propshaft knocking

[RiF]

Is this OK????

When sitting at rest with engine on tick over and clutch up there is a lot of noise from the prop area, like a knocking/noisy clonking. This never use to happen. Prop is dead square, well greased, nipples OK, and no problem otherwise. Goes once clutch is depressed. Do I just live with it? Got a few long trips so thought I should ask

 

RiF Driving one of the first Duratec 7, and building CA07BON for Henrietta 😬 😬 😬.for pictures of 7 and carbon andCA07BON

[neilg]

CRB?

[paul richards]

This sounds normal to me. I understand it's the layshaft in the gearbox and my car has always done it. It's worse if you have a light flywheel and also if you are on a hill - can't remember whether it's worse facing uphill or downhill, but one is worse than the other.

I don't think I'd be worried. CRB is normally a screeching sound when clutch is activated.

 

Paul Richards

Area Representative - L.A.D.S. (Lancashire and District Sevens)

LADS Website

Growing old is compulsory - Growing up is optional

[DaveMorris]

RiF,

it can't be the prop when you're stationary as it isn't going round.

Layshaft is the most likely cause as Paul says.Have you changes gearboxes recently (or had yours overhauled, or changed the oil in it .. ... ....)

Dave.

[wild bill]

I have had the same mystical clonking problem recently and now my question is answered as i had a gearbox rebuild and fitted a lightweight flywheel and wondered why car had a new clonking sound. I thought it was the P/S too but layshaft makes complete sense to me, now much happier

 

 

[RiF]

Thanks for the replies. It makes sense. I will stop worrying about the prop taking my legs off I will get back to thinking about change the BGH gearbox for an SP semi hellical one.

 

RiF Driving one of the first Duratec 7, and building CA07BON for Henrietta 😬 😬 😬.for pictures of 7 and carbon andCA07BON