at idle clutch has knocking sound

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seanboy
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Wed Oct 01, 2008 6:25 pm

After taking my 325i manual out for a spin and when parked up left to idle before turning her off I get a knocking noise? If I press the clutch pedal down while at idle (not engaging gear) this Knocking noise stops. I also seem to have a small oil leak coming from that area, Will have to jack her up and have a look at this little leak! anyone got any ideas about the knocking noise?
Cheers Sean.
bss325i
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Wed Oct 01, 2008 6:28 pm

The noise is normal.
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uzdubmwe30
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Wed Oct 01, 2008 6:34 pm

Gearbox sounds a little worn fella. Or it could be thrust washers on the crank, but I doubt it.
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Omi
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Wed Oct 01, 2008 6:40 pm

Leak from either end of the box is common and isn't a great worry unless it's getting near clutch friction surfaces, or leaving you without sufficient lubrication. Your noise is consistent with layshaft bearings, in most cases.

Bear in mind when you are in neutral without clutch pressed, your input shaft is still turning with the crank, as well as the layshafts in the gearbox... When you press the clutch pedal, the engine is disconnected completely from the box and you can hear these bearings wheeze to a standstill.

In gear, the slack on these bearings is taken out so wouldn't make a noise.

Not the end of the world, but the leak and this wear implies your gearbox may be old, worn and may not have been looked after. - Keep your eyes out for a cheapie low-miler and swap 'em out next time you need a clutch or if the worst happens. :)
...or is it?
oakey
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Wed Oct 01, 2008 7:02 pm

bss325i wrote:The noise is normal.
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seanboy
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Wed Oct 01, 2008 7:34 pm

Sound lads, Cheers for the quick replies. Still got a good strong clutch at the moment :wink:
Cheers Sean.
d6dph
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Wed Oct 01, 2008 7:54 pm

Mine has done this since I bought it (3 years ago), Still works perfectly so I'm not stressing :D
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Omi
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Thu Oct 02, 2008 8:26 am

Mine does it too. Not saying it's about to explode. - Just what the fault is to cause the noise.

It is NOT normal, though. - New gearboxes don't do this, and neither did yours before it had 20 years and 100,000 miles of wear put on it.
...or is it?
bss325i
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Thu Oct 02, 2008 10:55 pm

Mine has only done 50000 miles and has had regular oil changes. It had done it all the time i have had the car and i bought it with 32000 miles.

I've not heard a getrag 260 box not do it.
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