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Discussion Starter · #21 ·
This is written for and directed at persons who have a general understanding of common hand tools (including automotive related). It also assumes the person has, or has access to, the necessary tools to complete the job. You can refer to my pictures for visual reference.

This is how to 1/2-ass it. I would suggest you remove the CDD completly and replace it with a hard line/connectors.

Of course, this is done at your own risk. I assume no responsibility for you choosing to modify your car. Yes, I am sure this will void your warranty.

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Part I – Remove, extract internals, and replace the CDD
Open your hood and locate the Clutch Dampening Device (CDD). It is located on the drivers-side, next to the firewall.

Place a cloth under the CDD and the lines that run into it (you DO NOT want to get any fluid on paint or other surfaces). Unscrew the two lines that enter the right and left side of the CDD. There should not be much, if any, fluid that drips out of the lines.

Unscrew the bolts that hold the CDD to the car frame. Be careful when you pick up the CDD because fluid will probably drip out.

Take the CDD to your work area and use your 27mm socket to remove the brass end cap. Pull or shake out the internals. Screw the brass end cap back on.

Using the two bolts, bolt the CDD back on the car frame.

Screw the two lines back into their respective ends. Make sure you do not over tighten/strip these screws.

Part II – Bleed the line
Look down through the engine and locate the red part sticking off the side of the drivers-side of the transmission. You will see a bleeder screw. This is what you need to get access to.

Jack up the front of the car and place jack stands under it. If you are using a floor jack, you can place the jack under the front, in the middle, on the metal plate (all the rest is plastic covered). Place the jack stands on the frame just behind the front wheels (NOT where the spare tire jack would go).

Under the drivers-side of the car, remove the necessary screws that enable you to remove or pull out of the way the plastic crap (about 5/6 screws). Some of these are not conventional screws, but fasteners that require a “unscrew” then a “pop”.

Pull the cap off the clutch reservoir (mounted to the firewall, behind the CDD). Go under the car and hook up the bleeder hose to the bleeder screw. If you bought the $50 pump bleeder tool…life is easy. If you bought the $6 gravity bleeder…life is harder. Loosen the bleeder screw. Bleed the line, being sure never to let the reservoir empty. You will suck down a good portion of a new bottle of fluid (uses brake fluid). Tighten the bleeder screw and remove your bleeder hose.

Part III – Put your car back together
Now put your car back together…by doing everything in reverse (I always wanted to say that). :) :)
 
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since i dont know how to do it myself, i have a tech guy and shop what do i tell them to fix the probelm, i should say the clutch....BLANKS and you guys need to BLANK....fill in the BLANKS with what them should do.... please....would replacing the clutch itself fix them problem or is it more detailed.....
 

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Discussion Starter · #24 ·
LexIS307 said:
since i dont know how to do it myself, i have a tech guy and shop what do i tell them to fix the probelm, i should say the clutch....BLANKS and you guys need to BLANK....fill in the BLANKS with what them should do.... please....would replacing the clutch itself fix them problem or is it more detailed.....
ONE - This is not a PROBLEM. It was designed this way by Lexus engineers. The clutch is working properly when it does what I described in my original post.

TWO - Why would you pay money to have a person alter something that you have no clue as to what the benefit (posible) is for you (the driver)? If you understood this topic,you would not have posted the question you did.

Can you say..."jumping on the mod bandwagon"...??
 

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Can I pick up a hard line to replace the CDD at the local parts store?

Anyone lnow?
 

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great post redline! although i have some questions,

1. after you go through this process of removing the CDD, does the clutch get more sensitive(less stiff)? or is the slow release just removed?
2. how much should i bleed the fluid?
3. is the vice really necessary? is it really hard to remove that brass nut?
4. how long did this process take?
 

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aka_Altezza said:
great post redline! although i have some questions,

1. after you go through this process of removing the CDD, does the clutch get more sensitive(less stiff)? or is the slow release just removed?
I believe I can answer this question. This is just what I have gathered from reading Redlines original post...so dont quote me on it. I'm pretty sure that removal of the CDD will not effect the throw/stiffness of the actual clutch, but will allow the RPMs to fall immediately after engaging the clutch, rather than having them hang there after pushing in the clutch? This should allow for quicker shifts and let the RPM fall lower than before when shifting.
 

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Discussion Starter · #28 ·
aka_Altezza said:
1. after you go through this process of removing the CDD, does the clutch get more sensitive(less stiff)? or is the slow release just removed?
Kinda like sex...great feeling, but hard to put in words :lol:
Seriously, I will try to explain it best I can. Put the movement of the clutch pedal on a 1-10 scale. 1 = pressed to the floor & 10 = foot off, all the way up.
Stock - casual driving (low rpm launch)
1,2,3 = No engagement yet (play)
4,5,6,7 = Gradual engagement to full engagement
8,9,10 = No engagement (play)

Stock - lead foot driving (high rpm launch)
1,2,3 = No engagement yet (play)
4,5,6 = Engaged, but power is limited because...
7 = Your foot is off pedal, it "sticks/hangs" (limited engage)
8,9,10 = When your rpms drop, the pedal will spring to the top on its own (fully engaging).

Altered CDD - casual and lead foot
1,2,3,4 = Gradual engagement to full engagement
5,6,7,8,9,10 = Play

aka_Altezza said:
2. how much should i bleed the fluid?
Until you no longer see any air bubbles comming out and into your clear bleeder line. It is really a personal judgement call (better to be based on experience). You will know right away is there is any air in the line. The pedal will be soft...and it might not even spring back to the top.


aka_Altezza said:
3. is the vice really necessary? is it really hard to remove that brass nut?
The vice was because I originally ws using a crescent wrench (POS). My socket set did not go large enough. You could use a crescent wrench to hold the green (main) section and use the socket to unscrew the brass end cap. I got pissed because I could not get my wrench to open it...so..out came the hammer... :bitching: I do not suggest you follow my lead here.

aka_Altezza said:
4. how long did this process take?
I cannot say because I had to stop in the middle and ride my mt. bike (cause my car had no working clutch...) to Sears and buy my 27mm Craftsman socket. I wasted more time exploring the part and such. If I were to guess...1.5/2 hrs?

If any of my technical explanations are incorrect, would the tech folks please chime in and correct me. I don't want to mislead anyone.
 

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So basically, without the CDD, we should be able to drop the clutch from high rpms at a standstill?

Just to clarify that this is what you all are getting at...


BTW, the repair manual says that part is the Clutch Release Cylinder.
 

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What would happen if you didn't bleed the line, and simply replaced the CDD minus its internals?
 

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the next time you pushed on the clutch pedal, it would sink to the floor and not spring back up. you also wouldn't be able to move in and out of gears without grinding, because your slave cylinder wouldn't be functioning.

-gte





DJPoop said:
What would happen if you didn't bleed the line, and simply replaced the CDD minus its internals?
 

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Thanks....guess thats a pretty important step, not to be skipped. Thanks again.

IS300GTE said:
the next time you pushed on the clutch pedal, it would sink to the floor and not spring back up. you also wouldn't be able to move in and out of gears without grinding, because your slave cylinder wouldn't be functioning.

-gte





DJPoop said:
What would happen if you didn't bleed the line, and simply replaced the CDD minus its internals?
 

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This may be a silly question, but once I bleed the line, do I have to replace the fluid? How do I put it back it?
 

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redline814 said:
Altered CDD - casual and lead foot
1,2,3,4 = Gradual engagement to full engagement
5,6,7,8,9,10 = Play
Are you trying to say that this mod altered the clutch engagement point? Would this be the effect of having a different volume of fluid in the system due to bleeding and the clutch engagement point can/should be adjusted after bleeding the line?
 

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Discussion Starter · #35 ·
inphinit said:
So basically, without the CDD, we should be able to drop the clutch from high rpms at a standstill?

Just to clarify that this is what you all are getting at...


BTW, the repair manual says that part is the Clutch Release Cylinder.
Yup...that is what I was getting at (in a long winded kinda way).

Awe man...now I have to go and change the name to --> CRC :lol:
 

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Discussion Starter · #36 ·
TeCKis300 said:
Are you trying to say that this mod altered the clutch engagement point? Would this be the effect of having a different volume of fluid in the system due to bleeding and the clutch engagement point can/should be adjusted after bleeding the line?
You are probably correct, but that is over my car technical know-how. Can anyone elaborate IF it can be or IF it needs to be or HOW it is adjusted?
 

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Discussion Starter · #37 ·
DJPoop said:
This may be a silly question, but once I bleed the line, do I have to replace the fluid? How do I put it back it?
Yup, silly indeed :) The difference is a working clutch and a non-working clutch.

You are sucking the fluid from the top (reservoir)...down thru the line...and out the lowest point in the line (bleeder screw). You are not necessarly "replacing" the fluid. You are "cycling" the fliud thru the line (pushing the air out the bottom), hence the need to keep adding new fluid.

Think of air as the enemy.
Before removal - Top-->--Line-->--Bleeder
During removal - Top-->--Break+Air-->--Bleeder
After Bleeding - Top-->--Line-->--Bleeder

When you opened the line, you let air into the line. You are removing this air. You cannot ever let the top reservoir run below the lower fill line (I used the fill line because it is the only reference point I could get folks to identify with). If it runs empty, and you pour more in, you just poured fluid on top of air. This just introduced air back into the line...the exact reason for bleeding the line in the first place.
 

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That explains a lot. Thanks!
 

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it has a differnent engagement point, volume increase is almost nil. there shouldn't be a need to have to adjust the engagement point (which is really just pedal height because it is hydraulic) if it was ok to start out with

-gte






TeCKis300 said:
redline814 said:
Altered CDD - casual and lead foot
1,2,3,4 = Gradual engagement to full engagement
5,6,7,8,9,10 = Play
Are you trying to say that this mod altered the clutch engagement point? Would this be the effect of having a different volume of fluid in the system due to bleeding and the clutch engagement point can/should be adjusted after bleeding the line?
 

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have an experienced mechanic watch over you while you do this mod and you'll be fine, he'll be able to guide you through it, and show you visually as well. btw, clutch fluid is corrosive to paint, be careful

-gte






DJPoop said:
That explains a lot. Thanks!
 
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