 PM
Howm58 Howm58 is offline
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Well it's off!!
OMG that was an effort! Yes it does balance on the jack but it's terrifying until you get to that point (wondering which way it may tumble!!!). I inched it down using 3 axle stands under the ends & centre of the beam.
It is bloody heavy as a unit, I can now see why some split the diff from the beam. May need some help jacking & lining up when re-installing.
The mounting bushes popped out very easily with my home made tool (well, mostly made at work!), 10 minutes a side & no heat needed. Applied Plus-Gas 30 mins before & hey presto!!
Busy rust removing rust on both chassis & subframe unit at the moment. 2 pack paint doesn't like cold, damp weather so I'd better get my skates on.
Thanks for all the input so far guys.
Howard
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