Re: Spider drivetrain shutters when slowing to stop

[Caxambu@domain.elided]

Judging by the description, this sounds like it could be bad driveshaft 
u-joints. The common failure mode is for them to first tighten up (lack of 
grease?), then loosen up as the needle bearings disentegrate into dust. The 
best way to inspect them is to remove the rear section of the driveshaft 
(after marking all connecting surfaces for correct realingment) and rotate 
the joints. The movement should be entirely free and smooth, with no binding 
or slop. To replace the u-joints, obtain genuine replacements, and, unless 
you are an expert in this field, try to find a shop you can trust-- the 
driveshaft is rather fragile in that it does not hold up well to pounding.

Also check the rubber donut at the rear of the transmission. Replace it if it 
looks cracked, separated, or deteriorated. But the sound you describe seems 
like u-joints. The Spiders are hard on them.

- --Caxambu
1969 1750 Spider
Seattle WA

> ------------------------------
>  
>  Date: Tue, 23 Nov 1999 18:54:45 EST
>  From: "Wallace Martin" <sallgdon64@domain.elided>
>  Subject: Spider drivetrain shutters when slowing to stop
>  
>  Recently encountered the strangest problem on my 1984 Spider Veloce:
>  
>  When coming to a stop with the car in gear and clutch depressed, as the 
>  RPM's fall to about 1000, I get a rapid "thump-thump-thump" from the 
>  rear/underneath area, and the engine begins to stall.  The shuddering then 
>  stops and the engine RPM's return to idle.  The behavior the same when 
>  stopping with the car in neutral and the clutch disenaged.
>  
>  As further info, the clutch seems to momentarily slip with a squalk/squeal 
>  occasionally when accelerating and letting clutch out.
>  
>  I jacked the car, and was able to freely turn the driveshaft/differential. 
 
>  Filled and vented the clutch operating cylinder, and movement of clutch 
>  operating cylinder piston is in spec with the manual (about 1/2").
>  
>  Engaging the rear wheels while running the car on jackstands brought on 
the 
>  same "whumping". My current plan of attach is to replace the clutch.  Does 
>  anyone have any info on this job? I've got the factory manual for 
guidance, 
>  but I seem to recall some "engine-mount loosening" technique from 
>  Alfa-Digest.  Any other tips, or idea about the root of this mystery would 
>  be greatly appreciated.
>  
>  Thanks in advance,
>  Wallace Martin
>  

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