Knocking noise from rear

ignat

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I have an annoying knocking sound coming from the rear of the LC.

It happens whenever I go over some bumps - even manhole covers cause it. It is more pronounced at the near side but has started to develop on the OS too.

Sounded at first like it was the bottle jack loose in its holding place. Eliminated that, then thought it might be the stabiliser drop links. Replaced both of those and still the knocking persists.

I have recently replaced all shocks and had a full set of polybushes fitted, which hasnt stopped the knocking.

Considered the body mounts but it appears they are in good nick. Although I'm thinking replacing these is my last resort.

Any ideas?
 

Paul

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Exhaust? Maybe a good swing on it to check.
 

Chris

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Kevin, have you had the rear radius arms rebushed? That's a known knocking point. They wear quite badly. Doesn't need much movement for then to knock. Anti roll tends not to knock. Are all the damper mounts tight? The top mount is a devil and might not be fully tight.

Could be a prop, but unlikely. Wouldn't be body mounts in my view.

Chris
 

ignat

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hmm ok that gives me some things to look at.

Mechanic said exhaust was fine. I will double check though. Radius arms were done - was a full SuperPro kit. Damper mounts? Well the noise was there before and after I had OME put in. So I guess they are tight.

Doesnt sound like its very far back near the wheels. Seems to come from underneath the back seat area
 
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Chris

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OK, I would pull the rear radius arm bolts (by back door) and check to see that the oles that the bolts go through are not slotted. They tend to wear and then the new bush slams back and forth in the slot. Only a couple of mm but it will give a thump and bang. Repair plate can be welded over the hole either side.

Chris
 

Andrew Prince

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I second what Paul and Chris have said. Another question - it's not some of the tupperware that 90s have underneath flapping loose/cracked?

Exhaust hanger still sounds like the leading candidate to me, seeing as your bushes have just been done.
 

ignat

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Tupperware such as..?

There were a couple bolts sheared off the fuel tank bashplate. Someone in the past has tried getting it off. Sorted that and still no joy.

Definitely sounds like a metal-on-metal thud/knock. :cry:

I'm hoping its the exhaust mounts. Dont think i will be checking tonight though, the Walkabout is calling :)
 

Chris

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Sounds really really like slotted mounting holes.

Chris
 

Andrew Prince

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I thought there are/were a bunch of plastic "bashplates" underneath? One of those coming loose or cracking

Walkabout on a school night??? You must be having a rough start to the week :lol:
 

Andrew Prince

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Chris said:
Sounds really really like slotted mounting holes.

Chris
Chris, weren't you adamant that you didn't have this problem on Lil Blue with the same symptoms? Until you discovered that it was this problem :?: :lol: :lol:
 

Chris

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Errrr, no.

Not how I remember it. I discovered the answer I believe, Andrew. Don't recall anyone offering that as a solution. Everyone just kept telling me it was the bloody exhaust knocking! I thought that the arms might be loose or perhaps worn inside, but once I had fixed that and the noise continued - but not as badly, I knew that I had made some change worth investigating further. It was only on closer inspection that I found the elliptical nonsense.

Chris
 

Chris

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Wot - we married now or sumfink? That's her job.

OT Nipped out yesterday, came back and she'd gone out, locked the house and taken my car! Well at least the dog got another walk. Now that's how to wind me up.


Chris
 

Ecky Thump

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Chris said:
Wot - we married now or sumfink? That's her job.

OT Nipped out yesterday, came back and she'd gone out, locked the house and taken my car! Well at least the dog got another walk. Now that's how to wind me up.


Chris

My missus hasn't sussed out my isolating switch yet :twisted:

It's mine, all mine :lol:
 

Chris

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Nah, she took the Verso. With no fuel in it! Was thinking, there'll be a call any minute. 'It's stopped'. Then I remembered that I didn't have my phone with me.

All well, come on dog. Walkies.


C
 

BobMurphy

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Mine used to clonk on manhole covers and suchlike. I found that the O/S rear spring had broken.

All is sweetness and light now I've replaced all rear bushes, springs and shocks.

Bob.
 

BlackWidow

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Kevin,

Have you still got the rear, rear seats in? If you have take them out and see if the noise goes then. If it does I will tell how long it took me to find my rear knocking noise :oops: :oops:

Steve
 

ignat

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Well thats the noise sorted..

It turned out to be my.....ROOF RACK! :oops:

Three people sat in the back, all three of us (two of them mechanics) were adamant this came from the bottom of the vehicle.

Well before I got to checking the mounting holes I needed to remove the rack to get into an underground parking lot - and magically the noise disappeared. Roofrack was not 100% tight

Must be one of those weird properties of sound waves that caused us to think it was coming from the chassis area :roll:

Now if I can only get this snorkel rattle sorted ... :evil:
 

DaveWall

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Did you mention Snorkle Rattle..... I have been mucking about with foam... sound deadening.... bushes on the air box etc etc etc to try get rid of a snorkle related vibration at about 1900 rpm for ages now (currently driving my old Hi-Lux, so that my temper doesn't start getting involved - Hammer nearly came out the other day)

Dave
 

ignat

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DaveWall said:
Did you mention Snorkle Rattle..... I have been mucking about with foam... sound deadening.... bushes on the air box etc etc etc to try get rid of a snorkle related vibration at about 1900 rpm for ages now (currently driving my old Hi-Lux, so that my temper doesn't start getting involved - Hammer nearly came out the other day)

Dave

1900rpm? My rattle was exactly at 1900 :lol:

Got that sorted but now another rattle has started . sounds like a bag of nails -really annoying . hope to have a closer look tomorrow

:roll:
 
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