Ian Dunford

Half shaft taper cracked?
By the way that's not a Ruby.Might be a Diamond perhaps.

Location: Shropshire

Hi Ian

I have checked them and they do seem ok, do you think its worth changing them.

Location: south derbyshire

Sounds like the Torque Tube anchor to me too.

Location: A lot further south than Sandy

Could it be a brake binding on and releasing once its under pressure from the drive? The car seems to jerk forward as well as clunking when pulling off. I can see this thread degenerating before my very eyes. I hope you find a solution before things become too extreme...

Alastair

Location: Port Isaac, Cornwall

Hi Dave, the mandatory questions:

1) Did it "clunk" before you fiddled with anything??

2) If the answer to 1) is "NO", what exactly have you done between no clunk and clunk appearing??

Ian Mc.

Location: Shropshire

Does it make this rather sexy noise when pulling away in reverse?

Location: Moonraker country

brakes checked, everything seems fine. The jerking just my driving. thanks for your time
dave

Location: south derbyshire

hi Ian

the cluncking was already there when i bought the car. all obvious things checked. do you think it could be gear box area
Dave

Location: south derbyshire

hi vince
no noise in reverse
dave

Location: south derbyshire

Put it in to a low gear, eg 1st or reverse. Get underneath and rock car back and forth to see if you can reproduce the noise, and so you can see what is going on around the torque tube anchor point

Location: Farnham

You say there is no noise in reverse. Is the noise there when pulling away in 2nd? If not I would suspect the fault is in the gearbox and associated with 1st gear only.
Vince

Location: Moonraker country

A similar "clunk" on a car of mine eventually turned out to be the torque tube anchor plate on the cross member being slightly loose on its rivets. Rivets removed and replaced with HT setscrews and nyloc nuts - "clunk" gone.

Worth a check.

Ian Mc.

Location: Shropshire

Also worth a check are your half shaft nuts.

Location: Bristol

I am not sure that this audio puzzle is setting a desirable precedent!

It could form the basis of a competition with a prize!

Where will it end? Crankshaft rumble, timing rattle, little end knock, loose flywheels, spokes, wheels, flat retarded exhausts, moaning axles, knocking gears, rattling clutches, shuddering axles ... Perhaps we can have a downloadable audio library?
At last I have a justification for an upgraded sound system!

Some of these diagnostic inquiries have had an annoying tendency to fade away without the cause result being clearly made known. I hope we are not going to be disappointed this time!

Bob Culver

Location: Auckland

Hi Dave ,
Not being facetious , but could it be a loose spanner or socket , hidden under the seat or in the glove pocket , which rolls about as you first set off ??

Merv

Thanks David
i will try that
Dave

Location: south derbyshire

Thanks Ian i will check
Dave

Location: south derbyshire

hi Robin
it is a 1935 4 seater tourer AAL model. i put Ruby because i thought more people would be familiar with that model as all running gear is the same. its not the brakes though. thanks for your interest
Dave

Location: south derbyshire

hi Vince
the car cluncks in all forward gears but not reverse
Regards Dave

Location: south derbyshire

hi Ian
half shaft nut checked and ok thanks
Dave

Location: south derbyshire

HI Merv ONLY WISH THAT WAS THE CASE.
REGARDS DAVE

Location: south derbyshire

Engine mounts all nice and tight?

S

Location: On a hill in Wiltshire

OK I give up. Another nights sleep lost
Vince

Location: Moonraker country

No-one has mentioned loose rivets attaching clutch driven plate to splined hub.That would be a long shot,since everything else has been discussed. You would expect much judder when taking off in either forward or reverse.
Dave.

Location: Sheffield, the home of Henderson's Relish.

Sounds like torque tube. Presumably it also clunks on gear changes.
The tube lifts going forward. In reverse it drops, but it already is down so no noise. Am puzzled that car seems to visibly jerk forward, but that may just be A7 clutch!
Can see and feel torque tube thru the trapdoor. Can get underneath and push up and pull down on torque tube. Has the serrated ring come to end of adjustment as is common giving the impression of being tight?
Loose or worn clutch centres cause snatch and rattle at low speeds esp in top when not pulling.

Bob Culver

Location: Auckland

Location: Devon

It could also be a worn rear spring pin or loose rear spring.

Location: Ely

Initially I thought it was a loose hub as Ian has suggested. Have you checked that the halfshaft nuts are properly tight?

Location: Ely

Having listened to it about 20 times now, that is a good solid clunk occuring at the instant fwd motion begins. My money is still on something in or closely connected to the drive train.
I'd start with the bellhousing nuts and work my way backwards down the drive train ensuring that all fastenings and mountings are done up as they should be.

Passing thought, if nothing else is apparent, maybe pinion shaft end float or loose pinionshaft front flange securing nut - nicely hidden away, out of sight, out of mind??

Ian Mc

Location: Shropshire

AAL Tourer.
Torque tube anchor should be a non-adjustable silent bloc bush.

I think posting a video of this is genius, look at all the helpful suggestions it has provided, great idea!

I suffered a clunk such as yours for some time on the Ulster, I checked everything suggested above several times, including removing the pinion!

I only discovered what the cause of it actually was very recently when I decided to take the whole axle off and swap it. The Half shaft nuts were very light indeed, I had checked them many times but never removed them. As I started to undo the off-side one I noticed the half shaft turned with the nut a small amount before it wound off the thread. It turned out that the nut had bottomed on the end of the thread and the taper was not tight in the hub allowing it to rotate slightly and cause a clunk. A new hub fixed the problem and I did not need to swap the axle.

Hi Simon

i have checked , seem ok , but will repace
thanks Davedo

Location: south derbyshire

hi Dave
i have had the clutch out , everything seems ok,
thanks
dave

Location: south derbyshire

Thanks for your input. everyone has been very helpful. i will keep searching and give an end conclusion.
Dave

Location: south derbyshire

hi Bob
i have been away from the car for a couple of days. Back on the case this weekend. thanks for the advice from yourself and the many austin followers. i will keep everyone updated next week .
all the best
Dave

Location: south derbyshire

Try it on stands while someone listens/watches under the car.

Location: Queensland Australia

I have been waiting in anticipation for the answer to this problem. Don\'t know why, except that I hate loose ends.

Location: Shropshire

As do I, Robin. My pet hate is threads on the forum which just fade away with no news of the conclusion.

Ian Mc.

Location: Shropshire

Location: United Kingdom

"Clunk sound pulling off is definitely located in the rear axle and we are guessing that it is due to a broken half shaft"

Not sure but from my experience a broken half shaft stops pulling off????

Tony.

Location: Malvern, Melbourne, Australia

Thanks for the update, Matt. Although, if the halfshaft is truely broken, I would have expected the car to be incapable of any motion?


EDIT: "SNAP" Tony

Ian Mc.

Location: Shropshire

Just a thought, but does it make any strange noises if the handbrake is kept firmly on while the clutch is engaged? Maybe try it alternately forward and back but not allowing it to move.
This help might to isolate the region the noise comes from somewhat.

Location: Melrose, Scottish Borders

That's certainly a loud "clack", Dave! I think if you had a broken half shaft you wouldn't be going anywhere!! It sounds to me like a loose rear hub taper. If it was like it when you got the car, the chances are that someone has incorrectly assembled the rear hub and although the nut is done up tight, the hub isn't seating on the taper. If it's been driven in this state for a while, the key will have messed up the hub and the half shaft.

The only thing that keeps bugging me though is that the noise goes away in reverse Perhaps it is a brake holding on after all.

Location: Derby

I do hope we are told exactly what that noise is. It is one of those noises that seems to have got us all guessing!

And since May too!

Location: Derby

One must assume that the spare wheel is not 'loosely fixed'?

Location: Tropical Essex

My 1933 RP clacks going forward but not reversing. I have eventually found it to be due to a worn slot in the rear of the torque tube anchor. The mount twists and raps against the neck of the ball attachment on the chassis crossmember. There is far more wear on one side of the slot than the other so far less movement when reversing. Eliminating up and down movement does not prevent this twisting and there is no more adjustment on the very large castle nut to tighten things up.
This is my first post on the site and I hope is of some help.
Richard Masterman.

Location: Just North of Hadrians Wall

Location: Derby

Resetting the torque tube anchor " as per the manual " does not stop the mounting twisting. May be worth another look. Took me some time to spot this.

Richard M.

Location: Just North of Hadrians Wall

Always worth a second look

Location: Derby

Just found this old thread on YouTube and thought, What was the cause ? Having checked the tread again there was no explanation.It's a bit of a shame that contributors give a lot of thought and time to help only to be left in the dark as to the cause. Was it ever fixed or did Dave sell the problem on?

Location: Piddle valley, Dorchester.

I appreciate that this thread stopped a long time ago but I just want to say what a great forum this is. On a number of occasions I have done a simple key-word search on Austin 7 mechanical issues and this website pops up. On this occasion I did a search after spending a fairly tough week replacing a back axle on a A7 special I recently purchased at auction. The original back axle had broken teeth on the crown wheel. It had quite a few mods (7 inch hydraulic brakes on modified back-plates etc). Took a solid week to replicate the modifications and to replace. Needless to say I was full of trepidation about just how successful the replacement would be as I was not 100% sure about how well set up the new early axel would be. Heart sink when I got a clunking sound pulling off in FWD gears...hence the link here. Cut to the chase....one of the suggestions made early on was to check the torque tube socket/ball joint. Sure enough, when I pushed upwards it travelled about 3/4 inch! I thought I have seated it correctly but clearly not. Adjustment made, clunking gone! The relief was palpable. Thanks to this forum. David

Location: Derbyshire