EXPERTS (AND PSYCHICS) need apply....

[GeoffSmith]

If it is a regular knock directly related to road speed then it's more than likely drive train and not engine mounts etc.

Thinking out loud: Try lifting one side of the car then the other and see if you can reproduce the noise. If it's there no matter which side is lifted, then it's probably gearbox. If it's there on one side only it's diff, driveshaft, CVJ or wheel bearing (If you can, try comparing the frequency with a road test at a given engine speed and gear - the frequency should double as the raised wheel is going twice as fast because the other wheel is stationary).

As Candles says, you should be able to detect wheel bearings with the wheel raised - try rocking the wheel in the vertical and horizontal axes. If it's CVJ's try turning the wheels to full lock both ways and see if you can feel any 'lumpiness' in the joints as you turn the wheel.

Good luck,

Geoff

[timmo]

Seems to narrow it down to bad CV joint(s) or bearings at the wheel or transmission/differential.

This gets my vote, transmission related but NOT the box.Either inboard or outboard CV joint.

[brubaker]

So I've summarised all the thoughts of this ever useful forum into a report for my mechanics. We'll know tomorrow!! The sucessful diagnosis gets a internet six pack from me...

[Candles]

Well it is definitely a wheel bearing so I'll get my beer cooler and lazy boy out right now....

[brubaker]

C,

If it's only a bloody wheel bearing - I'll buy you a whole crate That really would be a result...

[brubaker]

C,

If it's only a bloody wheel bearing - I'll buy you a whole crate That really would be a result...

[Candles]

Is that two crates then?

[brubaker]

C,

If it's just the bearings you get two crates That avatar looks like a pacific blue s2?? which coincidentially is the one that I have...

Picked it up a little scruffy (good mechanically) slowly but surely it is being transformed back into a butterfly...not sure about that parallel

PJ

[Doug]

you're lucky, cause Candles is the man who knows the tranny more intimately than any of us!!

Get the credit card out and start heading to the liquor stop . . .

[brubaker]

Doug,

I feel highly honoured that you've joined my thread to find out what the hell is wrong with my S2...the founder...
'I stand in the midst of great warriors' - sorry blagged from Saxo's History of the Danes - nonetheless...I hope you are right, as is Candles.

PJ

[brubaker]

SO.....

It's not the wheel bearings We rocked the wheel off the ground to the sound of Van Halen...it seems fine.

Curiously the car was making the sound as I drove it to the garage - we put it on the ramp to do some diagnostic tests - when we put it back down and drove it the noise had stopped...having done nothing...after a drive in the wet we couldn't even get it to make the sound...Lotus...

Anyway we think it is either CV or driveshaft on the right hand side so I've ordered a new drive shaft from Chris Neils...£175 but it won't be in NI until next week...Only then will we really know...

Again the help is invaluable as ever...does that mean I keep my beer

[Candles]

No! Coz it still is a wheel bearing. Mine had no play in it but still made a rhythmic clunking noise. I replaced the driveshaft and centre bearing before doing the wheel bearing, which fixed it.

If you dismantle the hub, i.e. hub nut off and swing the thing off the driveshaft (puller needed! - all detailed in the manual), you can feel with your fingers the freeness of the bearing. This was where mine failed the test. In all other tests I hadn't detected the source of the clunk.

Do you know which side it is? If not, it is the crazy-car-park weave for you my friend! Keep a steady speed in a wide open space of smooth tarmac and weave left and right. If the clunking gets faster when you go left, it is the right hand side, and vice-versa. Have a passenger to cross-check as well.

Candles.

[Perth_Elan]

I have only quickly read the posts so I may have missed this comment

Have you checked the support bearing on the R/H drive shaft ?

As the CV's have been checked OK you say the wheel bearings are also OK the is the only bearing left other than inside the gearbox. Worth checking before you take the box out.

As for wheel bearing be very carefull that you have checked them fully, I had the R/H wheel bearing fail a MOT (when I lived in the cold country) and when I took it apart it was not the actual bearing but the nut had never been done up fully !!! (no way the locking tab can let the nut loosen) or maybe the outer race had not been pressed in fully from day one and so on assembly it was OK until the outer race moved fully home and then loose wheel. When I say loose I think I remember getting another 3 turns of the locking nut and and then all was OK

[mikeydude]

I don't have much experience on this, but from what I have seen of the elan Drive train it's not likely to be the gear box....not after only seventy odd thou. it's more likely a wheel bearing or cv joint me thinks

[Monty]

Thought my gearbox was whinding, i checked bearings, no play and had it have the ground in gear and still couldn`t tell were the noise was coming from. I even took the car to an X lotus mechanic, he put it on ramps and was still difficult to tell were the noise was coming from and he said it was the diff bearings. Anyways i swapped the gearbox with my spare one which had a quaife ATB fitted and the dam thing was still whinding and it did turn out to be the wheel bearings and the only way to tell was to remove the hub and turn by hand.

[brubaker]

I have ordered new wheel bearings from Chris Neils - they are the cheapest option and I think that is good advice

PJ