19 replies to this topic

[nev_payne]

Sir D has recently developed a very loud, cringe-producing noise coming from either of the wheel/driveshaft areas or the clutch/flywheel housing.

- On idle and neutral the car is fine, starts fine, revs make no difference to that.
- Low speeds (under 20 mph ) produce a grinding noise form the passenger side.
- Medium speeds (20 - 40mph) produce a high pitched grinding / knocking noise.
- High speeds (40mph +) the noise cannot be heard over engine noise.

Something interesting to note is the knocking is really loud when foot is off the accelerator, but when accelerating, knocking stops completely. This happens through all gears, save for reverse (I haven't heard it as yet).

Unfortunately due to extremes of weather we are having here I haven't managed to look under him for obvious signs of knocking, nor can I get him up on axle stands and run him to find source of knocking, as my brother has his Mayfair up on all available stands.

Any help/ thoughts would be great guys

[miniboo]

wheel bearing??

[nev_payne]

wheel bearings are..pff... 3 months old!

[miniboo]

could be engine mounts if it is knocking when coming off the gas.

[nev_payne]

odd..would it do that as if connected to wheel? like i said its per revolution of the wheels..

[pikey7]

does it make a change when cornering? My guess is either bearing (but thats boring and safe ) or CV joint.

But, an easy thing to check first... is the big nut on the hub tightened properly?

[Guess-Works.com]

Either wheel bearing, CV, or possibly ( if over looked when wheel bearings last changed ) wear on the stub shaft of the CV, thus allowing the wheel bearing to 'wobble'.

[fikus01]

wheel bearings can fail even after a couple of months!!!

[minidaves]

my guess is loose wheel nuts

dave

[koss]

What i usually do in these cases is:- Jack the offending wheel off the ground with a sturdy jack, make sure your hand brake is on firmly or even chock the back wheels. Then start the car, put it in first gear and let the clutch out. You now have a spinning wheel.
Next apply a few revs and turn the wheels from lock to lock listening for the noise. If you dont get your noise try 2nd gear. You can also apply a bit of brake to simulate a load force. When you get your noise or knock, get your mate to have a look at the wheel , drive shafts, etc whilst in motion and knoking.
This might lead you to your problem.

Not recomended on a lsd diff.

ps be carefull you dont want your mates head jammed under the wheel

Edited by koss, 02 January 2007 - 09:20 AM.

[nev_payne]

my guess is loose wheel nuts

dave

First thing I thought - infact the sound sounds exactly like loose wheel nuts, but sadly they arent - wish it was that simple!! :'(

Would a standard MPi have lsd diff?

Edited by nev_payne, 02 January 2007 - 10:26 AM.

[miniboo]

no it wouldn't

[nev_payne]

thats alright then - will try that method tonite when home time comes

[fikus01]

knackered CV joint??

[blacktulip]

i think thats what mine is doing, the only way i can descibe it is like the noise when wringing a cloth mixed with grinding?