Need clutch help please

[Power Surge]

Ok, here's the deal... Drove the car around all day yesterday, performed flawless. As I was heading back to the shop to put the car away, I noticed all of a sudden that the pedal had some "play" in it, where there was no resistance for about the first 2 inches of travel. Once I got back to the shop, I couldn't put the trans in gear with the car running. Obviously, there was no longer enough throw to fully disengage it.

I checked the car this morning for leaks on the slave setup and found none. The clutch fork isn't loose either. Just seems as if all off a sudden I lost part of my slave cylinder throw.

Attached is a pic of the bar in the footbox. I didn't build the car, so I don't even know if it's setup right. But I do know it worked, and now something changed.

Any ideas on what it could be, or what I can check? Should I bleed the system out, and if so, what's the proper procedure for that?

[xlr8or]

If you just lost travel try bleeding the master and slave as you would your brakes.

[undy]

It sure sounds like and air bubble worked itself free..

[TRIG]

Same thing happend to me. I just bled the slave and it worked perfectly.

Trig2275

[Clois Harlan]

Bleed your master cylinder first (have someone pump the clutch a couple times and hold it down while you crack the bleed screw. Then do the same on the slave cylinder. I think you probably have air in your lines. Also, before you start check all your connections to make sure they are all tight and that none of your braided lines have been nicked by a rock or something from the road.

Good luck.


Clois

[Power Surge]

I don't think my master has a bleed screw, but I'll check. Worst case I can bleed by cracking the line to it. But I just vacuum bled all new fluid through the system and it seems the same. Still has the initial play before getting hard, and therefore doesn't have enough throw. What was interesting, is that the fluid that came out had the consistancy of dirty water.

[undy]

Seal, bore or internal M/C check valve failure??

[Power Surge]

Originally Posted by undy

Seal, bore or internal M/C check valve failure??

That's what I am thinking right now. The master moves a good 1.5-2 inches but the slave only moves like a half inch.

[Power Surge]

Ok, I'm pretty certain it's the master. I tried to bleed it out with no change. I think the first part of the bore is probably pitted up and bypassing fluid or something like that.

Does anyone know where to get one of these things? It's an AFCO part, and it's 3/4 bore. Other than that, that's all I know.

[kris-kincaid]

I called Afco last week about master cylinders and they no longer make the kind like you have on your car. Wilwood makes one that'll work.

[Power Surge]

Originally Posted by kris-kincaid

I called Afco last week about master cylinders and they no longer make the kind like you have on your car. Wilwood makes one that'll work.

This the one Kris?....

http://www.wilwood.com/Products/006-...RRMC/index.asp

[lineslinger]

This probably isn't the answer you want to hear but unless you can see and feel the inside of both the slave and master cylinder it is going to be tough to tell which one, if not both, are causing the problem.
I had the same problem on an austin healy, after putting new seals in both the slave and master clylinder I still had a spongy clutch that kept getting worse.
I ended up sleeving both the slave and master cylinder after finding some very light scoring on the sleeve walls of both cylinders.
Never had a problem again after that.
My point is if I would have rebuilt both of them the first time I would have saved myself a lot of time and "creative language" in the long run.
Good luck

[Power Surge]

Well, the slave is definitely bad. Pulled the boot and fluid poured out. But I found a source for the AFCO masters, so I have one of each coming and will just change both. Cheap insurance.

[undy]

It sounds like Mr. Hygroscopic was not your friend Sal...

[Power Surge]

Looks like I'm not out of the water yet....

Pulled the slave apart yesterday, and sure enough, the seal was split in half. The bore was pretty corroded up too. Picked up a new one this morning and put it in. Bled the system out, and it's exactly the same, just with no leaks. So looks like the master is bad too. Might have got hyperextended or something when the slave seal split.

So yesterday when I thought the master was bad, I called Billy at HRE to see where to get a new one. He said I any speed shop will have one, I just need a 3/4 bore Afco torpedo. So I call Afco to see if I can get it direct, or get a close distributor. The guy there says "call Capitol Speed in MA, they stock them". Ok, great. I give them a call, and tell them I need a 3/4 bore Afco torpedo master. After the slave didn't solve the problem, I go get the box from Capitol speed which had just arrived from UPS. Open it up... it's a 7/8 bore standard style with built in resiviour. Wonderful. Call up the Capitol Speed and I'm told they never stocked or sold the 3/4 torpedo.

So now I am back to needing a master. At least I know the slave is new now, and the old slave WAS bad. But I still am not getting enough throw action to release the clutch. I adjusted the slave to fork rod to preload the fork a little to move me closer to the release point, but that's not healthy for the car, so it's just so I can still move it around.

Guess I'll have to get the Wilwood version? Also, could I go up to a 7/8 bore, or should I stick with the 3/4?

[undy]

The 7/8" piston M/C will give you a slightly longer stroke on your clutch actuating rod at the expense of a slight increase in required pedal effort. I run a 1" cylinder on my master cylinder. Personally I'd rather have a longer stroke and give up a little more pedal effort as a trade off. You'll be fine with the 7/8" M/C..

BTW... If you can hang with a 03/04 OEM Cobra clutch then nothing a hydraulic Cobra clutch can muster will slow ya down...

Dave

[Excaliber]

My slave went out, I bought a new one exact replacement, piece of cake right?

While bleeding the brand new slave I over tightened the air bleed screw and ruined the 'seat'. Fluid shot out all around the bleeder valve. Go gently on those tiny little bleeder valves, new or old!

[Haz331]

You might want to look at Wilwood #260-6089 M/C .75 in. with 1.4" of travel. I used this setup with my push slave with no problems.

[WKB]

I am having trouble with the stroke of my clutch and while searching the forum I found this thread. I know how to fix the problem, but I am having trouble finding a suitable master cylinder. The one that I have is 5/8" remote reservoir girling P5060, but I need to replace it with a 3/4" bore like a Wilwood #260-6089. The problem I have is that the distance between the brake power booster and the clutch master cylinder is about the thickness of a piece of paper. This means I need a master cylinder that has an outer diameter of the main body of 1 1/16"(27mm). The PBR master cylinders that are available in Australia and which are similar to the Wilwood have an outer dia of 1 1/8" which is to big.
If someone who uses the Wilwood #260-6089 could tell me the outer diameter of the main body please or does anyone know another brand of a remote reservoir 3/4" master cylinder that would fit.
If all else fails I can use the larger diameter master cylinder and space it out, but that makes the pushrod longer which could be another potential problem.

Thanks
Warren

[Cobra #3170]

I just checked my AP's and they are also 1.20 but are much shorter than Girlings if that helps.