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Old 06-20-2022, 08:11 PM   #1
hessam69
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Default Clutch shudder

On my 1990 240 with M47, upon take off there is a big shuddering vibrating feeling during engagement of the clutch as the wheels start moving. This happens to a lesser degree the more it happens (ie in traffic when the clutch warms up it smooths itself out)

What component in the clutch is worn? There is no slipping of the clutch and the point at which it begins to engage is very low in the pedal.

Thank you in advance
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Old 06-20-2022, 08:56 PM   #2
dl242gt
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The surface of the flywheel may not be smooth and flat anymore if there are a lot of miles on the clutch. Also the same goes for the pressure plate surface. So, with some wear from heat and use you can get some shudder in the driveline as you take off.

The springs in the disc are supposed to smooth out the takeoff. But they could be weak with age and I've seen clutch failures where they fell ouf of the disc.
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Old 06-25-2022, 05:46 AM   #3
Janspeed
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I'm not very familiar with the 240 but maybe the engine mounts are bad/broken/worn? If there is also a guibo (aka flex joint) between gearbox and drive shaft maybe also check that. (hard to see, use a pry bar to actually see if the rubber of the guibo is cracked.
Maybe the centre support bearing of the drive shaft is clapped out?

What i'm basically saying is: don't directly assume that the clutch is the problem. Check the entire drive line.
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Old 06-25-2022, 02:05 PM   #4
2manyturbos
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According to an engineer at McCleod the most common cause of clutch shudder with OEM type clutch discs is a marcel spring that has gone flat from heat resulting it something more like a race clutch disc. The marcel spring allows smooth engagement of the clutch because the disc actually compresses/drags on the flywheel/pressure plate before the clutch totally locks up.

https://motoiq.com/clutch-technology...-construction/
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Old 06-25-2022, 06:29 PM   #5
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^This, diaphragm spring all warped/too old & heat cycled/fatigued & shot, cracked flywheel surface &/or shot engine mounts/drivetrain parts loose...


Good luck. The clutch is chattering in my Honda Insect sometimes/intermittently, but it does have tons of miles/years on it (I'm kinda hard on clutches), city traffic, marginal motor mounts & I resurfaced the giant (for the engine size/vehicle weight & crawler 1st gear) flywheel (to cope with the brutal electric motor torque off idle in swept area)..I regret resurfacing the flywheel when fixing the trans & reusing the clutch, but whatever...I got another decade out of it? & it needs a 2nd gear syncro or close ratio Honda Fit trans swap, anyway...
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Old 06-25-2022, 07:18 PM   #6
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Could also be oil soaked.
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Old 06-25-2022, 07:22 PM   #7
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Quote:
Originally Posted by 283SD View Post
Could also be oil soaked.
Truth...oil or water or some sort of contamination is possible / common enough as a cause of chatter on a dry clutch...

Last edited by Kjets On a Plane; 06-25-2022 at 09:08 PM..
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Old 06-25-2022, 08:34 PM   #8
hessam69
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Thanks for the replies, the car is due for new engine and gearbox mounts anyway
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