Upper arm loosening

Post by **NafemanNathan** » Wed Feb 15, 2012 11:11 pm

After fitting my replacement NS front upper arm assembly the other day, just today I noticed a rattling noise had come back. Turned out there was play coming from both bushes of said arm.

When I got the assembly, both nuts on each of the two bushes were loose and there was loads of play because it was evident I had to tighten the nuts to clamp down on the bushes. Although obviously I wasn't to clamp them too tight as the bushes still needed to rotate in the arm. Only thing was, I noticed the nuts supplied weren't locking nuts, so I imagined they could easily work loose. I compared it to the original arm assembly and they were plain nuts to, so I thought the new plain nuts must be fine to use.

In theory the nuts with the bolts are free to turn together, so if the bush caused the bolt to turn the nut could turn with it meaning it wouldn't loosen, but in practise the nuts are obviously the reason the bushes are now loose (Although I've tightened them up again for now).

Has anyone else had problems after fitting new upper arms, or did you use nylocs or threadlock etc?

I'm going to pick up some nylocs from work tomorrow and swap them over just in case. It may have just been a case they needed to settle in, but still.

Post by **Vtecmec** » Thu Feb 16, 2012 8:50 am

NafemanNathan wrote:Although obviously I wasn't to clamp them too tight as the bushes still needed to rotate in the arm.

Are you using poly bushes? I ask because the rubber ones are not supposed to rotate.

Post by **NafemanNathan** » Thu Feb 16, 2012 9:25 am

No, not polybushed. But sorry I worded that wrong... But you having asked that now it's suddenly just clicked that maybe I should have clamped the nuts down as tight as possible, pinching the metal inserts inside the rubber bushes, as when the suspension flexes it literally just twists the rubber bushes in their casings. Is that right

It didn't seem right when I did it, but I had only tightened the nuts enough to clamp down on the metal insert, enough to remove any play on the bush, but so that the bush could still rotate quite freely. That was wrong wasn't it?

There's nothing I could see in the manual as it just treats the whole thing as an assembly that you're not supposed to dismantle.

Post by **Vtecmec** » Thu Feb 16, 2012 9:41 am

You're spot on, they need fully tightening and any movement occurs in the flex of the rubber. When I do mine, I'm going to torque them to the same value as the ARB's.

It also means that ideally the car should be sat at driving level and not jacked up when they are tightened, so they get tightened at their 'rest' location.

Post by **NafemanNathan** » Thu Feb 16, 2012 9:47 am

Cheers bud. That all makes perfect sense now. Glad I asked

And yep, I tightened them up last night whilst the car was sat on the ground

Post by **vanzep** » Thu Feb 16, 2012 9:55 am

I posted up a similar question on puk a couple of weeks ago - before fitting my polybushed wishbones - i did tighten them up before fitting but i have noticed a rattle on one side and was going to look at it today - sounds like i should get some nyloc nuts and tighten them up when car is sat on level ground like youve done Nathan.

Post by **NafemanNathan** » Thu Feb 16, 2012 10:15 am

Fingers crossed I won't need the nylocs now Nick. As the arm is compressed so much once the nuts are tightened fully, it should act like a spring washer and mean the nuts won't come loose. It'll be a pain in the butt to thread nylocs on whilst it's still on the car anyway

And at least it gives a good amount of warning as even if it's slightly loose it lets itself be heard, so I think I'll stick with the plain nuts and just see how it goes

Definitely likely to be the cause of your rattle though if you didn't tighten them up though

Post by **Vtecmec** » Thu Feb 16, 2012 10:41 am

.

vanzep wrote:sounds like i should get some nyloc nuts and tighten them up when car is sat on level ground like youve done Nathan.

If your bushes are poly, then there is no need to level the car before tightening, as they work by rotating around the central shaft, and so will align themselves automatically.

Post by **vanzep** » Fri Feb 17, 2012 4:18 pm

cool - will tighten them up a bit more when i put the konis on (tomorrow - weather permitting)

Post by **vanzep** » Mon Feb 20, 2012 11:00 pm

hmmm
still got a bit of chatter at full lock - its not too bad - i checked the wishbones at the weekend and theyre well bolted down - i cant have over tightened the polybushes could i ?
might check the arb as well