Opinion on spring rust wanted

[New Duke]

My track year starts next week so I got the car up today and did a thorough look underneath. Only new thing I spotted was some rust on the rear drivers side spring right at the top. I peeled away more of the plastic sheathing and found more rust. I gave it a tap and a scrape with a screwdriver but couldn't really tell if it's surface rust or totally eaten through.

Photo below. Opinions please?! I have a brand new set of PZ suspension from the GB that I've been saving as spares. So I'm wondering whether this level of rust here is normal, or if I should be booking in with a fitter to get the new PZ suspension fitted asap.

[PeteH]

The highest stress in a spring is on the surface, so any surface rust that causes pitting will likely break the spring. A spring is very different to most other components in this regard, and it's why we see so many broken springs.

I'd definitely say it's time to change.

[New Duke]

That's exactly where the rear springs break first

[New Duke]

Thanks guys, much appreciated. Will book it in to get the PZ set fitted then will get the alignment done.

[Dr. FrankenRex]

I know you're on about coming up my way to get some bits and pieces from my archives

I could quite easily give you a hand whipping them off and swapping them over in the barn if you have the time? Would obviously need alignment doing afterwards but would still be OK to drive to a nearby place


EDIT: Not involved with the GB, but assuming these come pre-assembled rather than spring and shock separate? If it involves spring compressors then pay someone qualified to do it

[xamtex]

you gets springs in one box and shocks in another...no top mounts so it is a compressor jobbie.

[qwakers]

its only a compressor jobbie to disassemble the old units to get the topmounts. then new ones can go together without the need for spring compressors.

[warpc0il]

or cut the old spring with an angle grinder to release the pressure

[qwakers]

who told you i did that!

[warpc0il]

I've done it a few times, over the years, and at least an angle grinder is less effort than a hacksaw.

It only works on units where the spring preload is less than the length of the thread, otherwise it still doesn't help get the new spring loaded.

Ratchet straps don't work as spring compressors DAMHIKT

[qwakers]

ratchet straps do work as spring compressors. you need two and a big vice, but it can be done.


youll lose a fair amount of skin when it goes wrong though!

for legal reasons...

dont try any of the above bodges at home!

[PeteH]

You've forgotten the "leave it on the car, take the top nut off, then jack the car up". Most of the time that doesn't decapitate you either.

[qwakers]

to be fair, cutting the spring with the strut still assembled is relativly safe, it relives the spring tension but the spring cant go anywhere, as the damper rod prevents any real movement, just mind your fingers, incase the disk grabs when the spring seperates.

[Rotary Potato]

Unsurprisingly ... I have previous here ...

BMW E36 325 - night before a drift weekend, probably about 10 years ago now. We'd just tickled the diff with a MIG, so just the springs to cut and job's a goodun ... all ready for some slidey slidey.

I went to grab my spring compressors out the boot and realised I'd left them at home. So I decide to cut them on the car (jacked up, but still sone tension on them). The 'plan' was to cut 99% of the way through and then tap with a hammer to pop off the bottom coil. First spring, absolutely perfect - a little tap with the hammer and 'ping' it broke perfectly.

"Bet you can't do that again" said my mate. He was right. The other side gave way while I was attacking it with the angry grinder. The cut coil fired into the ground between my legs and launched itself skywards, missing my arse by a few mm, and hit the roof of the full height barn we were in.

After that near miss I decided the rear was low enough already!

[Essex2Visuvesi]

Probably not a safe way to do it:-


Adam and I met a chap last year who was hit in the face with a coil spring that escaped from a coil spring compressor.
From memory he lost most of his teeth and his jaw and cheek were held together with metal plates.
Did us a good deal on some Audi S3 Alloys tho

[Rotary Potato]

... Adam and I met a chap last year who was hit in the face with a coil spring that escaped from a coil spring compressor. ...

Yep ... I done that too.

Luckily managed to wind off a lot of the tension before they slipped fully off, so while it knocked me on my arse, gave me a black eye & broke my glasses, there weren't any life changing consequences.

I now always use 4 compressors on each spring, rather than just two.

[New Duke]

I know you're on about coming up my way to get some bits and pieces from my archives

I could quite easily give you a hand whipping them off and swapping them over in the barn if you have the time? Would obviously need alignment doing afterwards but would still be OK to drive to a nearby place


EDIT: Not involved with the GB, but assuming these come pre-assembled rather than spring and shock separate? If it involves spring compressors then pay someone qualified to do it

I'll see if bigpete is still fitting them as yeah it's a compressor jobbie. Really appreciate the offer though, thank you.

Thanks for being so patient about me picking up those parts. I'll propose some dates soon, honest. I'm aching to see the ported monster in the flesh.