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Clutch & Gearbox
The gearbox appears to be OK but the clutch is seized solid
Mar 04 click for larger imageAfter the gearbox cover was removed, the clutch bell housing looked like this:
Mar 04 click for larger imageView of the clutch release bearing oiler.  This is the early type with clutch material rivetted to the flywheel and pressure plate.  See parts drawing below.
Mar 04 click for larger imageThe gearbox was just drained and refilled with SAE40 engine oil.
Later - as the gearbox was sluggish with poor synchro when cold, I filled it with Castrol 10W/60 fully synthetic, the same as used in the engine.  Result - good sychro on all gears from cold.
Apr 04 Despite having stood in damp conditions for over 25 years,  the clutch freed off with very little persuasion.  However there is some clutch spin until a gear is engaged (noisy !)

click for larger imageA very short test run showed that the clutch and all four gears worked well, the  brakes  less so.
Jun 04 click for larger imageclick for larger imageThe clutch pressure spring inside the clutch housing;   I don't know what that is shining ? - white paint maybe ?

Hairy assistant wonders what all the fuss is about ?
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Aug 04 click for larger imageFibreglass gearbox cover from  Available Austins  was a fair fit but needed some fitting.  Long 2BA screws into original threaded holes in gearbox cover plate hold it at the front.

a new rubber gearbox cover is now fitted  (see new cover) 
Aug 04 after fitting the gearbox covergrommet gives a good finish to the gearbox cover

. . . . . and the fitted item, with a close-up of the superb grommet from the  Vintage Supplies  range.  Access to the gearbox filler and the clutch release bearing oiler unfortunately means taking this cover off.
Sep 04 The dragging clutch was a nuisance when trying to engage a gear when stationary.  The old trick of touching one of the synchro gears before engaging first didn't work.  The covers were removed and the clutch operation watched through the inspection hole.  The problem appears to have been the centre plate sticking on the splines (even after oiling), probably due to rust on the exposed part of the first motion shaft.
Sep 04 view of clutch through inspection holePicture shows through the inspection hole:  foreground: the clutch bearing release oiler (GP6); at the top is the outer rim of the clutch cover (GP19), just above centre is one of the six holes in the driven steel clutch plate centre (GP25).  This plate is quite thick and through the hole can be seen one of the flywheel mounting nuts.  The pressure plate (GP22) cannot be seen in this view.
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Sep 04 identification of clutch partsOiling the splines of the clutch plate centre (GP25) had no effect so a little more cunning was applied.  First the clutch pedal was fully depressed; the centre plate was prodded with a long screwdriver until it came "unstuck" from the flywheel.  When it came free it was very free suggesting that the problem was caused by binding on the splines when the plate was fully forward.  It was slid the very short distance back and forwards over its splines (the centre clutch plate itself is springy and gives a little to permit a small amount of overtravel).  I filed a slot in the end of a prybar* to fit over the webs of the centre plate so I could slide the plate back and forth with some vigour.  A noticeable improvement in the ease of movement was noted after about 10 minutes of vigorous pulling and pushing !
Sep 04 tip of clutch toolmodified pry-bar used to pull/push centre plate on splines* A prybar is a small crowbar - effectively a solid piece of metal with the tip bent at a useful angle for inserting down into the inspection hatch. 

With the engine running, I can now depress the clutch pedal and watch the centre plate (and with it the gearbox primary shaft) stop rotating.  Clutch spin eliminated 100% ☺    It is now so good that I sometimes have to partly release the pedal to rotate the gearbox to engage a gear !
Apr 05 click for larger imageand to finish it off, new clutch & brake pedal rubbers from  ATDC Spares 
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Apr 06 It occasionally jumps out of bottom gear; usually on a long hill where you really need bottom gear !  Checking up in Newnes vol 4 page 425 shows that "the gear most likely to cause trouble is the first speed gear" - due to the locking ball not holding the selector firmly in position.  Later models (1936-on) had a modified selector shaft but one dodge is to rotate the 1st gear selector shaft so the ball slides into an unworn part of the locking groove.  This can be done without any dismantling.
Apr 06 click for larger imageclick for larger imageSo as the clutch bearing needed oiling, whilst the gearbox cover was off, I took off the gearbox top cover.

The lock plate just lifted off  and the 1st gear selector shaft marked
Apr 06 click for larger imageclick for larger imagebefore slackening the locking nut and rotating it 90°

The gasket fell apart so a new one was tapped out - years since I have done this and very satisfying !
Dec 06 yes, bottom gear definitely stays in better - though the gearbox is overall much quieter and smoother after 2,000 miles on fully synthetic oil (Castrol RS 10W/60, the same as I use in the engine).
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