Excruciating wail from gearbox

[Boris64]

Good morning. The junior mechanic and I have been enjoying 18 months of trouble free motoring which has just come to a noisy end with a gritty, screeching racket from the bell housing area.

The noise stops on depressing the clutch pedal and when in neutral but increases with speed. It's common to all gears.

End of the clutch plate?

End of the thrust bearing?

End of the gearbox?

Any advice appreciated and happy Mother's Day in case you forgot

Pete

[bigwheels]

There is a little needle bearing at the end of the gearboxes first motion shaft that is always rotating both at idle and driving in gears. The gearboxes first motion shaft main bearing also working under both neutral and drive conditions the symptoms you describe could be wear in either bearing or both! If the gearbox oil levels are low you would hear a small amount of noise until the clutch is depressed but nothing drastic! Basically when you press the clutch down the first section or length of the gearbox stops rotating. Learn to live with it or remove the gearbox for repair if the oil levels are OK but adding oil to a very noisy gearbox is probably going to be a waste of time and oil in my experience!

[bmcecosse]

First check must be - is there any oil in it..? Otherwise as above - swap in another box while you investigate your own..

[Boris64]

Thanks both for the prompt advice.

Assuming the oil is ok (I'll check when the rain stops), you're both suggesting gearbox issues.

No chance it could be the easy and cheap clutch/thrust bearing?

Pete

[kennatt]

If it was the thrust it would be Worse when depressed since its not moving when the clutch is out,only when it touches the pressure plate on pressing the clutch,'if it was the bearings on the first motion shaft I would think it would be there in neutral as well since its still turning with the clutch out,if it was gone ONLY when the clutch was pressed,then yes first motion shaft,since the shaft is then not being driven,but out of gear with clutch out still drives the shaft.
Unfortunately looks like gearbox internals,but boxes are relatively cheap S/H and not too bad to swap,never been one for rebuilding boxes,just think it works out much more expensive,and unless you change all of the main internals always a risk you miss something and still have a problem.

[bigwheels]

Unfortunately the Gearbox is my prime suspect from the symptoms described. I personally haven't had any luck with finding good used gearboxes and ended up rebuilding / repairing one but do check for play on them before fitting only a tiny amount of deflection is acceptable on the tail shaft preferably none!

[bmcecosse]

The main clue is in your title.... 'wail from gearbox'...

[IslipMinor]

Pete,

When did you last check the gearbox oil level?

[Boris64]

Thanks all for the advice and apologies for the late response.

I've gone for the quick turn around that I hope a second hand gearbox will allow. Time will tell.

The visible bits look like new inside but difficult to judge the bearings. Both ends turn freely by hand.

Any thoughts on what I ought to do to it before fitting next w/e? Apart from removing the old one first

Thanks

Pete

[katy]

Check the pilot bearing in the end of the crankshaft.

[Boris64]

Katy

Thanks, do you mean the spigot bush?

Pete

[bmcecosse]

He does indeed....

[Boris64]

Ouch, another £3

[bmcecosse]

I suggest that's the very least of the worries... You only need to 'check' it - to make sure it is there/not shattered.

[Boris64]

Thanks

Second hand box came without this so can I assume I just reuse the current one if it's in one piece?

Pete

[kennatt]

its not on the box,its in the engine on the end of the crankshaft,its where the first motion shaft on the gearbox fits into the engine ,it will still be here just have a look through the clutch plates and see if its not broken up.Do you not have a workshop manual,google it .

[Boris64]

Thanks for the note.

I'll take a look when I have everything out.

I have my fingers crossed that it will be fine (and the issues are internal) and hopefully get everything done tomorrow.

Pete

[Boris64]

Today's plan was a quick change of gearbox in an attempt to cure the wailing.

No too difficult to get the engine and 'box out but the choke cable got a good stretching

I had a poke inside the ebay gearbox with a magnet and wonder if anyone recognises the bits in the photo that were hanging around?

Pete[frame][/frame]

[Boris64]

Whilst sulking about my ebay investment I took the clutch cover off.

Could this be the cause of the wailing or is there still mileage in the plate?

I could find nothing in the current 'box with a magnet and the mechanicals are certainly smoother so I've fitted a new oil pump and put the old box on the new clutch.

A risk I know but I thought I could get everything back together.

Just how do you realign the propshaft splines with the tail of the gearbox?

It's too dark to see so out with the whisky.

Any advice appreciated.

Pete[frame][/frame]

[panky]

I'm guessing you left the prop attached to the flange on the axle, probably would be easier to undo the four bolts so you can twist the prop and line up the splines.
The bits look like what's left of a bearing cage and a few shredded teeth