Suspension springs.

Mikejaytee · 23rd February 2017, 20:24

Having recently had a front spring breakage on my Tourer, and given the number of threads and posts in regards to spring breakage, I thought I would update my own experience and research for those interested.

On removing the spring, it was clear that there was significant corrosion under the plastic 'isolator' at the base of the spring. The rest of the spring ( all that was visible when on the car ) was perfect/pristine; no damage or rust, just shiny original paint. Therefore it is evident that the corrosion, caused by the trapping of water/salt/grit between the isolator and the spring, (and probably never actually drying out ), was such that surface damage and imperfections from grit and corrosion were the cause of the eventual fracture. The fracture was about 9 inches from the end of the spring in the first coil and under the isolator. I would guess that most, if not all spring breakages occur where there is corrosion. ( Has anyone had a breakage on a clean/painted/undamaged part of their spring/s ?)

The isolator is therefore a problem, in that it prevents easy washing/cleaning and maybe waxoyling the very base of the spring; something which is worth doing when you have the wheels off once a year or so.

So, on reassembling the spring/strut, I have applied copious waxoyl within the isolator, and then on top of the isolator around the base of the spring. This should prevent as much damage as possible, for as long as possible, especially if I re-apply waxoyl or grease once a year or so.

For those looking for new springs, this seller on Ebay has pretty much all types for the 75/ZT owner. http://myworld.ebay.co.uk/buycarspares2/
Brands are KYB, Suplex etc, respected manufacturers and suppliers of both OE and aftermarket suspension components. This seller is very helpful, and will ensure you get the right springs for your car. Listings have all spring dimensions and compatibilities, so you can work out which springs you need yourself if you have the old spring/s off the car and can take some measurements. Euro car parts also has some items at good prices, from Anschler, another well known brand. Rimmer Bros also have most of the variants.

If you have rusty springs, or can get to inspect the base of your springs underneath the isolators and find them rusty, then replacement is a good idea before they fail. My offside spring is nowhere near as corroded as the nearside; the nearside usually ( probably ) getting more rain, salt, grit etc from the side of the road. The car has only done 50,000 miles and is in great condition otherwise.

My main concern when approaching the replacement was whether the pinch bolt at the base of the strut would come undone without trouble. In the event I cleaned and oiled all around the bolt, and applied a little heat from a heat gun to the area of the hub knuckle where the threaded part of the pinch bolt was held. Using a good quality hexagon socket and a good extension bar, I found that the bolt came out without any trouble, albeit slowly and with some effort! Don't be tempted to try with a 12 point socket, or one that is a poor fit... Make sure you have a tight fitting good quality socket, and plenty of leverage via extension bar or breaker bar. Two to three feet of leverage is useful and necessary, and also means less effort on your part. Once moving, the bolt can be undone bit by bit; I take my time due to age.... ( me, not the car ). I know some prefer to remove the whole hub assembly and work off the car, and this may be necessary if you have a stripped bolt head...but working on the car allows more leverage to be applied to the bolt head if it is still in good condition. I'm also for as little dismantling as possible for a given job, and as long as you can shift the pinch bolt you are home and dry...apart from compressing the spring to dismantle and rebuild the strut.

I trust this is helpful to at least a few members who are concerned about their springs. I'm happy to discuss with any fellow member if this is helpful, either by PM or phone...

T-Cut · 24th February 2017, 13:37

Quote:

Originally Posted by Mikejaytee

Therefore it is evident that the corrosion, - - - - was such that surface damage and imperfections from grit and corrosion were the cause of the eventual fracture.

It's all in line with the technical literature on the causes of spring fracture. Here's some examples:

Ref 1: http://www.sciencedirect.com/science...13290213000515

Ref 2: https://www.researchgate.net/publica...ication_detail

More: https://www.google.co.uk/#q=vehicle+...cture+research

TC

23rd February 2017, 20:24	#1
Mikejaytee Regular poster Rover 75 Tourers x 2. Join Date: Jul 2016 Location: Galloway. Posts: 51 Thanks: 10 Thanked 14 Times in 10 Posts	Suspension springs. Having recently had a front spring breakage on my Tourer, and given the number of threads and posts in regards to spring breakage, I thought I would update my own experience and research for those interested. On removing the spring, it was clear that there was significant corrosion under the plastic 'isolator' at the base of the spring. The rest of the spring ( all that was visible when on the car ) was perfect/pristine; no damage or rust, just shiny original paint. Therefore it is evident that the corrosion, caused by the trapping of water/salt/grit between the isolator and the spring, (and probably never actually drying out ), was such that surface damage and imperfections from grit and corrosion were the cause of the eventual fracture. The fracture was about 9 inches from the end of the spring in the first coil and under the isolator. I would guess that most, if not all spring breakages occur where there is corrosion. ( Has anyone had a breakage on a clean/painted/undamaged part of their spring/s ?) The isolator is therefore a problem, in that it prevents easy washing/cleaning and maybe waxoyling the very base of the spring; something which is worth doing when you have the wheels off once a year or so. So, on reassembling the spring/strut, I have applied copious waxoyl within the isolator, and then on top of the isolator around the base of the spring. This should prevent as much damage as possible, for as long as possible, especially if I re-apply waxoyl or grease once a year or so. For those looking for new springs, this seller on Ebay has pretty much all types for the 75/ZT owner. http://myworld.ebay.co.uk/buycarspares2/ Brands are KYB, Suplex etc, respected manufacturers and suppliers of both OE and aftermarket suspension components. This seller is very helpful, and will ensure you get the right springs for your car. Listings have all spring dimensions and compatibilities, so you can work out which springs you need yourself if you have the old spring/s off the car and can take some measurements. Euro car parts also has some items at good prices, from Anschler, another well known brand. Rimmer Bros also have most of the variants. If you have rusty springs, or can get to inspect the base of your springs underneath the isolators and find them rusty, then replacement is a good idea before they fail. My offside spring is nowhere near as corroded as the nearside; the nearside usually ( probably ) getting more rain, salt, grit etc from the side of the road. The car has only done 50,000 miles and is in great condition otherwise. My main concern when approaching the replacement was whether the pinch bolt at the base of the strut would come undone without trouble. In the event I cleaned and oiled all around the bolt, and applied a little heat from a heat gun to the area of the hub knuckle where the threaded part of the pinch bolt was held. Using a good quality hexagon socket and a good extension bar, I found that the bolt came out without any trouble, albeit slowly and with some effort! Don't be tempted to try with a 12 point socket, or one that is a poor fit... Make sure you have a tight fitting good quality socket, and plenty of leverage via extension bar or breaker bar. Two to three feet of leverage is useful and necessary, and also means less effort on your part. Once moving, the bolt can be undone bit by bit; I take my time due to age.... ( me, not the car ). I know some prefer to remove the whole hub assembly and work off the car, and this may be necessary if you have a stripped bolt head...but working on the car allows more leverage to be applied to the bolt head if it is still in good condition. I'm also for as little dismantling as possible for a given job, and as long as you can shift the pinch bolt you are home and dry...apart from compressing the spring to dismantle and rebuild the strut. I trust this is helpful to at least a few members who are concerned about their springs. I'm happy to discuss with any fellow member if this is helpful, either by PM or phone... __________________ [SIGPIC][/SIGPIC] Best regards, Mike.