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Old 17th November 2016, 05:43   #11
T16
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Hmm...

Im concerned I may have cross threaded the rear damper bolt...

Maybe I am just being paranoid, but it was NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD- stiff to tighten, and looking at the end of the bolt from the outside where you see the end of it poking through the hole to the outside of the car, it doesnt look quite central. Surely if I had cross threaded such an enormous M12 thread, there would be huge bits of swarf everywhere? It was tight, and I would back it out checking the bolt, and I couldnt see any damage to the threads on the bolt. Just concerned why it was so tight. Maybe the person before me damage the thread somehow. I am usually ultra careful. After tightning it up (nipping it) I then swapped the bolt from the other side, and this one seemed to turn freely. Maybe it was just the first couple of threads on the bolt that were damaged? Two new springs are in at least.


I'll take some pics....

Last edited by T16; 17th November 2016 at 05:46..
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Old 17th November 2016, 09:35   #12
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Quote:
Originally Posted by T16 View Post
Hmm...

Im concerned I may have cross threaded the rear damper bolt...

Maybe I am just being paranoid, but it was NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD- stiff to tighten, and looking at the end of the bolt from the outside where you see the end of it poking through the hole to the outside of the car, it doesnt look quite central. Surely if I had cross threaded such an enormous M12 thread, there would be huge bits of swarf everywhere? It was tight, and I would back it out checking the bolt, and I couldnt see any damage to the threads on the bolt. Just concerned why it was so tight. Maybe the person before me damage the thread somehow. I am usually ultra careful. After tightning it up (nipping it) I then swapped the bolt from the other side, and this one seemed to turn freely. Maybe it was just the first couple of threads on the bolt that were damaged? Two new springs are in at least.


I'll take some pics....
Ross - good work.

I seem to remember my damper bolts being pretty stiff even on replacement- I think the factory had put some Loctite on the threads - perhaps if this is not cleaned off fully before replacement, the bolt will still be stiff. Wire brush the threads before replacing them. If you have cross-threaded it, there will be swarf and visible damage to the thread when you remove it. You can try running a die down the bolt thread and a tap into the bolt hole, if you have a tap/die set - this should sort it out.

Put a picture up if you can.

Cheers

Pete
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Old 17th November 2016, 12:44   #13
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I took some pics, hope I have not screwed this. Ive lost confidence with cars since my father died. See how in the middle pic the bolt head looks off to the side a little? The very first thread on the bolt is definitely damaged, but the rest look ok. To me it looks like its sitting at a very very slight angle, but it could be my eyes! Surely to god on such a course thread, if it was crossed, the angle would be rather obvious? There were a couple of very very tiny specs of metal, but no fragments. Im hoping my action of running the bolt through was the filth and dirt that was in the hole being pushed through....The bolt from the other side ran through no problem afterwards, and torquing it up to 150nm and then removing it again, there was no issue at all. Maybe it was just that first thread on the other bolt that was a problem? Any thoughts on the below pics welcome:-






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Old 17th November 2016, 22:45   #14
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Anyone?! :p
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Old 17th November 2016, 23:45   #15
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I cannot tell from the pictures, nor have I had direct experience working with these bolts, however, I have had some experience with some bolts lol (some nuts too, but thats a different story lol).

As mentioned, threadlock, which looks like it has, will make the bolt feel tight. Another thing I have noticed in the past particularly with large bolts, is when looking at the end of the thread, it can sometimes make it look like it is off centre.

Again as mentioned before too, running a tap and die on the threads will be useful. If they run through relatively easily, then you will know it isnt threaded. It will be a little firmer running over the bolt at first because of the threadlock, which it will remove, so having a small tube will be beneficial. Lidl in NI recently had a tap and die set in their offers. I have only used it to tidy up my spare caliper bolts and carriers. It worked rather well for £7.99. Not sure if it will have the set you would need, but it would be worth buying a tap and die for the size you need for that peace of mind? LINK for reference
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Old 18th November 2016, 01:31   #16
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OK thanks!

Hopefully a resident engineer can see those pics and comment on the thread in the pics....

Again, I do wonder on a bolt so large, and on a thread so course, is it even possible to have a damaged thread that can offset the bolt by a fraction of a mm....?

Like I said the first thread on the original bolt was a little rounded compared to the rest of the bolt. Only the first thread... Maybe winding that through as caused a problem? Im so paranoid and stressed at the moment, this is what happens when you work on the car at 3am under pressure to fix it asap.

Of course working under the car with little room amplifies the effort needed to wind the bolt in, I was using a 10" bar to turn it. It was very very tight, but if I immediatly wound it back, it was perfectly smooth again.

If I had genuinely cross-threaded it, surely the angle would be obvious? So Im trying to work out if the actual hole from the factory is not thousandth perfect, or whether I have done something bad.
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Old 18th November 2016, 05:17   #17
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There is no chance you could get a bolt that big, that far through if it was threaded. It would have started spinning before it got that far.

Not sure why you are concerned if you managed to torque it up ok.

One thing i have experienced with this particular bolt is that some of the new bolts rimmers supplied bottomed out on the shoulder before the shock absorber was tight, so the washer could be spun with the bolt tight in the hole. I added an additional washer to resolve it, but was a bit frustrating at the time, and i thought at first that it was just tight.
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Old 18th November 2016, 06:28   #18
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There is no chance you could get a bolt that big, that far through if it was threaded. It would have started spinning before it got that far.

Not sure why you are concerned if you managed to torque it up ok.

One thing i have experienced with this particular bolt is that some of the new bolts rimmers supplied bottomed out on the shoulder before the shock absorber was tight, so the washer could be spun with the bolt tight in the hole. I added an additional washer to resolve it, but was a bit frustrating at the time, and i thought at first that it was just tight.
What made me paranoid was after just a few turns, the bolt went super tight, despite everything "Looking" like it was ok. Because I was tired, cold, and pushing myself harder than I should at my age, I just carried on assuming that it was just dirt. I needed a lot of force to wind it in. I guess if I had really NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD-NAUGHTY WORD- it, there would have been a sort of defining thunk, as it knackered the thread in the trailing arm.

Still, hopefully it was just dirt and threadlock which made it so tight, the corrosion in the hole was quite bad.

I think you might be right, a thread that size, if it was properly crossed, I would either wreck it with lots of swarf, or, it would just seize solid and I wouldnt have the strength to go any further. What is it.. M12 x 1.5 maybe?

Thanks to all who replied, Ive been studying 16hrs a day, looking for a new apartment and other things, and it really messes with your head when you are working on burnout.

Normally these things would be a doddle, but for some reason everything related to the car is one big headache at the moment.
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Old 18th November 2016, 16:06   #19
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I think you are worrying too much - from what I can see on the photographs all is well.

Have a good sleep and things will look better afterwards.
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Old 18th November 2016, 16:15   #20
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Quote:
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I think you are worrying too much - from what I can see on the photographs all is well.

Have a good sleep and things will look better afterwards.
I second that - it is always better to work on our cars when you are fresh, relaxed and not under time pressure. I am pretty sure the blue locking compound on these bolts is what makes them seem a struggle to replace - I cannot see any obvious evidence of cross-threading on the pictures or from what you have said.

Have a good weekend

Pete
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