drive line noise

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GEODAVKY
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drive line noise

Post by GEODAVKY » Wed Sep 25, 2013 9:25 pm

Looking for what could be causing a drive line noise at highway speeds. It doesn't be noticeable until you reach 60 mph or so. There might be some vibration as well.
Any ideas?
1967 330 GT 2+2 8767
George Davidson

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John Vardanian
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Re: drive line noise

Post by John Vardanian » Thu Sep 26, 2013 12:17 am

You'll need to first identify the frequency of the noise, meaning, is it in tune with wheel speed or the engine speed.

john
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tyang
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Re: drive line noise

Post by tyang » Thu Sep 26, 2013 6:30 am

Hi George,

Another thing you need to feel is where is the vibrating coming from. Do you feel it in the shifter, steering wheel, or even the driver's seat.

Tom
'63 330 America #5053

GEODAVKY
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Re: drive line noise

Post by GEODAVKY » Thu Sep 26, 2013 11:27 am

The noise is in tune with wheel speed. Put the clutch in and the noise is still there.
You feel it in the seat.
1967 330 GT 2+2 8767
George Davidson

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tyang
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Re: drive line noise

Post by tyang » Thu Sep 26, 2013 12:34 pm

Hi George,

Is the noise knocking or rumbling? Is it a dull sound, or a sharp metallic sound. All these clues leads you to the source. How tight are the wheels? I always check the easiest things first. Wheels could be out of balance. Swap front to back and see if it changes. Once you eliminate the wheels as the source, the driveshaft could be next to check. You could have a worn bushing that shows up when something vibrates.

Tom
'63 330 America #5053

GEODAVKY
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Re: drive line noise

Post by GEODAVKY » Thu Sep 26, 2013 1:11 pm

Wheels were tightened, but that didn't help.
I'll check the balance of each.
Bruce (working on the car) thinks it might be the driveshaft. He's at VIR so I cannot do any more until Monday.
What bushing are you speaking of?
I forgot to mention that my car has a high speed whine--something like straight cut gears. Don't know if that is related or not.
1967 330 GT 2+2 8767
George Davidson

DWR46
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Re: drive line noise

Post by DWR46 » Thu Sep 26, 2013 3:57 pm

Propshaft or rear axle. There is a "centering ball" at the rear of the propshaft to align the rubber donut. These can wear and cause the vibration. You will need machine work to resize it or maybe you can space the propshaft forward to cause the ball to run on unworn metal. Just some thoughts.

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tyang
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Re: drive line noise

Post by tyang » Thu Sep 26, 2013 4:12 pm

GEODAVKY wrote:Wheels were tightened, but that didn't help.
I'll check the balance of each.
Bruce (working on the car) thinks it might be the driveshaft. He's at VIR so I cannot do any more until Monday.
What bushing are you speaking of?
I forgot to mention that my car has a high speed whine--something like straight cut gears. Don't know if that is related or not.
There are a bunch of bushings like transmission bushings, motor mounts. They can wear and allow parts to touch and vibrate. The whine could just be a noisy rear diff. Does the whine change on acceleration and deceleration? may not be related.

Tom
'63 330 America #5053

GEODAVKY
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Re: drive line noise

Post by GEODAVKY » Thu Sep 26, 2013 4:23 pm

Thanks Tom.
I'll have to drive it again to tell you more about the whine.
I'll let you know what we find.
George
1967 330 GT 2+2 8767
George Davidson

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Art S.
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Re: drive line noise

Post by Art S. » Sun Oct 06, 2013 10:41 pm

George,

I had the same problem. As I recall, Francois found the cause by swapping components from a similar chassis that did not have the problem until the problem went away. In my case it was the driveshaft. It had been improperly reballanced by a prior mechanic.

Regards,

Art S.
1965 330 2+2 series 2 7919

GEODAVKY
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Re: drive line noise

Post by GEODAVKY » Tue Oct 15, 2013 3:15 pm

Local balancing place could not balance the driveshaft because of the way they mount them. The universal joint appears to be bad so we are going to replace it, but GP Car Parts did not have the 100mm size that my car takes. Trying Dennis McCann next. But if he doesn't have it any suggestions as to where else to look?
1967 330 GT 2+2 8767
George Davidson

cory
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Re: drive line noise

Post by cory » Tue Oct 15, 2013 3:49 pm

Hi George,
You could try Goeff Ohland at partsource in Camden Maine or email Scott Devonport. Scott will need a part # and description. He is in the UK but will get back to you promptly, scottdevonport@sytner.co.uk
Cory

tim
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Re: drive line noise

Post by tim » Tue Oct 15, 2013 4:18 pm

Greetings... You could look in the bottom drawer of the cabinet just inside the door to my garage. Brand shiny (well, as shiny as they can be) new. Let me know.

Tim
1964 330GT 5769 -the big yellow taxi 61&66 Morgan +4's Daimler SP250 and some other dull stuff plus a brand new Mini Cooper S Clubman JCWS

GEODAVKY
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Re: drive line noise

Post by GEODAVKY » Tue Oct 15, 2013 4:34 pm

tim wrote:Greetings... You could look in the bottom drawer of the cabinet just inside the door to my garage. Brand shiny (well, as shiny as they can be) new. Let me know.

Tim
I sent you a PM
1967 330 GT 2+2 8767
George Davidson

GEODAVKY
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Re: drive line noise

Post by GEODAVKY » Tue Oct 15, 2013 11:01 pm

tim wrote:Greetings... You could look in the bottom drawer of the cabinet just inside the door to my garage. Brand shiny (well, as shiny as they can be) new. Let me know.

Tim
For whatever reason I cannot get a PM to send. It's either stuck in the outbox or it says you don't exist.
In any case I am interested and would like to know more. Is it the 100mm one? I could certainly use it if it is.
Thanks,
George
1967 330 GT 2+2 8767
George Davidson

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