Snapped upper wish bone bolt

[normspanners]

actually the first time it loosened then i tightened it up would have had a similar effect to me loosening it off then droping the weight onto the wheels! anyway why dont they come with destrustions like you said

BUT you had already worn the gripping serrations on the bush at that point by running it slack so the grip after tightening it was not there, to combat the braking twist,------ until you got the (click but I'll keep pushing to make sure its tight) torque wrench on it
then it was proper tight !!! -----you could see that easily coz the end of the threaded pin was in your hand.

 

[normspanners]

Yes, but if did you overtorque it when you did it back up because it had come loose?

Once you've stretched the bolt it's downhill from there.

He didnt overtighten it, coz he used a torque wrench---------

ok so the nuts either end of my new upper wish bones keep loosening by themselves well one each side.

I am thinking the nylocks are crap and not doing there job

but it is too late for one side now as I tried to tighten it again and snapped it.

---------- until he sheared it off

 

[bricol]

As explained, the moment created by the braking isn't doing what you think - it's the pure simple movement of the suspension arm up and down, whether that's weight transfer under braking or simple suspension movement. Now if we were talking about the rear bolt holding the pivot bar, the broken bit here, stretching and failing to the chassis leg, then you might have a point.

Hopefully the replacements, fitted loose, dropped on the floor, or arm jacked up to take the weight of the car (with the car adequately supported elsewhere) and torqued to the correct figure ;-) will be fine.

 

[123hotchef]

I only have 1 replacement I hope the other side will be ok

 

[Wozzaaah]

I only have 1 replacement I hope the other side will be ok

Cue another 105 posts to ascertain why the second one keeps coming loose.
I can't believe it took all that to find out you'd fitted them incorrectly when you were adamant you hadn't!
As they say....honesty is the best policy.

 

[123hotchef]

I though that being as I could move them in the vice it would be just fine but obvisoly I was wrong lesson learned ask on here first next time

 

[normspanners]

As explained, the moment created by the braking isn't doing what you think

Believe me it is, because under braking the wish bones will try to spread open, albeit only slightly putting strain on its fasteners, I watch it intimately every day under cars with the mot wheel play detectors, and it surprises a lot of people just how much bushes and arms move, and braking force is considerably more violent especially braking a 2.5 ton pick up, trailer and horses, the forces are immense.
On the near side the wish bone will want to turn forward with the wheel, putting more strain onto the front fastener especially, the one that was sheared and the one that was from reading his script the one that moved the most, hence it was the one that snapped whilst trying to overtighten it.

 

[normspanners]

Cue another 105 posts to ascertain why the second one keeps coming loose.
I can't believe it took all that to find out you'd fitted them incorrectly when you were adamant you hadn't!
As they say....honesty is the best policy.

Least we (maybe) sorted the issue, dont be too harsh on him sometimes it is all too easy to get confused as to what has an did happen especially typing it out I know I write sumat down then proof read it after I posted and realise I (well my fingers) had not written what my brain was writing and it sounds complete dross when proof read.
edit... Like just now, a comma in the wrong place can change a meaning completely

 

[normspanners]

Yes but they were loosened by the action of the bush, they didn't carry on unscrewing and fall off the end of the bolt did they?

only to the point that the bush/ wishbone normal physical spreading allowed, a further heavier emergency braking session would have moved it further.

 

[Wozzaaah]

Least we (maybe) sorted the issue, dont be too harsh on him sometimes it is all too easy to get confused as to what has an did happen especially typing it out I know I write sumat down then proof read it after I posted and realise I (well my fingers) had not written what my brain was writing and it sounds complete dross when proof read.
edit... Like just now, a comma in the wrong place can change a meaning completely

I'm just teasing but we did (as we say down here) go all round Bristol to get to Bath,

 

[123hotchef]

well i have fitted the replacement NS and it all seems good now the serations had worn smooth.

I also checked the OS and ending up changing that back to the old wishbone as the thread was fooked and I could not repair it

 

[PhillipM]

Torque wrench only goes to 11, eh?

 

[colnerov]

He's got the touch of a rapist with a torque wrench.

 

[8ob]

Bit like a cow with a gun

Bob

 

[123hotchef]

I may be able to use a die on the threads who knows

 

[daedalusminos]

out of interest, what torque did you tighten them to that caused them to break/strip? Or did you tighten to 100lb.ft + 1/2 turn?

 

[123hotchef]

130nm initially then FT

 

[123hotchef]

do you think a m14 die would repair the thread I cant start the nut properly and have tried filing the start of it down for ages to no avail

 

[PhillipM]

Not if you've stretched it, no. If you've just dinged the very first thread or similar, yes, but filing should have fixed that.

 

[123hotchef]

doh!