Fk8 4343
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The clutch delay valve is located inside of the clutch slave cylinder to slow down the engagement of the clutch to reduce shock to the drivetrain. With correct clutch control, the CDV is not needed. Instead it interferes with the operation of the transmission.
My certified pre-owned 2016 V6 Accord 6spd MT had a clutch that always felt direct, in control and with feedback from the drivetrain. By comparison, the CTR felt numb. The first owner removed the CDV from the Accord.
CDV removal on the CTR is easy with the exception of one hard step: removal of a metal retaining ring to get the CDV out. The ring needs to be in one piece so you can put the slave cylinder back together. It took me 45 minutes to get off .
Damaging the inner walls during extraction of the CDV is possible and you would not be able to drive the car until the broken cylinder is replaced. If you first order a new slave cylinder and remove the CDV, then you will get the hardest part the done first.
@Acurately posted pictures of opening the slave cylinder.
https://www.civicx.com/threads/the-infamous-2nd-gear-crunch.12890/page-43#post-362120
@gylmar814 Has a write-up for CDV removal on the Si and an explanation of what the CDV does and why you may want to remove it.
https://www.civicx.com/threads/clutch-delay-valve-delete-prl-ss-clutch-line-install-review.21587/
@PRL Motorsports has another write-up for CDV removal.
https://www.civicx.com/threads/10th-gen-civic-1-5t-clutch-delay-valve-removal.13105/
There are a lot of youtube videos on CDV removal for Honda MT. Previous gen civics and Accords have the same CDV. This video explains a technique to get the ring off and something similar worked for me.
Recommended tools for opening the cylinder:
Vice and clamps – hold the cylinder with the ring end up
Tekton pick and hook set – retainer ring removal
Needlenose pliers with teeth – pull out the plug
Drill and drill bits (1/16”, 1/8”, 3/16”) – CDV extraction
It is important to be careful once the cylinder is open. Scratching the inner wall of the cylinder can cause a fluid leak so don't use the needle nose pliers to extract the CDV. I pulled the CDV out by drilling into it and getting the drill bit lodged inside. Started drilling with a 1/16” bit and then 1/8” to widen the hole. Then I took a 3/16” bit and twisted it into the hole by hand using pliers. The bit got stuck and then pulled out the CDV.
Slave cylinder removal and installation
Part 1: Remove the air box.
Mishimoto has a video showing the removal of the airbox for their performance intake installation.
Unplug MAF
Remove rubber air duct and loosen bolts
You don't need to remove all the rubber stripping like in the video, only the part holding the air duct down.
Remove intake tube
Remove air box
The air box can be opened and taken apart if it makes it easier to get out. The rubber air duct also comes off. The air box clips into a bracket on the bottom.
Part 2: Remove clutch slave cylinder
First, locate the slave cylinder, clutch hydraulic line and all of the components listed below. See Parts diagram for numbers.
Slave cylinder (7)
Steel tube (18)
Rubber hose (15)
Bracket (17)
Nut (23)
First find the slave cylinder.
The slave cylinder (7) is attached to a steel tube (18). The other end of the steel tube connects to a rubber hose (15) that is mounted at bracket (17) using nut (23).
Do not bend the steel tube. Remove the nut indicated by the arrow and unclip the bracket to take the tension off of the steel tube. Now unbolt the slave cylinder from the transmission. Slip the slave cylinder out from behind the water hoses and pull it up. The rubber hose is long enough that you can pull the slave cylinder to the top of the engine bay. I tied the end of the steel tube near where the intake was so that fluid didn't drip out after removing the slave cylinder. Remove the slave cylinder using 2 open ended wrenches.
Connect the slave cylinder (with CDV removed) to the hydraulic line. Put the slave cylinder back onto the transmission case, clip the hydraulic line bracket and secure with the nut. Torque the slave cylinder bolts to 16 ft lbs.
Bleeding
Thanks to @Acurately for clutch bleeding procedure
https://www.civicx.com/threads/clutch-fluid-brake-fluid-reservoir.11380/#post-365829
Put a 8mm box end wrench over the bleeder screw and then attach a ¼” plastic tube. Follow bleeding procedure. Have someone sit in the driver seat to operate the clutch while you loosen/tighten the bleeder screw.
1. Loosen the bleeder screw.
2. Push clutch pedal in. The displacement of the fluid from moving the pedal will push the air out of the cylinder.
3. Tighten the bleeder screw.
4. Release clutch pedal. Pull it up from the floor it does not come back on its own.
5. Repeat. Make sure brake fluid does not go below minimum level.
My certified pre-owned 2016 V6 Accord 6spd MT had a clutch that always felt direct, in control and with feedback from the drivetrain. By comparison, the CTR felt numb. The first owner removed the CDV from the Accord.
CDV removal on the CTR is easy with the exception of one hard step: removal of a metal retaining ring to get the CDV out. The ring needs to be in one piece so you can put the slave cylinder back together. It took me 45 minutes to get off .
Damaging the inner walls during extraction of the CDV is possible and you would not be able to drive the car until the broken cylinder is replaced. If you first order a new slave cylinder and remove the CDV, then you will get the hardest part the done first.
@Acurately posted pictures of opening the slave cylinder.
https://www.civicx.com/threads/the-infamous-2nd-gear-crunch.12890/page-43#post-362120
@gylmar814 Has a write-up for CDV removal on the Si and an explanation of what the CDV does and why you may want to remove it.
https://www.civicx.com/threads/clutch-delay-valve-delete-prl-ss-clutch-line-install-review.21587/
@PRL Motorsports has another write-up for CDV removal.
https://www.civicx.com/threads/10th-gen-civic-1-5t-clutch-delay-valve-removal.13105/
There are a lot of youtube videos on CDV removal for Honda MT. Previous gen civics and Accords have the same CDV. This video explains a technique to get the ring off and something similar worked for me.
Recommended tools for opening the cylinder:
Vice and clamps – hold the cylinder with the ring end up
Tekton pick and hook set – retainer ring removal
Needlenose pliers with teeth – pull out the plug
Drill and drill bits (1/16”, 1/8”, 3/16”) – CDV extraction
It is important to be careful once the cylinder is open. Scratching the inner wall of the cylinder can cause a fluid leak so don't use the needle nose pliers to extract the CDV. I pulled the CDV out by drilling into it and getting the drill bit lodged inside. Started drilling with a 1/16” bit and then 1/8” to widen the hole. Then I took a 3/16” bit and twisted it into the hole by hand using pliers. The bit got stuck and then pulled out the CDV.
Slave cylinder removal and installation
Part 1: Remove the air box.
Mishimoto has a video showing the removal of the airbox for their performance intake installation.
Unplug MAF
Remove rubber air duct and loosen bolts
You don't need to remove all the rubber stripping like in the video, only the part holding the air duct down.
Remove intake tube
Remove air box
The air box can be opened and taken apart if it makes it easier to get out. The rubber air duct also comes off. The air box clips into a bracket on the bottom.
Part 2: Remove clutch slave cylinder
First, locate the slave cylinder, clutch hydraulic line and all of the components listed below. See Parts diagram for numbers.
Slave cylinder (7)
Steel tube (18)
Rubber hose (15)
Bracket (17)
Nut (23)
First find the slave cylinder.
The slave cylinder (7) is attached to a steel tube (18). The other end of the steel tube connects to a rubber hose (15) that is mounted at bracket (17) using nut (23).
Do not bend the steel tube. Remove the nut indicated by the arrow and unclip the bracket to take the tension off of the steel tube. Now unbolt the slave cylinder from the transmission. Slip the slave cylinder out from behind the water hoses and pull it up. The rubber hose is long enough that you can pull the slave cylinder to the top of the engine bay. I tied the end of the steel tube near where the intake was so that fluid didn't drip out after removing the slave cylinder. Remove the slave cylinder using 2 open ended wrenches.
Connect the slave cylinder (with CDV removed) to the hydraulic line. Put the slave cylinder back onto the transmission case, clip the hydraulic line bracket and secure with the nut. Torque the slave cylinder bolts to 16 ft lbs.
Bleeding
Thanks to @Acurately for clutch bleeding procedure
https://www.civicx.com/threads/clutch-fluid-brake-fluid-reservoir.11380/#post-365829
Put a 8mm box end wrench over the bleeder screw and then attach a ¼” plastic tube. Follow bleeding procedure. Have someone sit in the driver seat to operate the clutch while you loosen/tighten the bleeder screw.
1. Loosen the bleeder screw.
2. Push clutch pedal in. The displacement of the fluid from moving the pedal will push the air out of the cylinder.
3. Tighten the bleeder screw.
4. Release clutch pedal. Pull it up from the floor it does not come back on its own.
5. Repeat. Make sure brake fluid does not go below minimum level.
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