Knock knock knocking

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Knock knock knocking

Postby burnzdog » 06 Jan 2020, 15:02

Hello and happy new year to all!

Now, onto less happier business. To cut a long story short after having had the front diff out (which was sent to aidan in wales for a checkup - all clear) and put back in and front axles replaced I still have a a knoch coming from the front. I did a round trip of 300 miles over christmas and it appears to be getting worse. I cannot pinpoint where its coming from and I have tried to isolate by relacing things and checkign and re-checking. I bought a complete axle so that I could take both exisitng out of the equasion but its not that. At the weekend i took out the front moutns checked cleaned and reseated. Didnt help.

I after any advice, or someone nearby that would cast there eye over the van. As im at a loss with this.

Thanks

Matt
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Re: Knock knock knocking

Postby silverbullet » 06 Jan 2020, 19:33

Knocks and vibrations rarely originate from where you think you can hear them on a syncro!
Start with the last thing you touched or loosened and work back from there.
Btw I had an intermittent wooden sounding knock that I couldn't trace: turned out to be a broken grille clip at the driver's side top corner, it let the grille flap when picking up turbulence following certain vehicles...

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Re: Knock knock knocking

Postby burnzdog » 06 Jan 2020, 20:19

Problem is so much has been changed now it's hard to know when then problem was introduced. All I know is alot has come in and out. The knocking is definitely central though, whether that's the source I don't know, but it definitely manifests centrally above the diff.
silverbullet wrote:Knocks and vibrations rarely originate from where you think you can hear them on a syncro!
Start with the last thing you touched or loosened and work back from there.
Btw I had an intermittent wooden sounding knock that I couldn't trace: turned out to be a broken grille clip at the driver's side top corner, it let the grille flap when picking up turbulence following certain vehicles...

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Re: Knock knock knocking

Postby silverbullet » 06 Jan 2020, 21:59

New propshaft or recycled? Front driveshaft spacers fitted with correct length bolts?

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Re: Knock knock knocking

Postby Jim San » 06 Jan 2020, 22:03

I had a upper wishbone bolt lose once - that sounded like it was underneath.
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Re: Knock knock knocking

Postby burnzdog » 06 Jan 2020, 22:10

Propshaft hasn't been changed the two front axles, one is completely new so that I could swap out all combinations so that I could discount a single axle being the problem.

When you say driveshaft spacers do you mean spacers connecting between diff and CV joint?


quote="silverbullet"]New propshaft or recycled? Front driveshaft spacers fitted with correct length bolts?

Sent from my S60 using Tapatalk[/quote]
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Re: Knock knock knocking

Postby burnzdog » 06 Jan 2020, 22:17

Hmmm interesting you should say that. I have spacers on the upper wish bone joints. One of the bolts feels like it won't tighten fully.

When you say bolt you are talking about the 2 bolts the screw into joint?

Jim San wrote:I had a upper wishbone bolt lose once - that sounded like it was underneath.
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Re: Knock knock knocking

Postby Jim San » 06 Jan 2020, 23:43

burnzdog wrote:Hmmm interesting you should say that. I have spacers on the upper wish bone joints. One of the bolts feels like it won't tighten fully.

When you say bolt you are talking about the 2 bolts the screw into joint?

Jim San wrote:I had a upper wishbone bolt lose once - that sounded like it was underneath.



I have spacers also, thankfully they are fine.
I mean the large single bolt that joins it to the chassis. It had been for alignment in the months prior and not secured properly.
I was convinced it was under the gearstick sort of area (still have slips of cardboard wedged in places to try and determine where ) but once jacked up the fault was found in seconds.
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Re: Knock knock knocking

Postby jaber » 10 Jan 2020, 22:01

Broken spring, a shock may have gone hard? I had one go hard on the back he’ll of a knock over even small pot hole

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Re: Knock knock knocking

Postby burnzdog » 15 Apr 2020, 10:44

Finally found it. The upper wishbone was too tight by looks of it. Loosened off to recommended torque and no more knocking.
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