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post #447 of (permalink) Old 05-26-2018, 07:43 PM Thread Starter
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Shakey's Avatar
Join Date: Apr 2013
Location: Columbia, Missouri, USA
Posts: 544
I've been doing a bit of 'read-ahead' for when I shortly return home. The shop manual says I should have marked the orientation of the clutch cover in relation to the flywheel; I am reasonably certain I did not.

If memory serves, the cover is symmetrical, and can fit any of three ways. Is this genuinely a concern? If so, what is the best way to proceed?

What follows in the next several posts is a discussion of the virtues of having indexed the flywheel, clutch disc, and pressure plate before disassembly, and balancing the whole assembly. Let me skip to the end, and say that the car is running great, with no vibration or problems of any kind. In order to frame the discussion, we should characterize the flywheel/pressure plate/clutch disc assembly as UNBALANCED, BALANCED, or OUT-OF-BALANCE.

An UNBALANCED assembly is as it came from the factory. The parts are bolted together without regard to specific orientation. The minor variance in mass production does not generate any unusual vibrations. My assembly was UNBALANCED; it did not matter that I didn't mark the components during disassembly. I put it all back together, and it works fine.

BALANCED is where the components of the assembly have been evaluated, and bias applied (in the form of weighting or lightening) to obtain the minimum rotational vibration. I would imagine this is for racing, or high-RPM performance applications. The orientation of the components is now important, as they now contribute to the bias that achieves the smoothest operation. Indexing the components before disassembly is now important.

OUT-OF-BALANCE is when a balanced assembly has been reassembled in a misoriented manner. The components' bias that previously contributed to a balanced assembly, are now at odds with each other, and my actually induce vibrations.

I hope this on!

1988 Spider Veloce (with lots of 3D printed parts)

Last edited by Shakey; 09-02-2018 at 11:15 PM.
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