Compresion struts bolt snapping
Hi all has any heard of this happening i have heard a rumour about this
Is there anything i can to prevent this

 

use the right bolts for the application and a torque wrench...

 

andyescos on the site had both of his snap ,

iirc he upgraded the bolts from m8 to m10 and used a better quality bolt ,


im sure he will comment when he sees the thread ,


beef

 

hi yes i had both my bolts on the compression struts snap at the same time getting the car out the drive





the only yhing i can put it down to was the wrong grade bolts they were zinc plated not by me but came with the kit causes some thing called nitrogen embritlement scared the shit out of me ,what if it happened on the motor way id be dead
so i drilled & tapped them out to take m12 instead of the original m10 & used 8.8 grade bolt & torqued them up

hope this helps its certainly not a rumour ANDY

 

thats a bit shit! What manufacturer was that? And who does safe ones??

 

i got the kit off of comp brake but they came with the wrong grade bolts

 

If the compression strut was longer it could extend through the track control arm and and have a proper lock nut set up as per the original antiroll bar.

Far safer

 

I put stainless ones in mine. Held up so far on the street.

 

what is the torque setting for these?

my 3dr fired up today lol

 

Thankyou guys

 

torque setting anyone?

 

you couldnt find a worse bolt to use in a tensile area than stainless

 

there you go mate
m10, 30----38ft lb,s
m12, 52-----66ftlb,s

 

Wow and it hasn't snapped yet!


If you think I've put common grade 2 stainless bolts in my suspension then I challenge you to actually find a common grade 2 bolt that fits. I had to hit the airport boys just to find a supplier and the grade is A5. That bolt length and head only comes in A5 in my neck of the woods.

I torqued to 35lbft and went through a couple drill bits making a lockwire hole for the head.

 

fair play to you then, std stainless fasteners are terrible in shear strength, and no one on here will lock wire (well maybe a couple of us do )

 

I chose lower torque and lockwire to minimise snapping. Come from the track days I guess. Lockwire is easy to do with patience.

 

Heres a tip when fitting these, before you tighten everything up and drop the car down on its wheels check that you have a full suspension arc travel from full droop of your damper to full compression !You will almost certainly find that if the rose joint at the chassis end is anything but completely "plumb" that you will run out of travel and that the resultant "binding " of the top hats either side will cause the stresses that i reckon contribute to these problems at the TCA end ! I think Comp brake have addressed this issue but i still had to grind a 45 degree radius on the top hats to allow anything like full radius movement .

 

Yeah good call. If you just crank it on all tight then the angle will be off. Once it can't compress something has to give.

I took my spring off and tried the range of motion and it came out fine. Post of pic of the radius perhaps? We might see the difference in strut knuckles.

 

andy, cheers mate.

somethign else i better check then.

was going to fit the eccentric top mounts i have at some point, so will do this then.

i take it just removing the spring and a jack under the wheel to compress the damper will be ok?

 

I'd actually remove the damper completely , i know judging where the TCA will sit at rest can be difficult but you'll be surprised at how much feel you will get by making the arc with the hub "by hand " any signs of "nipping up" will be much easier to spot .
This is really to make sure the joint at the chassis end has as much travel as the movement of the damper , if the damper moves more it will act against the comp stut in the TCA and i reckon it'll contibute to snapping bolts or twisting struts etc...

 

cool, thanks for that. ill give it a go when i next get chance to work on the car

 

I suggested that might be a problem back in this thread but not so eloquently!

https://passionford.com/forum/genera...e-aware-3.html

 

Anyone who uses anything other than a proper 12.9 spec or above in such an important area, really needs their head looked at.

 

as above-when i prep rally cars i convert all suspension bolts to 12.9 grade bolts and the correct torque setting,never had any fail yet