Any ideas anyone please?

[Austin Nippy]

Good evening everyone,
Given the good weather the Nippy has been my "daily driver" for the last few weeks and has, as usual, performed admirably in the task - until earlier this evening.
The Sheffield Parkway was suffering from very stop start traffic of which I was a part. Without warning, on changing up into second gear, there was a loud metallic - sounding rattling noise which then stopped as suddenly. However, unless the car is rolling, it is almost impossible to engage any gear and the rattle appears intermittently regardless of road speed / engine speed / gear engaged / clutch pedal up or down. It sounds very like a set of marbles or ball bearings or similar are flying around somewhere within the mechanics of the car but don't really know where from. 
I managed to nurse the car home but suspect something fairly terminal is happening - possibly in the clutch somewhere? 
Does anyone have any clues what this may be and, probably, who may be able to either advise on a fix or, in all probability, perform the necessary repairs please? 
Many thanks in advance,
Nick

[David Stepney]

Collapsed clutch release bearing, perhaps?

[Chris KC]

Nick,

When you say "almost impossible to engage any gear" what is happening? Loud graunching sounds? Or is it physically hard to move the lever? Or something else...

My first thoughts are it must be clutch or gearbox, and needs to be narrowed down.
Start with what can easily be checked - for example, with the engine switched off does pedal operation feel normal? Can you now select gears?

You can see a certain amount down the opening for the clutch release bearing oiling tube. Peep down there with a torch and see if anything is adrift. As David suggests, clutch release bearing, maybe a broken clutch lever, bits of disintegrating lining?

From there I'd remove the flywheel cover - it's only 2 screws but can be a bit of a fiddle to get it off past the flywheel. Again, take a deep look inside, using a mirror if necessary. Then the gearbox top - 6 x 1/4 BSW screws. In 4 speed synchro boxes it's not unknown for too much free play to result in detent balls and springs pinging out. You might need to drain down the oil to see properly.

With luck these probings may reveal the cause and you just might find something which can be fixed in situ. Failing that it sounds like the engine must come out to provide access for analysis and repair.

Sorry if all the above sounds obvious but nothing is leaping out at me - you've just got to systematically work through the possibilities and it's usually best to start with whatever is easiest.

[Colin Wilks]

In the first instance I would want to listen closely to each element of the drive train in the absence of engine noise, so would put the rear axle up on axle stands and then turn the engine over on the starting handle, after removing the plugs so you're not fighting compression, and try all the permutations of clutch and gears to see if you can decide on the source of the noise. Dropping one rear wheel to the ground, chocking it, and then turning the other would allow you to rotate everything from the propshaft side of the gearbox.
PS disconnect the inlet to the fuel pump before turning over.

[Chris KC]

Another possibility which crosses my mind is front bearing cover plate gone.

[Charles P]

Another possibility which crosses my mind is front bearing cover plate gone.

I think that you may have nailed it.


c

[Rick F]

Another possibility which crosses my mind is front bearing cover plate gone.

I had a previously repaired front bearing liip plate shear off. Very musical as it flayed around on the crankshaft, but did not affect driving/gear changing. Would not the same conditions apply to to the front cover plate in the unlikely event of all four bolts coming loose?

[Chris KC]

A replacement lip failing would not affect the clutch directly as it forms the backstop for the front bearings.

However if the front plate came loose the shaft would shift forward under clutch pedal pressure and might impair clutch function; A certain amount of clatter to be expected too.

A front cover plate might come loose if the screws / nuts were not tightened properly / locked, in which case more than one doing the same thing under the same conditions of operation is not unlikely.

I've seen a few variations on how lip repairs are done and some are more robust than others; they are not unknown to fail and if they utilise the same screws - often low tensile - as secure the front plate then there's a potential link.

Not saying that's it but - possible.

[Steve Jones]

Something similar happened to a Class 1 Ulster competitor at Shelsley a couple of weeks ago. Broken clutch finger that then fell into the works!

Steve

[Charles P]

A replacement lip failing would not affect the clutch directly as it forms the backstop for the front bearings.

When my replacement front lip went, the crank moved back, the clutch fingers hit the clutch pedal operating rod and everything went very clattery. Part of the noise was the steel lip being beaten to shreds by the rotating crank, leaving pea-shingle sized steel fragments in the sump. The clutch would operate, but not very well, but with a 3 speed box gear changing doesn't always need the clutch

Charles