M50 engine noise

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Wed Jul 20, 2016 8:16 pm

Anyone have any idea on the vibration type noise in the video, it seems to start at 1400rpm, and is not an accessory e.g alternator, as the belt has been disconnected, and still the same?

Thanks
Motorhole
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Thu Jul 21, 2016 9:44 pm

It's always difficult to tell from videos and I don't want to be a doom-monger but that sounds a bit bottom endy to me. Might be worth getting a second opinion from someone who can see the car in the flesh.
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Thu Jul 21, 2016 10:10 pm

Yeah I was a bit worried about that, as the history of the car is unknown, although thought it would be more of a knock if bottom end, and a tap around the head?
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Thu Jul 21, 2016 10:10 pm

Yeah I was a bit worried about that, as the history of the car is unknown, although thought it would be more of a knock if bottom end, and a tap around the head?
Thanks
Motorhole
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Fri Jul 22, 2016 2:46 pm

Not necessarily - from the video, it sounds like a 'thrum' that increases with rpm which is what I'd consider 'bottom endy'.

Hopefully it's not!
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Sun Jul 24, 2016 11:20 am

Yeah thanks mate. It's strange as its like a vibration/ harmonic, but is hard to pin down. Around the sump it's not so loud, but on the intake side it seems louder. This may sound stupid but it kind of sounds like it's coming from the flywheel!
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pianist
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Sun Jul 24, 2016 11:49 am

Don't wait any longer check bottom end, I did and it's beyond repair now :cry:
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Sun Jul 24, 2016 6:53 pm

pianist wrote:Don't wait any longer check bottom end, I did and it's beyond repair now :cry:
was yours making the same noise?
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pianist
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Sun Jul 24, 2016 11:15 pm

Yeah I thought it was my tensioner knocking (not m50) so was driving it for a bit and one day it just started losing power on the way home until it stalled, when I got it home took sump off to see loose piston rod on the crank and in engine shop I been told the crank journal was too far gone :(
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Mon Jul 25, 2016 11:28 am

I've bought a stethoscope to try and pinpoint the noise, as the noise is still there even once a spark is removed(quick test for rod knock)? If it is I'll try and drop the oil pan, it's just quite a big job to do with the engine in the car.
Thanks
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