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Old 24th June 2021, 12:37   #1
Retap
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Default ZTT NS front clunckety clunk

So Nigel my CDTi ZTT mk2 got severely potholed just after Christmas breaking the rear NS spring and destroyed the front NS tyre side wall with the very same wheel having a new bearing months before that for MOT. Before then last summer the trailing arm and bush was new so a bit miffed tbh with this noise and yeah very prepared to find the ball joint of the trailing arm loose but no wheel play detected yet. Council paid out for tyre eventually but really wish had got recovered proper on the day and had a garage look at it properly because there is this clunk since then and i dont like it.

I would welcome suggestions on what to look at because ever since the pothole event there is the clunk from the NS front that sounds like the trailing arm ball joint is loose or maybe even shock/spring related but when i push down on NS wing and bounce it a bit there is no noise. I keep checking for wheel play because of the clunk sound whilst driving from that side, it gives me the willys but its just noise no vibration only present when the NS wheel is presented with rough road which seems to be to often these days.

Have spent a bit on this car prob more than i would care to mention and its probly time to do front springs now but could have bought two more cars for what ive forked on putting it right so far lol but a good drive none the less.

After last MOT a few months before the pothole had to have new rear upper arm and spring on OS and after the pothole the NS rear upper arm and spring got done out of necessity so the back of the car is solid now.

Since last summer the front suspension arms and bushes where replaced along with inner and outer tie rods so the car drives straight and true its nice to drive other than this mild clunk on from the NS front post pot hole.

If i park the car up and rock it gently by holding the roof above front windows there is clunk sound from the ns front area its not overly metallic more lick a thud clunk sound but i dont get how theres no wheel play as last time my trailing arm was loose it sounded very similar and there was wheel play. Could it be that gear box engine mount after such a pot hole shock?

Any ideas welcome im going out later to jack it up and take a big bar to the trailing arm to check it for play and that.

Cheers and sorry to go on....
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Last edited by Retap; 24th June 2021 at 12:39..
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Old 24th June 2021, 15:41   #2
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Default Suspect NS Damper

So just been out to have a good look over Nigel and found no wheel play at all even with a big bar but did discover that with the car jacked up from the front using the sub frame on almost level ground that the NS wheel is sitting about 2 inches higher than the OS wheel. However on level ground when down the car is level. I do not know if the difference in wheel height whilst raised is normal but i suspect not, could anybody confirm


Also apologies for the state of the wheels and the springs its obvious the springs are ready for change but the wheel will soldier on for now.


See the photo below I used a piece of card to measure distannce from the rim edge to the arch edge.










Photos of suspect shock NS



















ITs time to do front shocks and springs, anybody interested in some work cash job?
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Last edited by Retap; 24th June 2021 at 15:56..
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Old 24th June 2021, 15:47   #3
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I like the effort with the photo.

Are you sure you don't have a snapped spring? If it snaps off at the end and the spring is still sitting in its cup, sometimes you need to get your nose right in there to notice.
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Old 24th June 2021, 15:58   #4
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Quote:
Originally Posted by AndrewJames View Post
I like the effort with the photo.

Are you sure you don't have a snapped spring? If it snaps off at the end and the spring is still sitting in its cup, sometimes you need to get your nose right in there to notice.



Thanks im a bit OCD like that, mechanical engineering isnt my primary forte but give me some silicon and your on lol.



Its a good shout i have little experience with springs n dampers but i did have a good look and can see nothing snapped. I counted the spring coils visible and both sides are the same having three spring coils visible coming down so if it is snapped it will be way up out of view like you say. I suppose i should consider myself fortunate if snapped it did it way up but i dont know but looking at the state of the springs would say highly probable.


EDIT


Whilst up i gave the troubling wheel a few good pushes down and couldnt move it plus no sounds like scraping spring n such??
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Last edited by Retap; 24th June 2021 at 16:10..
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Old 24th June 2021, 16:07   #5
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Quote:
Originally Posted by AndrewJames View Post
I like the effort with the photo.

Are you sure you don't have a snapped spring? If it snaps off at the end and the spring is still sitting in its cup, sometimes you need to get your nose right in there to notice.



Best photos I have looking up:





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Old 24th June 2021, 16:24   #6
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I didn't realise there was more than one photo. My brain may be playing tricks on me but I only saw the one with the cardboard lol.

If a spring breaks it's more likely to break at the bottom on the last coil or two. Where the bottom of the spring sits (I said cup but probably should have said seat?). It will often be broken around the back of the spring so it is difficult to notice on first glance.

If it's not broken I guess you could have mismatched springs, or just old and tired springs.

Suppose you could have a strut/shock problem too but I'd be surprised if that would have you generating a clunking noise just by rocking the roof of your car by hand (I think you wrote that. Apologies if not.)

Anyway, I'm not a mechanic so I'll step aside and perhaps someone with more knowledge can step in and advise you
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Old 24th June 2021, 16:36   #7
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Quote:
Originally Posted by AndrewJames View Post
I didn't realise there was more than one photo. My brain may be playing tricks on me but I only saw the one with the cardboard lol.

If a spring breaks it's more likely to break at the bottom on the last coil or two. Where the bottom of the spring sits (I said cup but probably should have said seat?). It will often be broken around the back of the spring so it is difficult to notice on first glance.

If it's not broken I guess you could have mismatched springs, or just old and tired springs.

Suppose you could have a strut/shock problem too but I'd be surprised if that would have you generating a clunking noise just by rocking the roof of your car by hand (I think you wrote that. Apologies if not.)

Anyway, I'm not a mechanic so I'll step aside and perhaps someone with more knowledge can step in and advise you

Hi and thanks for your reply, apologies i was still filling out the post in edit adding the photos to finish as you replied.


Cheers.
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Old 24th June 2021, 17:44   #8
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There is the rare possibility that when hitting the pothole the N/S shocker piston rod has been bent and the bent section is preventing the shocker from reaching its maximum amount of downward travel.


If it was a deep pothole the shocker may have been fully extended as the wheel dropped in the hole and when the wheel contacted the edge of the hole it both bent the piston rod and as the weight of the car was again pushing the rod back down into the shocker, the bent section could have been forced into the shocker, but won't come back out again under spring pressure.


There aren't many other things that will prevent a shocker from reaching its maximum extension when a wheel is off the ground.


Annoyingly the only way to prove this is to remove the leg and spring.
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Old 24th June 2021, 18:52   #9
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Quote:
Originally Posted by Ducati750cc View Post
There is the rare possibility that when hitting the pothole the N/S shocker piston rod has been bent and the bent section is preventing the shocker from reaching its maximum amount of downward travel.


If it was a deep pothole the shocker may have been fully extended as the wheel dropped in the hole and when the wheel contacted the edge of the hole it both bent the piston rod and as the weight of the car was again pushing the rod back down into the shocker, the bent section could have been forced into the shocker, but won't come back out again under spring pressure.


There aren't many other things that will prevent a shocker from reaching its maximum extension when a wheel is off the ground.


Annoyingly the only way to prove this is to remove the leg and spring.

Great point thanks it sounds reasonable to me and the pothole was a bad one ankle deep it was. after changing the wheel i popped the bonnet to check the strut top thats how bad it was!



love ya sig!
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Last edited by Retap; 24th June 2021 at 18:55..
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Old 24th June 2021, 19:47   #10
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ooow im all in doesnt look to bad so shopping for spring compressors lol


Note to self post 7: https://the75andztclub.co.uk/forum/s...d.php?t=102722
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