New springs fitted and Maxum's how to

[PawnSacrifice]

This is a how to for changing the springs. Not really my own work… credit must go to Maxum, his original work is here...
Up Date - Wheel Gap has gone

It's not a to hard job, the rears will take about 15/20min per side including jacking it up and taking the wheel of, once the wheel is off there is one bolt to remove that hold the rear shock to the swinging arm, once out just push down on the brake disc at the same time yank the spring out,
pop the new spring in, connect the shock back on, wheel back on job done
The front are a bit more involved, not many bolt to take out just two at the bottom, one large one that clamps the front shock to the front hub and one nut the hold the link rod from the anti roll bar to the shock you just need to undo the top one, push down on the front hub until the shock slides out of its clamp, use plenty of WD40, then under the bonnet there are 3 nuts for the top mounts remove them, you will need a good set of spring compressors, compress the spring until the top mount fells lose then remove the dust cap in the middle of the mount and then you will see one nut undo that and then the top mount will come of , unwind the compressors and remove the springs, do the job in revers when fitting the new springs, job done. an hour for each side should do it. you just saved your self £300.00, even if the have to buy your self some tolls for the job it will still be a heap cheaper.
Good luck

As you can see, a distinct lack of pictures. So, having done mine today using the above and the BMW TIS for reference I took some pictures and will annotate as I go - this is plagiarism.

 

[PawnSacrifice]

Rear Springs - as Maxum said, not a hard job. The TIS has you dismantling a load of other bits, but the method above worked for me.

With the car jacked up and on axel stands, the wheel comes off and here's the start point.

Undo the bolt at the bottom of the shock...

When you removing the bolt lower the brake / wishbone gently.

Push down on the top of the brake disk and pull the spring out...

Old spring and new:

Assembly is the reverse of the above with one slight variation. Once the spring is located use a scissor jack to lift the assembly up until the bolt can be inserted easily.

That's the rear done.

 

[PawnSacrifice]

Front springs - not difficult, but can be fiddly.

Again, jack the car up, put it on stands and remove the wheel. Ready to begin...

There are two bolts to remove, once the are things can fall down, so a scissor jack can be used to take the strain - letting the assembly drop quickly is a bad idea as there are a few hoses / cables at the back of the disk which could be damage, as well as the protection plate.

First bolt - socket on the front and a spanner on the back, which is a little fiddly.

Second bolt - where the socket is, you can just about see it behind the top of the protection plate.

Once this one is out, jack away the assmbly needs to drop down. I put an empty oil container down to soften the blow and stop it falling too far.

Undo the bolts two turns each to allow the shock to move.

To drop the wishbone / brake assembly off the bottom of the shock, make sure everything is properly WD40'd, push down on the disk and also give the shock a little push, back and forth, left and right.

Once the bottom of the shock is free from the clamp, undo all three bolts on the top of the strut mount (in the engine bay) and remove the shock assembly.

Prop up the disk with the jack and take the show to somewhere it can be worked on.

Pop the end cap off - the bolt inside can be removed after the springs are compressed - do not attempt to remove it with the springs un-compressed.

Apply the spring compressors. Try and keep them equidistant apart, gradually tightening each one in turn, move on to the next once it becomes loose. Keep going until the spring is tightly compressed - with the compressors in the picture, until they bottomed out.

Undo the bolt shown 2 pics above - this will require some force and a little patience, it is not the easiest to work on. Once the bolt is removed, take out the top mount and remove the spring.

Release the spring compressors working in the same method as before, a little at a time.

Old and new spring.

Compress the new spring in the same way as before. The reassemble the shock / spring.

Ready to go back on the car.

Feed the shock up, and lightly fasten the top mount nuts - to allow movement to position the shock.

Once the shock is relocated in the clamp, push the disk upwards until it is in place. Using the scissor jack will help - actually works best under the wishbone.

Fasten the bolts around the strut and then tighten the top mount.

Front done.

 

[PawnSacrifice]

A few pointers from my experience.
1. Try and keep everything as gradual as possible to ensure no hoses or cables are damaged.
2. I used Draper spring compressors, while they seem well made they were a little too industrial for the Z4 setup - something with a little more finesse is required. Ideally.
3. Because of the force involve to get some of the nuts / bolts free I would say axel stands are a must.
4. The BMW TIS instructions, while more complete, require far more parts to be disconnected, I think Maxum's instructions were spot on, just want to make people aware that they do include short cuts - that I would use again.

Time wise the rears took about 20 minutes a go and the fronts total was 3 to 4 hours, excluding breaks and faffing about taking pictures.

Almost forgot, I went with Supersport springs as they claim to drop the car just 20mm - Eibachs and 30mm would be too much with the M wheels. I'm hoping this is the car - seems about on the money so far. Will feedback on the ride etc in a couple of weeks once they've settled and I've had the geo done. That is assuming there is no rubbing in which ace they're coming off again.

Pics of the car - not quite the same spot, but it had been turned around in between.

Before:

After:

Maxum, owe you one

 

[imp75]

Excellent report! Posts like this give me confidence to try stuff myself!

 

[srhutch]

Can you get it out of your garage OK Matt, from your foam video doesn't look like a lot of ground clearance.

I'm sure you've checked though :wink:

 

[PawnSacrifice]

Excellent report! Posts like this give me confidence to try stuff myself!

To be honest I only gave it a go as I'd read Maxum's post on what to do - also when I mentioned I needed to get a price for fitting, someone said, "you not doing them yourself then?" As if that was the obvious choice. So, thought I'd give it a go... there is nothing technical here, it is all about confidence. And spring compressors.

Can you get it out of your garage OK Matt, from your foam video doesn't look like a lot of ground clearance.

I'm sure you've checked though :wink:

With some of the cars that have been on there I thought I'd be fine - although I was a little worried he playalistic's Eibached M grounded the heat shield yesterday. Yikes! But all seems to be okay.

 

[AlanJ]

Nice 'HOW TO' thanks

 

[Dreamer]

Looks really nice

Whole car is really coming together well. Looking forward to the report back after geo

 

[skillick]

Another pointer.... when you are taking the offside front apart.... be careful with arm on the autolevelling switch... otherwise you'll end up having to replace either just the arm or the whole sensor!!

 

[big_al]

Have to say, this was VERY useful - thanks to all involved.

From doing the rears, I found that jacking just 1 side up made it very hard to lower the hub with just the lower shock bolt out - the anti-roll bar was holding it up (as the other wheel was taking even more load than usual. I ended up jacking the whole rear up, which made it a LOT easier. Hope that helps someone else.

Now for the fronts and discs and pads etc etc....

 

[Marius]

Same at the front, jack both wheels to release pressure of anti roll bar

Sent from my LT18i using Tapatalk 2

 

[gr3mlin]

Any info on Torque settings, tried to find some BMW TIS manuals but no luck, going to give this a try next weekend after finding a cracked rear spring.

 

[ben g]

Any info on Torque settings, tried to find some BMW TIS manuals but no luck, going to give this a try next weekend after finding a cracked rear spring.

As tight as you can go seemed to work for me. Had my springs on a year now with no problems.

Does everyone use them pads on the rear springs? Thought about removing mine off my aftermarket springs to go that little bit lower at the rear.

 

[Darkangelv2]

Apologies, Massive thread resurrection!!!

I used this guide this weekend - thanks so much PawnSacrifice (if you're still here?!)!

One bit of really useful info would be the socket sizes required which would have saved me a bike ride to Halfords half way through (none of my 3 sets had an 18MM socket!).

Also, I've only done the rear so far as I hit issues with the front end (insufficient spring compressors).

For the front, can anyone let me know if it's ok to atleast de-torque the bolt in the top of the front strut whilst it's all bolted up? It's going to be a bugger to steady/grip the strut on my own whilst giving it enough oomph to get it undone when off the car....

 

[ZermattV]

PS was last seen tracking his 924 writing about his 911 SC in GTPorsche .

 

[adam1985]

Apologies, Massive thread resurrection!!!

I used this guide this weekend - thanks so much PawnSacrifice (if you're still here?!)!

One bit of really useful info would be the socket sizes required which would have saved me a bike ride to Halfords half way through (none of my 3 sets had an 18MM socket!).

Also, I've only done the rear so far as I hit issues with the front end (insufficient spring compressors).

For the front, can anyone let me know if it's ok to atleast de-torque the bolt in the top of the front strut whilst it's all bolted up? It's going to be a bugger to steady/grip the strut on my own whilst giving it enough oomph to get it undone when off the car....

Hi Darkangelv2 do not detorque the bolt in the top of the front strut at anytime unless the spring compressors are on the spring as it will release all of the energy stored in the spring. I had to use two sets of spring compressors to to sufficiently compress the spring when I changed mine.
IIRC Once compressed you should see that the top of the thread that you remove the bolt from has a allen key slot. What i did was put a socket onto the nut then pass the allen key through the socket and then use a spanner to twist the nut while holding the allen key.

 

[Darkangelv2]

Apologies, Massive thread resurrection!!!

I used this guide this weekend - thanks so much PawnSacrifice (if you're still here?!)!

One bit of really useful info would be the socket sizes required which would have saved me a bike ride to Halfords half way through (none of my 3 sets had an 18MM socket!).

Also, I've only done the rear so far as I hit issues with the front end (insufficient spring compressors).

For the front, can anyone let me know if it's ok to atleast de-torque the bolt in the top of the front strut whilst it's all bolted up? It's going to be a bugger to steady/grip the strut on my own whilst giving it enough oomph to get it undone when off the car....

Hi Darkangelv2 do not detorque the bolt in the top of the front strut at anytime unless the spring compressors are on the spring as it will release all of the energy stored in the spring. I had to use two sets of spring compressors to to sufficiently compress the spring when I changed mine.
IIRC Once compressed you should see that the top of the thread that you remove the bolt from has a allen key slot. What i did was put a socket onto the nut then pass the allen key through the socket and then use a spanner to twist the nut while holding the allen key.

You legend, thanks very much. I've bought a much better set of spring compressors now (specifically call themselves MacPherson Strut type) which look like they'll be safe and secure.

I had read about an allen key being used to hold the strut but struggled to see how it will be done when I had it in front of me. My sockets don't have a way of using a wrench on them so not sure how I will manage that. In case, I've bought a clamp that secures to the strut without damaging it and you can put a spanner on that.

Either way, I won't touch the bolt until I'm compressed.

 

[adam1985]

I had a socket like the one in the link below which I think was for a spark plug. It has a flat on it that I put the spanner on. I'm not sure what size you need.
http://www.tesco.com/direct/toolstream-spark-plug-socket-set/214-8401.prd

 

[soundb0y]

Great guide will hopefully be following it in a couple of weeks!

My new z is just slightly too low and scrapes going into my garage and on speed ramps. Need to find out what springs are actually on it first.
Although it's been up on a ramp and nothings being damaged...