Rattling noise - suspected gearbox

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rsawatson
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Rattling noise - suspected gearbox

Post by rsawatson »

I’m looking for some opinions on a rattling noise that appears to be coming from the gearbox area. Initially, I thought it was exhaust baffles but having changed the exhaust, no difference has been made. Whether the clutch is in or out makes no difference, and likewise whether the engine is on or off. However, the noise only comes when moving and peaks at about 20mph.

A friend suggest that it could be the anti-rattle - but no difference is made as to whether the gear lever is held or not.

I took this video - https://drive.google.com/file/d/1eLZIx7 ... p=drivesdk - I’d appreciate your thoughts. The phone was placed on the transmission tunnel just in front of the gear lever.

Thank you,

Ryan
Ryan Watson


Peted7202
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Re: Rattling noise - suspected gearbox

Post by Peted7202 »

Ryan

Just to be clear you say the noise is the same whether the engine is running or not. So it's there when you are coasting with the clutch disengaged.

If the noise is definitely from the gearbox area and under the conditions you describe there is only the propshaft universal joint and the gearbox both being driven through the rear wheels. Is anything fouling the prop?

I've listened to the video and it sounds more of a whine/rubbing sound. Maybe sound quality isn't to good.
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svenedin
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Re: Rattling noise - suspected gearbox

Post by svenedin »

I had a listen and I could hear the noise but it was quite quiet compared to the background noise. It sounds a bit like a stick in the spokes of a bicycle wheel. I'd second checking the propshaft and looking for any foreign bodies so to speak. While you're under the car check the backs of the wheels, brake pipes, brake backplate areas too. I would probably also lift each wheel off the ground and spin it to listen to the bearings and even check the tyres for stones. As you slow down in the video the noise slows down as well.

Stephen
1969 1098cc Convertible “Xavier” which I have owned since 1989.

Stephen
rsawatson
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Re: Rattling noise - suspected gearbox

Post by rsawatson »

Thanks both. I’m home from work and have just jacked the car up - I’ve discovered that the noise appears to be coming from the sliding joint area and is affected if I touch the collar (see video - https://drive.google.com/file/d/1BIOFCI ... p=drivesdk ). Any advice gratefully received!
Ryan Watson


les
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Re: Rattling noise - suspected gearbox

Post by les »

I think you will find the collar should be a fixed part of the yoke. Those indents on the sleeve indicate it originally gripped the yoke.

Peted7202
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Re: Rattling noise - suspected gearbox

Post by Peted7202 »

The collar should be fixed. Renew the indents with a small punch or centre pop.
les
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Re: Rattling noise - suspected gearbox

Post by les »

If you attempt to repair using a punch etc, rather than finding another yoke, you’d be well advised to remove before applying any impact.

rsawatson
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Re: Rattling noise - suspected gearbox

Post by rsawatson »

Thank you. So this sleeve should ‘pop’ in to the yoke and is simply an interference fit?
Ryan Watson


les
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Re: Rattling noise - suspected gearbox

Post by les »

Well, interference fit with the addition consolidation of the indents. As yours has become detached, you may find the interference fit is no longer effective.

oliver90owner
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Re: Rattling noise - suspected gearbox

Post by oliver90owner »

And for safety’s sake keep your hands/ body/clothing well away from revolving parts!
rsawatson
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Re: Rattling noise - suspected gearbox

Post by rsawatson »

A friend suggested degreasing and using Loctite, so I did. This seems to have cured the problem (for now at least).

Thanks all for your help and suggestions.
Ryan Watson


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