[Tchao]

*Newer* CDV Delete Method (easier way)

Hey guys, so did the original CDV delete by drilling the restrictor out, but after a year-ish I started leaking brake fluid from the slave-line connection. I think its the o-ring on the hardline that’s leaking but could also be the modified slave too…So I decided to try another route.

The E90 Slave looks exactly the same, and as we all know the E-series BMWs came with an external CDV.
So I went to FCP and got a new E90 Slave + new F30 hardline (I assume is the leaker).

E90 Slave P/N = 21526785964

The F30 lines connects right in!!!

Result/Review:
The clutch is now exactly how my E82 or E30’s felt!
If you’re a 3rd pedal geek, this should be the mod for you. Easier than the drill method, just buy and install.
For the guys who have done the drill method like me, this new slave is a bit better than the drill method. I am now WOT slamming and banging gears with zero slip.

Install pics & details:

• Make sure to open the brake fluid reservoir and suck some fluid out, to prevent over spill when you backwards bleed.
• As you can see, the new E90 slave is restrictor free.
• The hardest part of this is getting to the top nut and then bleeding.
• I took two pics on how I got to the top 13mm nut with my ratchet.
• Once you remove the old slave, use ViseGrips to clamp the line to keep it from leaking when you detach the components.
• Use a large oral syringe (Amazon) and tubing from a brake bleeding kit w/ correct nipple cup.
• Fill the 60cc syringe with 50cc of brake fluid. Use a 11mm wrench to open the bleed valve on the new slave. Slowly push the fluid into the slave while you invert and tilt the slave in all directions to get any bubbles dislodged.
• Keep an eye out on the reservoir to make sure its not overfilling and spilling over.
• Tighten the bleed valve and install the slave.
• Add fluid back to the reservoir if low...
• Pump the clutch pedal...yes it will sink to the floor, pick it back up and vigoriously pump the pedal until it slowly returns to normal. It will take a bit of fast pumping. Once its back to normal, backwards bleed another 50cc into the slave....again be sure the brake reservoir is NOT overfilling (take some out if its full)
• DONE. Grab a beer.

[akgambino]

Nice work!!!

[XutvJet]

Very nice. Thank you for discovering and posting this.

[jparnes1]

I admire your efforts! I completely removed the cdv (not just drill out the restrictor) and haven't had a problem with leaking fluid. The cdv has nothing to do with leaking fluid. Are you sure you had a solid connection between the hard and flexible lines?

[celsdogg]

E30? this makes the clutch feel like an E30?!?! thank you for posting this, it's gonna move to the top of my mod list!

[Eddien123]

You're awesome. Thanks!

[John in VA]

Any idea if a 2015 228i manual has this & if this modification would use the same part? Thanks in advance!

[Tchao]

Originally Posted by jparnes1

I admire your efforts! I completely removed the cdv (not just drill out the restrictor) and haven't had a problem with leaking fluid. The cdv has nothing to do with leaking fluid. Are you sure you had a solid connection between the hard and flexible lines?

I suspect the o-ring on the hardline is the cause, but when I did the drill method originally, and removed everything, my slave was leaking at the connection. So I added the spacer piece back in, and it stopped. So when it leaked again, I just said F it and replace the entire assembly. The spacer def did restrict flow some for sure.

Originally Posted by celsdogg

E30? this makes the clutch feel like an E30?!?! thank you for posting this, it's gonna move to the top of my mod list!

I mean, the F30 will never be as awesome as God's Chariot but the clutch is def near it. 1/2/3 bangs are legit now.

Originally Posted by John in VA

Any idea if a 2015 228i manual has this & if this modification would use the same part? Thanks in advance!

Every manual transmission BMW has this delay valve.
This P/N is also on E-series N20 engines, so I would assume it will work too. Its only $60 to find out.

[MacklinUSOB]

This is the sexiest post I have seen in a while, nice work.

[silver28]

Originally Posted by Tchao

Every manual transmission BMW has this delay valve.

The E39 M5 and E9x M3 actually don't have one.

Regardless, this is an amazing discovering!!! Props to you, I will attempt this in the spring and when I get all those rachet attachments!

[jcarv20]

Damn if you were nearby I'd pay you to do it!

[Tchao]

Originally Posted by silver28

The E39 M5 and E9x M3 actually don't have one.

Regardless, this is an amazing discovering!!! Props to you, I will attempt this in the spring and when I get all those rachet attachments!

Thanks for the info! Not surprising for the E39M, but the E90M was a surprise.
The Wobble Bar is definitely the most useful ratchet attachment Ive ever used. In most situations the swivel joint is too much articulation and PITA with the binding.

Originally Posted by jcarv20

Damn if you were nearby I'd pay you to do it!

It really is easy, took maybe 30mins max, and I am not even a weekend warrior wrencher. But any shop can do it, just get the $60 part and ask them to install, would be easy money for them.

[celsdogg]

OK. I took my E30 for a joyride yesterday and drove my F chassis to work today. Whole time i couldn't get your thread out of my head.

Just to check, your old slave cylinder was 21526795713? The diameters on realoem are exactly the same, just want to be sure! Also, the hard line you just replaced because of your leak, otherwise, we probably wont need it? At $60, i am guessing you got the FTE.

[Tchao]

Originally Posted by celsdogg

Just to check, your old slave cylinder was 21526795713? The diameters on realoem are exactly the same, just want to be sure! Also, the hard line you just replaced because of your leak, otherwise, we probably wont need it? At $60, i am guessing you got the FTE.

Yup, all the F-series 6 cylinder slaves are the same "5713" if I remember correctly.

I just got the FTE, its a good brand. And correct, I suspected the line O-ring to be faulty so I just got a new line too, which is not needed in your guy's case.

[AndrewC1989]

Will this work on the OG M2?

[Poochie]

Hey,

I verified the F30 335i uses the same slave cylinder as the F87 M2.

Also, it's the same exact size and PSI as the E92 335i (No CDV)

So you good to go, just don't forget a review



.

[AndrewC1989]

Originally Posted by Poochie

Hey,

I verified the F30 335i uses the same slave cylinder as the F87 M2.

Also, it's the same exact size and PSI as the E92 335i (No CDV)

So you good to go, just don't forget a review

.

So literally just a pnp swap of OEM with 21526785964?

[Poochie]

Originally Posted by andrewc89

So literally just a pnp swap of OEM with 21526785964?

Yes, from what I see, that's the latest part number.

If you order it in person, just tell them you want that part or whatever supersedes it.

From what I understand, whatever part number you give them, they receive the most recent revision of that part, even if it's not the same number.

Same core product just new for whatever small reason, from price to distributer.

[AndrewC1989]

Originally Posted by Poochie

Yes, from what I see, that's the latest part number.

If you order it in person, just tell them you want that part or whatever supersedes it.

From what I understand, whatever part number you give them, they receive the most recent revision of that part, even if it's not the same number.

Same core product just new for whatever small reason, from price to distributer.

Thanks for the info, as always. Looks like Santa came through for me.

[MLJR235]

Just finished up this install using the exact instructions put forth by the OP. Doing the reverse bleed method is a must and fail-proof way to effectively bleed your clutch line 100%. YOu will need a syringe type device to do it but it is well worth it, TRUST ME! lol.

Results are just as advertised. Off the line starts are way more predictable and honestly, the clutch feels "correct" now. No more hit and miss engagement points which are more annoying than words can express. ANyway, this a must-do mod for anyone who has ever had second thoughts as to why they got the manual trans on their late series bimmer. Cheers OP you deserve it

[Littlebear]

Hello BMW Experts!

The Febi/Bilstien slave looks like it is plastic.
What brands are you all getting, and is it plastic?

Murf

[Tchao]

Originally Posted by Littlebear

Hello BMW Experts!

The Febi/Bilstien slave looks like it is plastic.
What brands are you all getting, and is it plastic?

Murf

All recent BMW Slaves are plastic now.