Screechy spinning noise taking up drive

Hi everyone, it’s been a while since I was last on here, I have been busy rebuilding my 90 onto a new galvanised chassis. Now I have a problem, when driving I occasionally get a noise when easing back on the accelerator gently whilst already in motion. It’s kind of a screechy metallic noise like you get when you have a stone in your disc dust shield however it appears to be from the bell housing. It stops as you take up load and accelerate. Now I have dismantled the clutch thinking it is related to the springs in the clutch plate. Long story short the clutch plate was a good old spare as we managed to wreck the new plate when refitting the engine during the rebuild....I know we should have ordered a new one. There are marks on some of the plate springs, spigot bush seems ok (that was new for the rebuild) but now I’m thinking “how could it actually be the springs??” Because it happens when already driving so clutch is engaged??? Does the clutch naturally slip when re-taking up drive as you coast then accelerate?? I know the springs are kind of shock absorbers. Just worried now it could be something else, I’m renewing all the clutch and spigot bush again when it arrives anyway...any thoughts or similar experiences anyone??? PS I removed the speedo cable as I thought it could have been that and drove with center seat cover off, the noise remained and did appear further forward ie bellhousing.
Oh it a 1994 300tdi defender 90

Mine did simlair and it was the gearbox input shaft bearing LT77 box.

Flossie said:

Mine did simlair and it was the gearbox input shaft bearing LT77 box.

Click to expand...

Do you mean the ones front and back on the transfer box where the props attach?

No, the one that supports the splined input shaft.that shaft has your clutch plate on it.

Flossie said:

Mine did simlair and it was the gearbox input shaft bearing LT77 box.

Click to expand...

Spigot bearing ?

Flossie said:

No, the one that supports the splined input shaft.that shaft has your clutch plate on it.

Click to expand...

Guess that’s a big job to replace? Never done one of those

Dippypud said:

Spigot bearing ?

Click to expand...

Nope.
That's new and not in the gearbox.

Naylz said:

Guess that’s a big job to replace? Never done one of those

Click to expand...

Don't know. My box was a bit rubbish anyway so I fitted a good s/h unit.

Flossie said:

Don't know. My box was a bit rubbish anyway so I fitted a good s/h unit.

Click to expand...

How did you know it was input shaft bearing? Was it obviously loose?? Or some other tell tale sign

Lots of up down play.
It was still working though but the baulk rings were worn too and it leaked.
I chopped off the input shaft for an enlignment tool and scrapped the rest.
Try it in difflock front then rear props removed as ujs make weird noises too.

I spent months tracking down a whirry/spinny/grindy type noise on my RRC. Problem was that it was intermittant and would sometimes disapear for days at a time.
Long story short, the mud shield on the input bearing on the rear diff was loose and sometimes was rubbing.

Is it the thrust bearing on the clutch?

Flossie said:

Nope.
That's new and not in the gearbox.

Click to expand...

Our 2005 90 TD5 made a very similar noise.

l had a new clutch, DMF and spigot bearing and the screeching/moaning noise was still there when pulling away in first gear, but not all the time, mainly when first used that day.

The spigot bush was replaced again (after being soaked in oil overnight) but it still did it.
The garage said they'd look at it again, but after a while the noise reduced and went away.