Rattle from inside bell housing - ideas required

[Henry Harris]

My 450se has seemingly started to make a rattling noise from inside the bell housing. Symptoms include:

• the rattle is there all the time now
• very pronounced from the bell housing when compared to the engine and to the gearbox
• it sounds like metal on metal
• nothing appears to be vibrating
• the rattle stops when the clutch is depressed
• having inspected the clutch and inside the bell housing, there are no marks nor apparent wear.

Simply put - does anyone have ideas as to what maybe the root cause?

[Tasmin200]

Sounds like a release bearing problem as it's stopping when you depress the clutch.

[Yatesy350i]

Mine does the same but it has a new release bearing. Pretty sure it's the GB input shaft bearing on mine as I could feel play when I changed the clutch.

[Jack Valiant]

Or the clutch pivot / lever. Had it on the Gredge pre engine change. Replaced release bearing as mentioned for a metal one VsV the cheap plastic ones and did the lever strengthening mod and all was well.

Best to get it up in the air with someone in the car working the pedal and have a good root round / listen.

C

[mrzigazaga]

Hi Henry...I had a rattle that went away when i depressed the clutch but its now gone away completely.

[adam quantrill]

Zig - is that because you threw all your toys out of the pram?? ;^)

Is the rattle disappearing with very light clutch pressing, or all the way?

I had a problem where the clutch plate inner flat springs had disintegrated, and were trapped in place, but then eventually the clutch started slipping too.

Edited by adam quantrill on Tuesday 5th April 16:45

[Terence]

I had a similar problem on a non RV8 engine. Had a faint rattle from bell housing that disappeared when I depressed the clutch pedal. I ignored it for around 18 months until I was forced to investigate by a locked up clutch. In this instance it was a broken anti-rattle spring in the drive plate that eventually managed to escape its retainer and wedge itself between the diaphragm spring and the pressure plate making it impossible to depress the clutch pedal. This is the only time I have come across this particular scenario, most likely cause is as others have suggested release bearing or worn input shaft bearing.

[Henry Harris]

Thank you everyone for your ideas so far. We will triple check and let you know.

[ElvisWedgely]

Sounds like an engine out job. Thrust bearings or spigot bearings as suggested. Good time to renew clutch and service gearbox. Will cost a bit but worth it in the long run.

Tony. TCB.

[adam quantrill]

I did my clutch (twice0 with engine forward 6 inches. It's tight but doable.

[Yatesy350i]

adam quantrill said:

I did my clutch (twice0 with engine forward 6 inches. It's tight but doable.

And me not too bad a job at all really. If it's the release bearing or arm or clutch itself you would be OK. Input shaft bearing is a complete engine and GB out job though. Hence the reason mine is still making a racket.

[adam quantrill]

Make sure there's a spigot bearing in the propshaft too - if that's gone then the input shaft to the gearbox can vibrate too much and break up the bearing or input shaft support metalwork.

[RCK974X]

Don't think it's been suggested above, can also be a broken/cracked 'finger' on the clutch plate spring - they can get wedged in, so don't fall out.

Most likely will be release bearing or actuating fork/lever is it stops when pushing pedal...

Bugger - gearbox off job....

[wild rover]

Gearbox can be split in the middle and the tail turned making sure the casing doesn't open. This gives sufficient clearance to change the fork and clutch.

[adam quantrill]

Req That's interesting do you mean rotate the rear 9" section? Presumably you drain it first.

That should get the lump at the bottom away from the crossmember which stops is going backwards. Propshaft will be off too.

Edited by adam quantrill on Wednesday 6th April 19:16

[Henry Harris]

Thank you again for all your ideas.

The short answer is the gearbox is out and will be examined over the next few days.

I'll post the outcome.

[Henry Harris]

Root cause identified as part of a tooth missing from fourth gear. Solutions being researched and photographs to follow, hopefully.

Suitable ideas welcome.

[adam quantrill]

Henry you busted 4th gear?? You hooligan! And you were going to put an LS1 in there - I dread to think how long the gearbox might have lasted... ;^)

[Henry Harris]

Thank you for the compliment Adam.

[ElvisWedgely]

A missing tooth would call for a recon gearbox wouldn't it? Then fill with good oil!

Tony. TCB.