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HR clutch height adjustment

Old Jul 29, 2016 | 08:01 PM
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Default HR clutch height adjustment

Hello everyone,

I adjusted the clutch height to where I wanted it and came out the next morning to my clutch stuck engaged.... Which brought me to this thread

https://my350z.com/forum/engine-and-drivetrain/582562-clutch-pedal-issue-after-adjustment.html

If you read a few posts down you see RJM performance explain how the clutch assist spring puts continuous pressure on the master cylinder which can cause problems.

I raised my clutch a bit to drive to work today and after work it was lower again (not stuck engaged, but lower.)

Has anyone tried removing the clutch assist spring on HR ? I keep finding stuff about the older generations. Any other solutions besides $300 on an aftermarket clutch pedal? That seems excessive to me.
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Old Jul 30, 2016 | 08:46 AM
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Spring for the RJM pedal (pun intended), and you'll be very happy. I've been driving only manual transmission cars for 42+ years, and the RJM pedal transformed the clutch on my Z to something I really enjoy. Well worth the $249. Get one quick, as this is the last batch that's going to be made.
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Old Jul 30, 2016 | 11:57 AM
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Your slave took a dump on you
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Old Jul 30, 2016 | 12:44 PM
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Not necessarily. I think the clutch pedal is misadjusted.
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Old Jul 30, 2016 | 12:56 PM
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Possible, but if its never been touched i doubt it. We shall see in time... his symptoms mimicked mine exactly
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Old Jul 30, 2016 | 12:57 PM
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Edit.. reread everything and yeah its possible is misadjusted
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Old Jul 31, 2016 | 05:14 AM
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There's a fluid control valve in the master cylinder. It's purpose is to replenish fluid in the cylinder and lines should fluid bypass the seals. This becomes more a concern as the system wears.

Adjusting pedal engagement at the threaded yoke pushes the piston in the M. C. forward, there is a small range of adjustment available before that port is closed by the valve. At that point, fluid from the reservoir will no longer flow to refresh the lines. Hydraulic pressure falls to the point that the pedal will eventually go to to the floor before actuating the slave cylinder.

Illustration:

http://www.aa1car.com/library/brake_master_cylinder.htm

Last edited by timeltel; Feb 4, 2017 at 10:17 AM.
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Old Jul 31, 2016 | 10:25 AM
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So basically where I left off at the OP I adjusted the pedal higher in the morning due to the clutch being stuck engaged and the after work it lowered again but basically to where I want (right off the floor engagement.). It has bot changed by itself since then. Is it okay for me to leave it like this or can it cause damage ? I feel no resistance shifting gears so clutch is not partially engaged with the clutch down and the clutch doesn't slip at all when in gear so it's fully engaging when off the clutch.
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Old Jul 31, 2016 | 02:00 PM
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I asked Ryan (the guy who makes/sells the RJM adjustable pedal) about this once. and my impression is that you run the risk of overextending the slave cylinder, which can cause damage. That's the point of the RJM pedal - you can adjust the pedal height and release point to your preference without damaging the cylinders, which should extend their life.
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Old Aug 1, 2016 | 06:20 PM
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Originally Posted by dcains
I asked Ryan (the guy who makes/sells the RJM adjustable pedal) about this once. and my impression is that you run the risk of overextending the slave cylinder, which can cause damage. That's the point of the RJM pedal - you can adjust the pedal height and release point to your preference without damaging the cylinders, which should extend their life.
Well I missed out on the final group buy because I dropped $900 on art pipes and resonated xyz pipe so hopefully my clutch height is fine how it is lol. It shifts so much better adjusted this low. How sport cars are supposed to shift.
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