Clutch slave cylinder failure

[bstandley1]

As I was driving home yesterday, the clutch slave cylinder gave out. Fortunately, I was able to make it home ... barely! I removed the old cylinder (brake fluid the color of tar!) and ordered a replacement from the local NAPA store. While waiting for the new part to arrive, I took the c clamp out of the old cylinder and removed the innards. It appears to be a really simple device; a metal piston covered with a neoprene seal. I asked the parts guy if I could get a rebuild kit for the cylinder and he told me that the parts weren't available. Any of you folks ever order a rebuild kit for a Wagner slave cylinder?

One other question: The hydraulic line from the clutch master cylinder exits upward above the top of the master cylinder so I'm thinking that a pressure bleeder will be required to finish the job. The local parts stores sell pressure bleeders ... but will they work on the Lucas master cylinders? Appreciate any assistance.

Bob

[pgermond]

Bob,

You don't need to pressure bleed the m/c for the clutch... just regular bleeding.

A question for you, if you don't mind... what is the NAPA part number you ordered for your replacement clutch m/c?

Thanks!!!

Phil

427 Roadster, #4279436
Southern Automotive FE
3:31 and Toploader

Roseville (N.Cal)

[bstandley1]

Phil,

The NAPA store messed up the pick up so I don't have it in my hands yet. I do remember the parts guy tellimg me that NAPA'a part number was the same as Raybestos without the letters .. so I believe the NAPA part number is 33721. I'll confirm tomorrow.

Also, since the outgoing hydraulic line is higher than the master cylinder, won't I need some pressure from above or sunction from below to draw the brake fluid through the system?

Bob

[pgermond]

Also, since the outgoing hydraulic line is higher than the master cylinder, won't I need some pressure from above or sunction from below to draw the brake fluid through the system?

No... I never have. I just use a brake bleeder kit (inexpensive). Attach the tubing and reservoir of the bleeder kit to the bleeder valve on the slave and keep it lower than the slave. If you are doing it by yourself, fill the m/c, pump the pedal a couple of times, then check to insure the m/c has sufficient fluid, and do it again. Crawl under the car and check for bubbles in the tubing (it’s clear, so you will know when it’s good. If you have help, it makes it easier) I've done it a bunch of times by myself and it ain't no big deal other than having to crawl all over the car ;)

I would appreciate that part # when you have it.

Thanks!!!


Phil

427 Roadster, #4279436
Southern Automotive FE
3:31 and Toploader

Roseville (N.Cal)

[Brent]

I would throw the stock style slave in the trash and get a good CNC slave cylinder. Billet aluminum and A LOT more efficient than the truck cylinders people are using.

Eric Miller and Master just changed to these and have had amazing results. Maybe they will chime in.



Brent
427 SC Chassis #4279401
Candy Apple Red/White
402 FE/Toploader/3.54

[pgermond]

I'd be interested in specs/part #'s and ordering information.

Phil

427 Roadster, #4279436
Southern Automotive FE
3:31 and Toploader

Roseville (N.Cal)

[rdorman]

Me too! I get tired of rebuilding the $hit wilwood slaves.
Rick

http://www.ohiocobraclub.com
http://www.londoncobrashow.com

[Master]

I stayed with the Wilwood M/C and changed to the CNC 7/8 slave Cyl. Made my own bracket and it improved my pedal travel 25% from the stock slave. I was ready to throw in the towel and go with a HTOB but all is good now. My bracket is simple 6"L x 2 x 2 Angle Iron. I cut a 45 degree section at one end for header clearance and used the same mount point as original. I will take pictures tonight


Scott
4279454
SA 428
3:54

[pgermond]

Master - do you have a part# and source (please) :)

Phil

427 Roadster, #4279436
Southern Automotive FE
3:31 and Toploader

Roseville (N.Cal)

[bstandley1]

Phil,

NAPA part number is 33721 (got the box in front of me)

Bob

[souzape]

Master- what's a "CNC" cylinder?? Can you be a little more specific? I know I'm flirting with this problem too.

Phil Souza

[Brent]

Here you go,

http://cncbrakes.com/cncbrakes.com-asp//index.asp

Have fun!




Brent
427 SC Chassis #4279401
Candy Apple Red/White
402 FE/Toploader/3.54

[pgermond]

Thanks Bob.

Thanks Brent (I'm assuming it is the Series 305 push style)

Phil

427 Roadster, #4279436
Southern Automotive FE
3:31 and Toploader

Roseville (N.Cal)

[clayfoushee]

Phil, that has to be it.

Thanks Brent.

Clay

'98 Unique #9299, 427FE side oiler (452.1-stroker), top-loader (close), 3.31 rear

Annapolis, MD

[spd4me]

I got rid of my Lockhead and replaced with Wilwood pull type which is similar to the CNC. I checked the travel on both and the Wilwood gives close to 1-1/4" travel.

[spd4me]

trying to attach a photo
http://www.uniquecobra.com/uploaded/spd4me/SlaveTop.jpg

[pgermond]

spd4me,

Any photos of the bracket and mounting?

Phil

427 Roadster, #4279436
Southern Automotive FE
3:31 and Toploader

Roseville (N.Cal)

[bstandley1]

Phil,

I followed your advice and bled the slave cylinder ... with a slight modification to your procedure. Instead of pumping the clutch, I attached a second three foot long clear line to the brake bleeder kit (marked "vacuum"), cracked open the bleeder valve and sucked on the hose until the brake fluid started flowing without any air bubbles, then closed the bleeder valve. At the same time, my neighbor was adding brake fluid to the reservoir with a recently purchased turkey baster. The good news was that I didn't inhale any brake fluid, removed all the air, and only had to add about four ounces of fluid during the process. Life is good!

Now that the car is drivable again, I'm shopping for some well needed insulation for both the slave cylinder and the brake lines, both of which run uncomfortably close to the headers. Thanks to all for your help.

Bob

[spd4me]

Phil
Here's afew pics. The bracket is made from 1/2" steel and welded to inside of frame. I have a pic somewhere of the bracket before installed. If I find, I'll post. The washers are used to shim to line up at a slight angle to clutch arm since it moves back at on an arc.
http://www.uniquecobra.com/uploaded/spd4me/SlaveBottom68.jpg
http://www.uniquecobra.com/uploaded/spd4me/SlaveSide71.jpg
http://www.uniquecobra.com/uploaded/spd4me/Bottom.jpg

[Jim Harding]

Very clean and sturdy install.... nice fabrication too.

Jim Harding
La Plata, Maryland

1982 #3004
http://www.capitalareacobraclub.com/albums/album26/1aLeftside.thumb.jpg

[pgermond]

Thanks guys - I've been out of town... had to get out of this heat, so we went to Lake Tahoe(Incline and South Shore) for a few days.

Bob (bstandley1) - glad the bleeding worked out, although the very last thing I want to do is suck on a line that has brake fluid headed my direction! [:o)] Cool-It makes a reflective insulated sleeve that I used to excess on any lines that even come close to the headers - you might give that a try.

Bob (spd4me) - thanks for the shots of the slave mounting. Looks like you did a great job, but I got my head/neck all twisted around trying to figure out which end is up (my problem). I'll study them some more.

Thanks again!!!

Phil

427 Roadster, #4279436
Southern Automotive FE
3:31 and Toploader

Roseville (N.Cal)

[gasman]

Bob, Brent posted great diagrams of re-routing the master cylinder lines through the footbox inside the car under the carpet. Keeps everything away from the header heat. He also listed every part you need to do it. Great modification! I can't remember the name of the thread, maybe he does....Brent?

Steve Foushee
Unique #4279389

[spd4me]

Phil, the top and bottom pics are the same (laying underneath car and looking straight up. If you look close at the end oposite the clutch arm, you can see where the bracket is welded to frame. Middle pic is from trans looking at side of slave.