DIY: CDV (Clutch Delay Valve) removal

[dough boi]

I searched for a guide but didn't find one, so hoping this helps someone later on. This was done in a 335i Coupe had right around 900 miles on it when I did this.

Should take about 30mins to an HR.

Tools needed:
-10mm Socket wrench, for the under panel
-11mm open end wrench, don't bother using a flare wrench mine didn't fit and the bleeder valve is not torqed hard enough to need one anyways. I also used a pair of pliers to help with the bleeder valve.
-A small allen wrench (I don't remember the size I used but it is very small) this is to loosen the bleeder valve.
-Needle nose pliers or a pocket knife to remove clips on CDV
-Locking wrench or vice grip, for clamping the soft line
-Jack and jack stands and wheel chocks
-Small tube to attach to bleeder valve.
-One 12oz bottle of DOT4 brake fluid

I didn't take pics when I did it. Wasn't my car and I didn't do it at home and forgot to bring my camera with me. It was pretty easy and straight forward.

First, jack up the car as necessary, I found it easiest to jack it up from the crossmember, you will see a rectanglar spot of metal that sticks through the under panel at the crossmember. Then putting jack stands on the jack points by the door behind the front tire, which will be a retangular plastic piece. Leave it in gear with the e-brake engaged and chock the rear tires.

2. With a 10mm socket wrench. Remove the underpanel covering the end of the bell housing. There will be three different panels down there. One covering the oil pan, one covering the bellhousing, and one right where the guibo connects to the driveshaft. This will make perfect sense once you are underneath the car. The one you remove will be the middle one. I took off the one farthest from the back first then realized I didn't have to.

3. Locate the clutch delay valve. I've attached a picture of where it is and what it looks like. These are not my pictures and are some I pulled from another site. Compliments of EvanL on e90 post. From the bottom of the car locate the end of the bellhousing and it will be sitting right there attached to the brake lines on the drivers side of the bellhousing. It is held attached to the car by a thin metal bracket (which you will not have to remove from the car).

4. Once you have located the clutch delay valve you will see two paperclip like clips on each side (with the bracket in the middle). Pry these off carefully as you will need to reuse them. Once these clips are off the valve is ready to be removed. I found it to be easier to remove the one towards the rear of the car first, then removing the one nearest to the front after. Keep in mind these clips come off differently you will see once you get there, both are relatively easy to remove I pryed them off using my pocket knife. DO NOT REMOVE THE VALVE YET.

5. Clamp the soft brake line with a locking wrench, I used a vice grip. Wrap a towel or cloth around the line before clamping it to avoid damage to the line. I clamped it about 3 inches from the end of the line. This is to avoid losing too much fluid, helps when you have to bleed the brakes.

6. Remove the clutch delay valve, it should easily pull off the brake lines.

7. Depending on whether you are completely removing it or replacing it with a modified one (which I did) either connect the two lines without the CDV in the middle, or reverse install the new valve. The two lines will mate up to each other perfectly so don't worry about it, if you are removing completely. The valve is now replaced.

8. Bleed the clutch. The reservoir is shared between the clutch and brake system. This is located underneath a plastic panel next to the windshield wiper on the drivers side. You do not need to remove the micro filter to get to this. There are three panels when you look, a small one on each side and a big one in the middle, this is the far left one. The big middle one is for the micro filter.

Bleeding the clutch is pretty straight forward, if you have a speed bleeder (vacum bleeder) I don't think you need me to tell you how to do this.

My bleeder valve was made of plastic. IT IS VERY FRAGILE. Use the allen head to loosen the valve then use the open ended wrench to loosen and tighten it when you are bleeding. This space is very tight, very hard to reach into, I tried with my flare wrench and didn't get it to work. used an open ended wrench, worked perfect.

I won't get into how to bleed it. I believe you can find articles on bimmerdiy.com for bleeding instructions. But essentially, open valve->depress clutch, close valve->release clutch. Repeat until no more air comes out of the tube attached to the bleeder valve. Check reservoir and fill accordingly.

So, sorry about not taking pics, I tried to be as thorough as I can. It's 3am and I finished it about an hr or two ago.

I will attach pics in my next post. This is a very easy job, did it without having any experience with any CDV. I can turn a wrench though, and even so it should be an easy job for anybody with basic knowledge.

[dough boi]

These will show what the CDV looks like and where it is located, it will also show the metal bracket the the clips are on eash side of. Again these are not my pics. I pulled these from a post I found AFTER I did the replacement

[dough boi]

In the drawing picture (if that makes sense) it's late, I apologize. #13 is the valve. #12 is the bracket. #15 is the bleeder valve. #18 is the rubber cover that will need to be removed from the bleeder valve.

The picture of with the green arrow points to where the valve should be. The circle shows the bleeder valve. The one with the two thin red circles show the clips that need to be removed.

My bleeder did not look like the one pictured. Mine was black plastic, easily broken.

The rubber soft brake hose is located towards the front of the car.

Hope this isnt too confusing. This is my first DIY post, and I posted a bit after I actually finished it so I don't remember exactly everything and again. It's like 3am and I need to sleep. Wanted to post this while it was still relatively fresh in my mind. Hope this helps somebody. Feel free to comment on how well the post was made if it was helpful. I'd very much like the feedback but please constructive criticism only.

[Beer Goggles]

Looks like a lot of detail....although forgive my stupidity, but why did you do this, and what does it do?

[greenie99]

How did you get the car to stand on its front end?????

[GatorM]

How did you get the car to stand on its front end?????

Offered it a treat.

[thekurgan]

Looks like a lot of detail....although forgive my stupidity, but why did you do this, and what does it do?

BMW places this valve inline with the clutch to delay the engagement of the clutch, I suppose, to save driveline shock. Experienced drivers find it very annoying, esp when parallel parking and shifting at high rpms.

This mod is very welcome!

[Beer Goggles]

BMW places this valve inline with the clutch to delay the engagement of the clutch, I suppose, to save driveline shock. Experienced drivers find it very annoying, esp when parallel parking and shifting at high rpms.

This mod is very welcome!

I sort of implied that from the name of of it...that would also explain why I feel like an idiot when shift sometimes. I thought it was just my timing.

[thekurgan]

I sort of implied that from the name of of it...that would also explain why I feel like an idiot when shift sometimes. I thought it was just my timing.

Hee hee, I agree. I don't believe the "M" series has it, as the M3 I drove felt really nice, but the 550 had it for sure, felt like I was stripping the clutch:

"It's normal", said the salesperson
"It sucks", said I

[dough boi]

How did you get the car to stand on its front end?????

You would want to jack the car up from the crossmember which is around the oil pan area towards the front of the car. When you look underneath you will see on the underpanel there is a rectangle opening with metal showing through, that is the jack point for the front of the car. Jack it up from there until it is high enough to place jack stands on the side jack points. These are by the side skirts under the car just about where the front door starts. These will be rectangle plastics 'pads' you will see it when you look underneath the car.

thekurgan:
96+ M3's should have it. E46 included. I owned a '96 that had it, and I've driven serveral E46 that had it. Helped with the removal of one on a E46. The E46 one isn't as bad though you really only feel it when shifting high and trying to shift quick. I felt it most when I was heel-toe downshifting.

beergoggles: Look into replacing this with a modified piece. That way when you car is at the dealership them won't know that you've modified anything. Night and day difference when shifting. Before when I drove his car I was a little unsure of myself when shifting it was like I had to think about it to do it right. I've been driving standard shift cars for the past 5 years. I'm usually comfortable with driving ANY standard car. But his I couldn't get any type of feel for the clutch, after the CDV removal it felt great like driving my own car.

[greggmorton]

Hee hee, I agree. I don't believe the "M" series has it, as the M3 I drove felt really nice, but the 550 had it for sure, felt like I was stripping the clutch:

"It's normal", said the salesperson
"It sucks", said I

Apparently from what I have read that it is standard on all MT BMWs.

[Blue330i2006]

I am going swap mine this weekend. will elaborate when finished.

[Blue330i2006]

AAAAAAAAAAAAAAAAAHHHH. SO MUCH BETTER!

Took me 37 min from first grabbing the jack to putting the jack away. So easy.
Best 30$ spent on the car.

[Danny 335i]

its the samething they put in the Evo,s. Its called a restricter pill in the evo. It goes in the clutch slave cylinder and restricts the flow of fluid so that the clutch slips at high rpm launches so as not to shock the drivetrain and blow up your transfer case. The first thing i did with both my evo,s after i bought them was to remove the pill and put a stainless steel clutch line on.Made a huge difference.The clutch grabbed at the same point everytime,the pedal wasn,t as mushy,and you got a much better launch.I dont know why BMW would put one in a non awd car if thats what is in this post.In an awd its obvious why they would do it,but it shouldnt be in a open diff or even a lsd diff. Saftey,Saftey huh?BTW where did you get the modified valve. Also is the new valve same as the stock one just without the res. in it.

[dough boi]

Danny, from what I gather it basically acts as an idiot proof, protect the tranny with the price of a clutch. Makes enough sense to me. From what you said about the evo one, sounds pretty much like its the same exact thing used for the same reason. Something that came standard on all BMW MT cars since OBDII I believe.

As far as replacement of it, you can easily remove it completely, I outline this in DIY, but from what I understand this is something the dealership will most definately check before working on a car for a warranty claim. There is a website that sells a "dummy" unit, which is a stock valve. Its exactly a stock valve but modified to have nothing in the internals, nothing to restrict clutch fluid movement in the lines. I think it was something like zeckhausen or something along the lines of that. I think bavauto also sells a similar valve. Seems to be the best bet to get a modified one, my buddy got his from zeckhausen(?). I wouldnt go and get rid of it completely when the modified valve is so cheap.

[dough boi]

AAAAAAAAAAAAAAAAAHHHH. SO MUCH BETTER!

Took me 37 min from first grabbing the jack to putting the jack away. So easy.
Best 30$ spent on the car.

Did you use the write up? If so, care to comment on my write up at all?

[Blue330i2006]

Did you use the write up? If so, care to comment on my write up at all?

Good write up. I used yours and the one on E90 post. What yours helped most was the jacking point and to remind the reader to crimp the line so not to lose fluid. Only took me 3 clutch actions to bleed out all air and didn't even have to add fluid.

Use dot IV though for fluid not III as stated on the reservoir. or check your reservoir and add what it says to add.

Thanx for the write up, and I got my "valve" from Zeckhausen racing for 30$.

[Danny 335i]

In the evo,s the res. pill in the slave cylinder was just a small plastic piece that was easily removed. You just opened the cylinder and took it out and put everything back together. I guess its different in the BMW because the restricter is the whole piece. In the evo there was no way for the dealer to know it was removed unless they took the slave cylinder out and checked,which they wouldnt have any cause to do. Do you have a sight or phone number where we can get the stock looking piece without the res. internals. BTW,great post on this subject.Its the little things that make a big difference.

[gloster]

I would be very interested to hear killcrap's comments (or the other BMW techs on the board) on this issue. What kind of danger do you think we are/are not creating with this mod? Why do you think BMW puts it on? I've heard the standard enthusiasts theories and comments, but would love to hear a trained tech's take on it.

[dough boi]

Good write up. I used yours and the one on E90 post. What yours helped most was the jacking point and to remind the reader to crimp the line so not to lose fluid. Only took me 3 clutch actions to bleed out all air and didn't even have to add fluid.

Use dot IV though for fluid not III as stated on the reservoir. or check your reservoir and add what it says to add.

Thanx for the write up, and I got my "valve" from Zeckhausen racing for 30$.

Right, sorry about that, I'm so used to DOTIII fluid that I probably just typed it in without even realizing it. Thanks for catching that.

[red335]

Looks like a lot of detail....although forgive my stupidity, but why did you do this, and what does it do?

+1.

Nevermind, saw the post above.

[JM9517]

I've had a MT 335i coupe since October 06. Upon taking delivery of the car I was new to driving a MT. However, after having learned and practiced on friends cars some years before, I picked it up pretty easily. I always felt (and still do) as though everytime I step in to drive the car the clutch has a different catch point. Until reading all of your comments, I chalked it up to my inexperience in driving a MT. Is the different catch point a result of the Clutch Delay Valve?

[Danny 335i]

I've had a MT 335i coupe since October 06. Upon taking delivery of the car I was new to driving a MT. However, after having learned and practiced on friends cars some years before, I picked it up pretty easily. I always felt (and still do) as though everytime I step in to drive the car the clutch has a different catch point. Until reading all of your comments, I chalked it up to my inexperience in driving a MT. Is the different catch point a result of the Clutch Delay Valve?

Yes! If you read my post you will see where i said that after removing the res. pill from the slave cylinder,which is basically the samething as the delay valve,that my clutch grabs at the same point everytime i drive the car.So its not you,its the way the system was built.

[dough boi]

When I first drove the 335 it felt very foreign to me as if I had been lacking manual shift experience.... but I don't I've been driving manuals for the last 4+ yrs.... it felt like I couldn't drive smoothly.... clutch had no feel and was very inconsistent. I was harder to drive than my old RX-7 with a 6 puck ceramic unsprung clutch. Immediately after doing the removal it was a world of diference.. I drove it great felt like any other car I've driven I shifted perfectly smoothly.... didn't have to put any type of thought into it... clutch grabbed at exactly the same point everytime. By the way this isn't my car... so I never got a chance to 'get used to it' First time I drove it.... very very foreign hard for me to drive well... 2nd time about 2 weeks later after doing the removal felt great like I was in my own car. definitely a worth while mod the way I see it.... very inexpensive and easy to do.

[CreeperSleeper]

Is it the same for a 328i? Love the car, hate the clutch...