When I change gear on taking up the drive my car emits a loudish dull like clonk. This only happens each time I change gear or put my foot down to accelerate. At first I thought it was a loose exhaust but this turns out not to be. It sounds like a universal joint has called it a day maybe. But where? Any help appreciated.

First what type of Seven is it? secondly have you checked that your wheel nuts are tight?
Chris

Three things to look at, first yes the UJ,s but if one has reached its "sell by date" you tend to hear it rattling all the time, second is the torque tube mounting tight? and perhaps the most important of all, are the hubs tight on the shafts, if that big nut is not as tight as you can get it, the shaft will try to turn inside the hub and what you can hear is the key moving in the hub and axle shaft! but my bet is on the torque tube mounting.
Regards John.

I'd check the torque tube mounting first as well.

STEVE

on my seven i had a strange clunking every time i pulled off and it was caused by the hub not being tight on the half shaft. I ended up on the end of a tow rope again...!

i would check both hubs are tight as both of mine were very loose

I was recently involved in solving a problem showing these syptoms in a Mk 2 Ruby and we went down the the road described above to no avail. The fault was eventually found in the torque tube where the locking nut was loose (although still locked)and the spacer/collar had fretted sufficiently to allow axial float of the pinion. The bearings still had some grip on the pinionshaft and the clunk occurred as the shaft was forced one way on take up and the reverse on over-run. Sadly the CW& P needed replacing.
Hope this helps
Ron

Thank you all, today then its off with the wheels for a check around. Getting underneath is more of a problem, oh for a garage pit for Christmas

Re. the half-shaft nuts, when we say tight, we mean TIGHT, I have a dedicated ring spanner for the half shaft nut with one end cut off so I can slide a 3'6" scaffold tube over it and then use my body weight (or one foot with my body weight behind it - NOT standing on the tube, other foot's on the ground). That's what I call half shaft nut tight!

Sandy

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How, in particular, are you holding the hub from turning during this exercise Sandy? I know there are several methods.

Mike

Are you serious Sandy Today I'm off to collect my recored rad', get that put back in then tackle this clonking

Mike. You can use an old brake drum with a piece of 3ft steel welded on the outside. Then put on hub with drum screws and wheel nuts in place

Mine were tightened by someone who knows, with an air hammer. Tight enough to strip the thread straight off one of the old nuts and to need a washer on the other as it pulled the hub onto the taper so far that the split pin was floating rather than in the castellations. I too am wondering how I am going to retighten (if they need it)as surely anything that doesn't either prevent the shaft from rotating in the diff (ie a wheel in contact with the ground), or can tighten quickly before it rotates (ie an air hammer), will just rotate the shaft. I remember someone saying they had an old wheel with central access, but is there something more practical for those of us who have not accumulated a few years of A7 bits and pieces?

I use Normans approach, very effective. The old brake drum with a 3ft bar welded wprks a treat.

Regards

Chris

John Sutton of Camco Solutions published a data sheet containing torque settings fo all the bits of Austins that need to be tight (but not too tight). Don't know which source he got them from though....

Make sure the tapers are at least reasonable with no high points or ridges and make sure they are not worn to the point that the halfshaft taper pulls through the hub. David Cochrane sells new half shafts and rear hubs if you want to be sure. Make sure the key (if you are using one) is not 'bottoming' in its key way. Use a proper fitting socket and a 3' bar. Use new nuts as it's easy to pull the threads out of the now rather old and worn originals. Use a wheel/tyre with the centre removed or an old brake drum with the angle iron welded to it, chock all the wheels well and tighten as hard as you can.

Remember that if the hub is fitted properly, the key serves no purpose. The drive must be transmitted through the taper, not the key. If the drive is through the key, it will fail quite quickly.

HTH

STEVE

I wedged a peice of 3/8 steel bar through the studs and onto the ground to stop the hub turning. I then used an 18" bar with a scaffold bar slipped over it and lent on it very hard!

This is not a good method because you could easily damage the studs ( I have special 3/8 high tensile studs). The other way is to use an open centre wheel with the centre knocked out, or a modified drum as stated.

They need to be very tight!!!! The tapers should be in good condition, and in theory you could drive without keys if the tapers were good and you tightened up well ( in my opinion the key is not designed to transmit the torque). Brojken halsfshafts will be the result of not tightening enough or using poor tapers ( hub and halfshaft).

Steve

Sorry for repeating what you said Steve!! We must have been posting at the same time!

Steve

Mike - Yes I'm using a brake drum with a welded 3' length of steel on it, about 3" x 0.5" in section, this bits into the ground.

This method was shown to me originally back in mid 60's by the 750MC section in Southampton (pre Solent Club!), and I was reminded of the method about 5 years ago in Cornwall when my halfshaft went by throwing the car into reverse as I was decending a 1:4 hill into the village, single track with a someone coming up who forgot to slip into the passing bay and apparently could not use reverse or gravity as I found out later. Any way the road was blocked just as the hoards started to arrive for Chapel, so it did not take long for the whole village to know about the event and old cars and ........

So yes, I use a leverage of 3' on the half shaft nuts with the hub held firm.

I check/tighten the nuts every year about a month before the MoT - part of my full annual check-up.

Sandy

Steve, I did try the bar on the studs method, then replaced the studs........

But it seems we are applying similar pressure on the spanner 3'+.

Sandy

Trouble with jamming something between the studs and hub centre is that you are liable to distort the studs off centre - even with the wheel nuts on - and without them you will knacker the threads as well

There have been lots of useful and valid suggestions about getting the halfshaft nut really tight and I suppose everyone has assumed that the hub will have been nicely lapped on to the halfshaft. One tip that hasn't been mentioned relates to removing the ridge caused during the lapping process. Having lapped the hub, if you examine the outboard part of the taper inside the hub you will see a ridge where the halfshaft came short of reaching the end of the hub. When you subsequently pull the hub up tight, the halfshaft will bottom on to this ridge which will severely limit the "grip" of the taper. This ridge must be filed off. If left on and you pull up with all the methods described above no doubt the ridge/hub interface will distort into some sort of "acommodation" but this isn't good engineering.
I'm all for pulling hubs up very tight and checking again at intervals but ensuring there is no ridge is an important part of the job.
Ron

Ron,

Many thanks for 'the ridge' details (removal of).

I have done it before, but memory is getting slack - no comments please!

Thanks again Ron for the tip.

Algie