low drone/humming

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Barton
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Sun Feb 13, 2011 11:19 am

recently my car has developed a low drone / humming noise

its coming somewhere from the drivetrain

what is it likely to be? i've not long fitted the engine with new prop centre bearing, prop rubber joint, clutch etc
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andyp
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Sun Feb 13, 2011 12:18 pm

wheel bearing as a 1st thought or diff
TouringMatt
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Sun Feb 13, 2011 12:19 pm

Is it consistant with road speed?

Is it still there if you dip the clutch in?

Did you pre-load the prop brearing when you fitted it?

All problems i have had with droning or humming have been wheel bearing related, n/s/f one made a pulsing noise, o/s/r made a more consistant drone, both had the same outcome - fecked :?
Grrrmachine
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Sun Feb 13, 2011 2:14 pm

I went through all these checks, changed the diff, and found out it was the rear brake shoes!

Quck test is to remove the handbrake gaitor, mark the position of the two tensioning nuts, then slacken them off and go for a drive.

Even if the rumble is gone, return the nuts to their original position and deal with the shonky shoes accordingly at the hub.
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Barton
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Sun Feb 13, 2011 9:32 pm

it almost seems to be with engine revs

its hard to distinguish where its coming from, as it goes away when not under load or the clutch is down, but then the engine is also slowing down

i think the clonk when taking it out of second gear is returning which i believe could be the new rubber joint from the prop-box

the centre bearing was pre-loaded i.e. lined up the the car, then pushed forward somewhere between 5-10mm (and fuck doing that job again taking the old bearing off/new one on was a proper cunt)
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