Technical Lnocking noise no load.

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Technical Lnocking noise no load.

bozzy

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Knocking noise no load.

After a faultless day yesterday at Gaydon my JTD has developed a loud knocking noise at what seems the centre of the engine bay. It sounds almost rotary but only noticeable when the clutch is in or coasting in neutral.

Search shows too many possibilities so if anyone has any ideas then any help would be appreciated.

At speed it's not there, as I roll to a halt clutch in and knock, knock, knock.
 
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bozzy

bozzy

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Somebody suggested the auxiliary pully? anybody know where to look for such a device?

H2DaE believes it's a common fault on the JTD but I have never heard of it.
 

Deckchair5

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I presume they meant your aux drive pulley. I can't imagine the drive pulley itself causing noise problems as it's bolted directly to the crankshaft but the belt tensioners might
jtd aux drive.JPG
 
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bozzy

bozzy

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Ah I see, it happens when the car is stationary too?

No, fine when stationary or under power. If I ease off the gas it happens, if I put it in neutral and roll it happens. Clutch in and roll it happens. It's only when it's not under load it happens. So frustrating but I shall get the dealer to look at it Friday.
 

LoBsTeR

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I would say that it's not the aux drive pulley then. This pulley turns constantly whether you are stationary or moving. If it was loose then you would hear the knocking stationary and moving.

Definately sounds like a cv joint to me.

No big deal really but get it sorted quickly possible as you dont want to cause any damage to the gearbox oil seals.
 

ABZSTILO

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CV joint is a distinct possibility, could also be the thrust bearing on the clutch (had a few of those make some noise in my time) or God forbid something starting to go in the gearbox :eek:

Roll on Friday :chin:
 

Deckchair5

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Yes if it's only happening when you're moving then that's rolling gear so could well be CV joints. Especially if you've lowered it as that puts all the CV joints out of line and even more so if it's remapped as that's more load again
I have a feeling Bozzy would have done both:)

driveshaft 1.JPG

Outer CV joints (in the wheels) tend to produce "knock on lock" so it's not them but could well be inner CV joints (next to gearbox). Stick it in gear and try to rotate the driveshafts by hand both ways. Get lots of movement and a big clonk? There's your play

Clutch bearings will usually make noise when stationary if you're just on the bite- sometimes scream- sometimes grind- and tend to rattle with clutch up in neutral
 
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PNL

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Yes if it's only happening when you're moving then that's rolling gear so could well be CV joints. Especially if you've lowered it as that puts all the CV joints out of line and even more so if it's remapped as that's more load again
I have a feeling Bozzy would have done both:)

View attachment 33025

Outer CV joints (in the wheels) tend to produce "knock on lock" so it's not them but could well be inner CV joints (next to gearbox). Stick it in gear and try to rotate the driveshafts by hand both ways. Get lots of movement and a big clonk? There's your play

Clutch bearings will usually make noise when stationary if you're just on the bite- sometimes scream- sometimes grind- and tend to rattle with clutch up in neutral

If you read boz's post again it says he gets it only when coasting or the clutch is in and I gather [from what I am told ]the diffs can be a problem on the jtd's Dans was knocking when he sold it on so I think this could be where the problem is comming from.. inner joint would be included in this as well as they locate into the diff ..
 
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LoBsTeR

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I hope it is the CV joint.

If it was the diff, would it not do the same thing under load?
 
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bozzy

bozzy

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I hope its nothing but will settle for a CV joint. Thing is going to the dealers like going to the doctor, always a misdiagnosis. Go in with a broken leg and they tell you it's a virus.
 
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bozzy

bozzy

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Dealer just called to say drop-links. I collect it later so will let you all know if the diagnosis is correct. Sounds a bit iffy but if he's right I will praise the man.

£175.00 though
 

Deckchair5

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Drop links? I would take your shot gun with you. Won't make any difference whether the clutch is in or out if it's drop links as they just connect the car body to the anti roll bar and will make no difference whether you're in gear/ out of gear/ clutch in or out

Drop links produce more of a constant rattling noise on rough surfaces but are noticeably dead quiet on smooth surfaces as the suspension doesn't move

This doesn't sound good

So it's either shoot the tech or shoot Bozzy's noise description:)
 
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PNL

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Drop links? I would take your shot gun with you. Won't make any difference whether the clutch is in or out if it's drop links as they just connect the car body to the anti roll bar and will make dno difference whether you're in gear/ out of gear/ clutch in or out

Drop links produce more of a rattle on rough surfaces but are noticeably dead quiet on smooth surfaces

This doesn't sound good

They taking the pee which baseball bat do you want Decks :bang:
 
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