Tboh

2002 Camaro SS never had an easy day in its 45,000 miles. I hammer it every time I drive it. Just sayin'.

Clutch felt squishy this week and finally failed. It was shifting fine but felt as if there was air in the slave. I've been bleeding it regularly to keep the fluid clear and air bubble free. With this failure it would not go into any gear while running, With the engine off it goes into gear like normal. The failure came on over a few minutes with the clutch to the floor. Put it in and could not shift gears 1 to Neutral.

There was a little dry fluid coming from the boot under the dash and down the firewall. The MC felt soft and hissed a bit as I recall so I was going to change it first.

This is what I pulled out. It is a McLeod 139301:
[IMG][/IMG]

Adjustable travel universal rod end. (Top shelf compared to the stock/OE nylon bushing):
[IMG][/IMG]

Here are the internals, all look as new:


This looks like a failed cup. There is a groove where it crossed over one of the two holes:


Update: This is smelling of a design flaw. The cup should not ride over the fluid inlet holes. It's a guaranteed failure point. ( Or not. Looks like a manufacturing issue and not design so much. I have de-burred the holes and will live with it. )

The part is a standard brake part for any 13/16" bore. Can be obtained anywhere in bulk or a pair from a wheel cylinder or Autozone Wheel Cylinder Repair Kit #66573.

I got a Cup from Autozone from a wheel cylinder 13/16" bore. The spring from the McLeod was weak looking and failed on rigorous inspection so I took the one out of a new stock MC.
[IMG][IMG][/IMG][/IMG]

I machined the small aluminum guide to match the one from the McLeod except for the through hole in the center.

I chamfered the hole edges to help that cup last longer. I still have my doubts about the design here. Those holes should be away from the seal travel.
[IMG][/IMG]

I reassembled and bench bled the MC. I have great pedal pressure after a good 10-20 cycles at bleeding the air out of the slave. Nothing but clear fluid from the bleed screw, no bubbles and it's hard to crack when the pedal is to the floor. (So there is pressure getting to the Slave from the Master) The MC is moving fluid great but I'm not too confident with it given my surgery on it.

Problem: The trans will not shift when running. Nothing. Shut it off and will slip into any gear.

Does this mean the clutch is stuck? Not actuating? How do I trouble shoot this to locate the fault?

I just rocked it a bit in 1st gear. The trans is engaged to the flywheel it seems. Could I have a broken trans or clutch resulting from a failed MC? Or could a failing slave kill the Master? There is no fluid under the trans.

Update:I just lengthened the travel on the rod to eliminate all the free play in the pedal. It always had a 2" slop that I just lived with. It grabbed hard mid travel so it was fine. Should be maximum travel on the MC now with a longer stroke. Took about one turn of the connector rod. Still nothing. Re-bled it and a few tiny air bubbles came out.

I'm surfing the great info on this forum and getting the feeling I have a bad throw out bearing. The way it failed was the clutch getting worse over minutes. Maybe the throwout bearing was seizing preventing the slave from moving the pressure plate? The MC has damage so maybe the back pressure was too much for the already worn cup. Hmmm.

Any thoughts on this? What slave to get to go with this McLeod Master? Or just do the Throwout bearing?
Thanks guys,
Tboh

Spartan7

iTrader: (7)

That looks like the old style McLeod MC. I had the same issue as you, torn cup seal. Mine was a defect in the bore that kept tearing the seal, even after a rebuild. Contact McLeod and see what they can do for you, they upgraded me to the newest Wilwood design free of charge. Here's my original thread.

https://ls1tech.com/forums/manual-tr...build-kit.html

Tboh

This makes sense as the two holes for fluid inlet are the same diameter of the damage on the cup.

I'll drop McLeod a line. Thanks for the advice.

BALLSS

McLeod stoped using Tilton MC. The 2 holes inside where the lip catches are not camfered so the cup tears. I saw another thread where a wheel cylinder kit from NAPA (assume most auto part stores) for a few $ would repair this but same thing later.

Now McLeod offers Wilwood MC's. They make the 'adapter" for vehicle specific and put on a adjustable threaded rod end

I have the McLeod MC (Wilwood) as part of my Twin disc clutch they sell. nice piece.

Tboh

Sounds liek you have a nice setup there. How streatable is the twin disk?

Is the MC I have a Tilton? Are the holes in the same place on the Wilwood MC and the one I have? That's the million dollar question. And is the cup supposed to rest behind one or both holes?

I could ramp the holes to keep the cup from scraping the hard edge. It can only help.

I cannot get the slave to engage with the OE MC. I'm pulling great amounts of fluid through with the MC and it's soft but fluid full, no air on bleeding.

I'm going to pull the OE MC, Refit the McLeod with a new 13/16" cup, chamfer the holes and replace the spring in the McLeod. Then bleed the thing well on the bench.

This is maddening.

BALLSS

My McLeod Street Twin is the best clutch I have ever had. smooth "stock like" engagement but when you dump the clutch there is no slip what so ever. The LS version you can get organic or ceramic puc type disc RST or RXT.

I have a LT1 so my hydraulics are diffrent than the LSx you have. The Wilwood I have does not look like the Tilton MC McLeod used to sell for the LT1 "pull" type clutch. I suspect yours is a Tilton as it looks like the LT1 style made bu Tilton but for the LS..
They use the compact Wilwood 13/16 MC and they make the adapter to mount it to the F-body and add the threaded rod. I assume it is the same MC as the LS but diffrent mounting bracket part. Check McLeod site, I suspect they have a pic/part # to see.

if you can get inside your MC and take the sharp edge off of th holes and just rebuild you may be good. Your problem was common on the LT1 Tilton MC's that McLeod used to offer. Maybe they changed over to Wilwood because of issues.

my McLeod MC

Spartan7

iTrader: (7)

That's pretty much why. They replaced my old Tilton one with the newer Wilwood piece free of charge because it was a known defect. I really like the newer style, very nice part. I have the same one as you.

BALLSS

yeah I know, PM you when I got mine about bleeding.

My set up uses F-body hydraulics but I have a fabricated pedal assembly in a B-body

for me, one thing that helped with the Mcleod unit is I could remove their mounting bracket and orientate it 180 so the fill fitting was then positioned in a way I could get to it once MC was installed in my pedal assembly

This is not a issue for you or the OP but made my deal a go vs no way deal. I dealt with the whole hydraulic install before putting in the twin as if it did not work I would have returned the twin and gone back to stock hydraulics and single disc clutch

Also wilwood is local to me and they were very helpfull on a few ?'s I had.

I feel this MC would benefit a single disc clutch because it comes with a unrestricted braided steel line to the slave. McLeod makes both 7/8" & 13/16" bore MC's but recommends the 13/16 for the 4th gen F-body and is mandatory for their twin.

On bleeding, got to do it on the bench, then connect slave.

Spartan7

iTrader: (7)

Oh yea, now I remember. Glad you got it figured out, it really is a nice MC.

Tboh

Hey. Related to that... Does the Slave have to be matched to the Master cylinder? Can I use a stock OE Delco Slave with a 13/16" Master? Or is there a better match. I think I have a McLeod Carbon fiber clutch in my LS1. Won't know until I get it apart.

PS. Sounds like you have a nice car there too...

Thanks.

BALLSS

Tboh, is your car LT1 or LSx?

I used a new OEM (bought at O'rielys) slave with my McLeod MC. My original was fine but I wanted to keep the original MC & slave intact.

The MC came with the fitting and roll pin to attach to my slave.

the fact 13/16 larger bore does not mean you need a diffrent slave.

if you have a LT1 pull clutch I would suggest when you first start the car with the McLeod MC don't have the clutch pedal pushed all the way down. You can extend the fork enough it will make contact with the PP and someone reported he striped his starter because the fork prevented the FW from turning because it was contacting PP when he initially had clutch pushed all the way in

On mine when I was pushing it in clutch would not completely disengage. I started adjusting the MC rod and got to a point where the fork just started to buz the PP but still would not disengage the Twin (twins need slightly more slave travel). I wound up shaving off .125 drom the base of "T" stud the fork rides on on the advice of McLeod and that resolved my issue. This only applies to LT1 Twin disc clutch, not a single disc.

McLeod may offer a slave also, check for your application.

Tboh

I have an LS1.

I'm thinking I have a bad slave or T/O Bearing.

I just ordered a new GM Slave, the TICK Speed Bleeder and got one of these:
[IMG][/IMG]

I read up on how to do the removal and full tear down if needed. I'm planning to change the slave and take a look at the McLeod clutch. I hope I can see the friction plate to get a measurement on the wear.

How do I know the spec or the health of the pressure plate?

BALLSS

you can't tell the condition of the disc or PP without removing them.

that harbor Freight tranny jack is a MUST to R&R tranny. Worth the $50 hands down

Tboh

Dang. Oh well. I'm going to put her 2' in the air and use the trans jack to fix this thing.

The jack looks like a well built tool. I bet I'll use it quite a bit.

Tboh

Ok. I got the slave out. What a tight fitting trans. I'm not looking forward to putting that top passenger side bolt back in.

The Slave is wet as is the whole area where it was bolted. It's a little grabby or rough when depressed by hand. Totally caked in clutch dust as if pushing fluid out the front seal. The TOB is not as smooth as the new one but turns ok, not grinding.

[IMG][/IMG]

There is a fire engine red pressure plate with good even looking fingers/tabs. Looks like the McLeod that Thunder Racing put in.

There is an aluminum disk behind the old Slave. Must be a spacer(?)

Now I have to put on the TICK Speed Bleeder and bench bleed this thing.

People do this for a living... tough stuff.

Tboh

RE: Bearing Clearance Spacing for the new Slave. I get 2.424" from the fingers to the flange. 2.150" from the TOB compressed to the trans flange. That gives a gap of 0.274". I have a steel spacer in there (0.231" laser cut). I'll add an 0.080" spacer to give me a gap of 0.194". [3/16 = 0.1875] so that's where I'm thinking I'm going to get the best wear and slave to plate movement. The clutch is already broke in but I'm having shifting issues so this should work.

Tboh

Ok. I've changed the Slave, rebuilt the Master, put in a 0.090" spacer, installed the TICK Speed Bleeder but I get the same problem persisting.

The car is on stands. The wheels spin when its put in first. It slips into gear as the wheels spool up. And they spin fast too. It seems the clutch is not disengaging.

I'm sure I've got it bled well. Could the clutch be simply broken or worn out? Any advice?
Thanks.

BALLSS

if the MC you rebuilt is still the tilton MC McLeod used to offer...that may still be your issue. Yeah the brake cyl rebuild part deal is what many did, even smoothing out the edge of the holes in MC bore. My guess is the MC is still allowing air in.

My hydraulics are LT1 so not the same as yours but still involve MC & slave.

'maybe", even with all your efforts to smooth the cyl bore where holes are, it still cuts the cup and the same deal.

If Mcleod won't warrenty a swap like Spartan than either buy their MC (Wilwood) or get a TICK

it is possible your PP puked (you would have to pull it out to inspect)) but I suspect the hydraulics are still your issue.

When I had my entire pedal/hydraulic assembly on the bemch (again not like your set-up. mine is a custom fabrication) after bleeding I could just "lay a finger" on the clutch pedal and see a immediate corresponding slight movement in slave so there was zero air in the system after I bench bleed both MC & slave seperate then pumped slave with everything assembled. Obviously if I pushed the pedal I would have puked the guts out of the slave this way without it being installed but it did signal immediate response in hydraulics. If you have it apart again with slave/TO bearing out just slightly tap clutch pedal and see if there movement immediate with the slight clutch pedal push

does the pedal feel stiff for the entire throw or is it "soft", especially up top?

Tboh

You might be right with your assessment that it goes back to the master. McLeod will not warranty the part, too old and it lasted 10 years so I don't take that as a negative. i believe their repair kit is no better than the repairs I made. The TIC MC is probably the way to go.

I have the pedal rock hard. It does feel a little softer when bleeding but only when the bleeder is open and I'm flushing. Its spring pressure from the one I replaced in the MC. It does firm up if I wait a few seconds as it takes a sec to fill the MC from the reservoir. There are no bubbles coming out so I can't see it having any air or a leak. Close the check valve and its hard pedal top to floor.

I guess the options are slim. New setup including MC or just add a new MC and see what happens.

Thanks for the advice. Appreciate it!

BALLSS

did you try and adjust MC rod to allow for more travel?

I am not familiar with the "shim"part but understand why on the LS cars. Is there a diffrent thickness (more) shim you could put in that would give the TO bearing more throw?

If your pedal is rock hard, sounds like your rebuild worked

I hear good reports on the TICK MC. The ones McLeod sells are Wilwood with the "adapter" part made by McLeod. It is also a very nice unit.