Prop shaft turning when in neutral

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Andyhereford
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Prop shaft turning when in neutral

Post by Andyhereford »

Some advice please.
The car is currently up on axle stands with all the wheels off the ground and wheels and drums off.
Today I started up the engine and noticed that although the gear box was in neutral the prop shaft and the rear hubs were slowly turning.
Reving the engine did not appear to have any real effect on the speed at which the shaft or hubs turned.
While to date I have only driven the car on the drive using first, second and reverse gears it seemed to change gear reasonably well.
Is this a case of the clutch needing adjustment, this turning of the shaft and hubs only being noticeable when there is not the normal inertia on the hubs caused by the drums and brakes OR is it something more serious.
Any suggestions would be appreciated.
les
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Re: Prop shaft turning when in neutral

Post by les »

You should be able to stop rotation by holding the prop, try it.

philthehill
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Re: Prop shaft turning when in neutral

Post by philthehill »

Nothing to do with the clutch. Transmission drag is the cause of the wheels rotating especially when there is no resistance further down the transmission i.e. rear brakes not applied.
Having the wheel rotate is quite normal when the rear of the car is off the ground and the brakes not applied. So nothing to worry about. 8)

Andyhereford
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Re: Prop shaft turning when in neutral

Post by Andyhereford »

As Les suggested I have just tried to stop prop shaft with my hand. It stopped very easily with no real resistance to stopping. What now if anything?
Many thanks as always for all the help from this forum.
myoldjalopy
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Re: Prop shaft turning when in neutral

Post by myoldjalopy »

Do nothing - its fine. 8)
Sleeper
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Re: Prop shaft turning when in neutral

Post by Sleeper »

It's down to the oil in the gearbox transmitting a slight motion to the output shaft....no problem.

John
Andyhereford
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Re: Prop shaft turning when in neutral

Post by Andyhereford »

Thanks everyone.
simmitc
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Re: Prop shaft turning when in neutral

Post by simmitc »

Do you know the history of the gearbox oil? You could try changing it for clean 20/50, but as others have said,nothing to worry about per sae.
Biggles1957
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Re: Prop shaft turning when in neutral

Post by Biggles1957 »

Love the pun Simmitc! Brilliant! :D :D :D
Andyhereford
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Re: Prop shaft turning when in neutral

Post by Andyhereford »

Simmic
Just changed all the oils but thanks for the suggestion. Seems that I was worrying needlessly.
Thanks
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