Clutch Delay Valve for the XI

[kwakr738]

Saw this post: http://www.e90post.com/forums/showthread.php?t=132509

Any idea how a CDV works?

[E91 Dude]

http://www.zeckhausen.com/CDV.htm

[kwakr738]

Awesome link!! Thanks.

[BavarianBullet]

Perhaps you missed my earlier rant on the 335XI and the CDV: http://www.e90post.com/forums/showthread.php?t=154713

The short summary re 335XI and the CDV is that it's a little bit more of a PITA than on a 335i because there is a driveshaft in the way when you go to bleed the air out of the hydraulic system. Prob a 30-40min job if you've done one before, a bit longer if you're not mechanically talented and haven't done one.

FWIW I personally wouldn't buy a modified CDV- you can simply just remove it for free, put it on a shelf and just clip the two lines back together again. You're not going to fool the dealer techs because the car will clearly drive totally different and there will be enough marks on the POS plastic bleeder screw on the slave cylinder to tell them you worked on it if they care to check.

It's well worth doing however- you can't even begin to compare how much better the car will drive (ie like a "normal" manual trans car).:thumsup:

[jpsimon]

I ordered a modified cdv from riss-racing last week. i can't wait to get it in this week!! i absolutely despise that damn CDV. "clutch delay valve"... why does that even exist??? those words shouldn't be in the same sentence.

[RBBMWE46M3]

I ordered a modified cdv from riss-racing last week. i can't wait to get it in this week!! i absolutely despise that damn CDV. "clutch delay valve"... why does that even exist??? those words shouldn't be in the same sentence.

Let us know how the installation goes!!!!:thumsup:
I'm gunna get one too, very soon

[jpsimon]

We're not gonna bleed the system, we're going to clamp the line closed, then un-clamp it when the modified valve is put in! much easier!

[NatesGr8]

We're not gonna bleed the system, we're going to clamp the line closed, then un-clamp it when the modified valve is put in! much easier!
+1000 bleeding ftl, we'll just see how it goes with pumping the clutch pedal/brakes a few times. If bleeding still seems necessary then i'll do it.

[halB]

We're not gonna bleed the system, we're going to clamp the line closed, then un-clamp it when the modified valve is put in! much easier!

Somehow you still have to get rid of the air pocket that comes inside the new valve.

[noire07]

Anybody know whether the Riss cdv feel different from no cdv at all? I've been driving around with no cdv for about a year now and love how it feels. I just ordered the cdv just so I could have something under there, just so it looks like stock (yeah i know, the tech will probably feel the difference anyways, but it makes me feel better. They haven't said anything the last time I went in though).

Just wondering so I know what to expect.
Thanks

[18LLC]

i just completely remote the cdv for my xi about 2 years ago. NOT pita at all. cost me $20. I gave the shop the "i" version cdv removal instruction, and they say my xi looks the same.

[David1]

I have done a bunch of these now and you must bleed the system. Even clamping the line you introduce air into the slave. Once you bleed it it will fell even better. If you have a bunch of play at the top of the pedal stroke, you have an air bubble. I have been working on cars for 30 years and you always have to bleed any hydraulic system once opened. You may only get a small amount of air in there, but it is there. And I will tell you this, this car is the worst to bleed the clutch! No room and the slave bleed points at a bad angle to bleed it. They guys at the factory must be joking about how to bleed it once installed in the car. It took me 5 minutes to remove the valve and 30 minutes to bleed and a full pint of fluid. If the car is not level, you will not be able to bleed it since the bleeder points down and and is on the rear of the slave cylinder and if you have the front raised up, well you get the picture.

[Dragonman4]

I have done a bunch of these now and you must bleed the system. Even clamping the line you introduce air into the slave. Once you bleed it it will fell even better. If you have a bunch of play at the top of the pedal stroke, you have an air bubble. I have been working on cars for 30 years and you always have to bleed any hydraulic system once opened. You may only get a small amount of air in there, but it is there. And I will tell you this, this car is the worst to bleed the clutch! No room and the slave bleed points at a bad angle to bleed it. They guys at the factory must be joking about how to bleed it once installed in the car. It took me 5 minutes to remove the valve and 30 minutes to bleed and a full pint of fluid. If the car is not level, you will not be able to bleed it since the bleeder points down and and is on the rear of the slave cylinder and if you have the front raised up, well you get the picture.

You don't need to bleed it. Might be a good idea to make sure, but not absolutely necessary. I had my CDV done by Alex (HyperM3) a little while after I got my car in March or so. Took him a little over 10 minutes to swap it out. It is a little harder to do than the 335i, but still easily doable. Alex just clamped down my line. After that, I just cycled through my brake and clutch a few times, and off I went. I was the 1st xi that he did as well so he didn't have any prior experience w/ them, but he has done a crapload of normal 335i CDV's plus fender rolling. That's why he's Tri-state's resident mod installer guy.

[JeffL]

I did bleed mine as the clutch and brake pedal did not feel right after I was done. The air from the new CDV is going to get into the system. I have huge hands and the only way I could get to the bleeder valve without destroying it was to remove the front drive shaft. Was a PITA but well worth it. Power shifts and speed shifts are the way they should be now.