McLeod Throwout Bearing Failure

[lewma]

All

Went to take the coupe for a drive this morning. Clutch pedal soft all the way to the floor, master cylinder almost empty. From all that I'm reading, the throwout bearing has failed. Haven't torn the engine/trans apart but I'm expecting fluid all over the place. Glad it happened in my garage.

Anyone recommend a reliable hydraulic throwout bearing that works with:

- Tremec T56 Magnum
- McLeod RTX Twin Disc Clutch

This is my second mcleod bearing. First one failed before mile 1. Really not interested in a 3rd.

May even go back to old style clutch cable for reliability.


Any advice greatly appreciated!
mark

[Lidodrip]

Many have had good luck with Tilton, including myself.

James

[Jeff Kleiner]

And folks ask why I don't recommend hydraulic throw out bearings. Sorry about your luck (twice) Mark :(

Jeff

[edwardb]

X2 on Tilton. 10K miles on my Coupe with 6100-Series Tilton HRB and going strong. Have another installed in my Mk5 Roadster build. Bled and working. Waiting patiently for its time. Very high quality part with a great reputation.

Sadly, I've heard several reports like yours with McLeod.

[lewma]

Thanks for the responses everyone. Im thinking of going with the Tilton 6100

Mark

[Cobraman]

I use only a slave cylinder now ask me why :confused:

[JimStone]

Oh man, bad luck Mark.

At least it gives an opportunity to put that shifter shroud kit on? I'm sure you'd rather not

[lewma]

Jim, I ended up putting the tick performance shifter base on the transmission ( cut out the diagonal cross member too ) as I was a little uncomfortable placing the shroud inside the transmission incase those parts decided to work loose over time ( with my luck, they definitely would ).

Just ordered the tilton bearing. Hopefully I can separate the engine/trans while still in the frame and swap out the mcleod bearing. If not, the whole thing comes out :(

[flight_83]

External slave cylinder is my vote.

[JTG]

Sorry to hear about this Mark.

For anyone else that has experienced this failure, what exactly fails? Is it a bad seal, or just a generally bad design?
I already have a McLeod TOB and now feel slightly hesitant to install it.

[lewma]

Sorry to hear about this Mark.

For anyone else that has experienced this failure, what exactly fails? Is it a bad seal, or just a generally bad design?
I already have a McLeod TOB and now feel slightly hesitant to install it.

From what I'm reading, its usually the seal, but an incorrect pedal stop causing the bearing to over-extend also contributes to the problems. I thought I set my pedal travel correctly but I'll be checking that again when the Tilton is installed. My first one failed before I even had the car off the jacks. Should have raised the red flag right there but it was swapped out without question and I moved on.

I'm also swapping out the wilwood master cylinder for a tilton while I'm at it. Already did the brake master cylinders a few months back.

[Jeff Kleiner]

...Hopefully I can separate the engine/trans while still in the frame and swap out the mcleod bearing. If not, the whole thing comes out :(

Mark,
I can't speak for the T56 but from personal experience I can say that R&R of a TKO isn't too bad on a Gen3 (aside from that pesky gravity deal when lifting it back in ;)).

Good luck!

Jeff

[lewma]

Jeff

I did it before while building the car but I had a lot more top side access. Not so much now ;) Fingers crossed I can get to the bolts from the underside and persuade it to slide back enough. I think I can remove the trans tunnel top and get to some bolts too.

mark

[ggunter]

1200 miles on my McCloud HTB and fail, 17800 miles on a Tilton still works:cool:

[turbodon]

What clutch are you running?
If it is a super clamping force clutch like King Cobra etc. The internal slave will probably fail. I usually run a twin disk (Mcloud RST) with the internal. Higher grip with light clamping force.

[lewma]

What clutch are you running?

McLeod RTX Twin Disc Clutch

[lewma]

For your viewing pleasure ;) Only 6K miles :mad:

Tilton version is already in. Didn't need to remove the engine in the end. Managed to separate the T56 still in the frame and swap it out.
225791

[JTG]

Glad you got it fixed!

I'll probably go with the Tilton at this point so we don't have the same experience. Can you post up a link to the exact model you bought? We're also running a T56.

Thanks,
Jon

[lewma]

I'm using a Tilton 60-6105 that also comes with a Tilton 62-899 mount adapter. Make sure you verify your exact transmission, engine and clutch setup to make sure it's all compatible

[Sharris2]

Just curious do you have a clutch peddle stop? Very important with internal Hydraulic bearings.

Scott

[lewma]

Yes

[edwardb]

Both internal and external hydraulic clutch release systems can have major failures if over-driven. Tilton's instructions are excellent and make this point very clearly. But the same idea is true of all types and brands. For both my Coupe and now the Mk5, with Tilton HRB's, I didn't install clutch stops. Heresy you say? :rolleyes: In both cases, with the clutch pedal hard against the back wall of the footbox, I'm not exceeding the throw and the clutch is fully released. So a clutch stop wouldn't add anything. This is the result of using a 13/16" MC (Tilton recommendation) and where the Wilwood pedal is located. YMMV

[nick729]

Any tips on how to bleed the same Mcleod throw out bearing? Spent half the evening trying to bleed the damn thing, but no progress.

My throw-out bearing is not moving at all and it is not jammed (i tried prying it gently and it moves), and the system does not seem to build any pressure at all.

My bleeding procedure - clutch reservoir filled and with the cap off, i have a bottle with brake fluid and a hose from the bleeder nipple submerged in the brake fluid. Pump the pedal 15times, keep the pedal pressed and crack the bleeder valve, let the air out, close the valve and release the pedal. Rinse and repeat. I tried gravity bleeding for 30mins a few times just in case - no luck.

The supplied Wilwood master cylinder seems to be working ok, no bubbles are coming back to the reservoir when pumping the pedal. No leaks either.

228145

[lewma]

Nick
I did a reverse bleed when i replaced my bearing ( with a Tilton ). Get a syringe and push the fluid from the bleed line until you see fluid in the reservoir. Seemed to work very well.

mark

[F500guy]

I tried some bleeding like you would do for brakes and no worky. Had to do the procedure that they recommend in there information. It takes a big high-volume push to get it done. Looks easy with 2 people and a car lift, but 1 person, and car on jacks a real PITA. I did it twice and cleaned up after both!

[lewma]

reverse bleed worked very well. open the bleed line, push fluid, close the bleed line. repeat until you see fluid and no bubbles in the master cylinder. Did it by myself

[nick729]

Thanks for the input! I have in the meantime ordered a vacuum bleeder, should get it by the end of the day and see if that helps - https://www.amazon.co.uk/Kraftmann-18087-Brake-Bleeder-Pieces/dp/B075DMW95T

I can use it on the brakes too, since that also needs doing - if that fails, i will try the reverse bleed as suggested. Thanks @lewma

[turbodon]

I used a bit of air pressure on the master reservoir. Open bleed and let it start running out bleed.

[nick729]

So I am either doing something wrong or I don't know what the issue is...

Vacuum bleeder did not work
Gravity bleeding did not work
The standard pedal pumping and cracking open the bleeder did not work

As per suggestions i tried reverse bleeding. The issue with that is that even with the bleeder barely open like 1/8-1/6th of a turn it leaks through the part where the bleeder is screwed in (marked in the picture). Opening the bleeder more makes it worse, closing it more closes it completely. Also, when i try to reverse bleed it is very hard, like i need to push very hard to get even the tiniest of the fluid in - not sure if this is meant to be like that or not..
i managed to get about 30ml up into the reservoir before the syringe hose blew off and i drenched the entire car in brake fluid..
228596228597

I am seriously starting to question what is the issue...

The throw-out bearing does not move from this position (pic 2), regardless what you do with the brake pedal. I am beyond frustrated.

Any thoughts?

[F500guy]

I hear your frustration, that is an AN fitting, the seal is the face of the 2 parts, not around the hose so if the 2 parts are loose or that is an NPT fitting in there it will leak. Check out the video that they put out for bleeding, if all else fails and it sounds like that is the case, that hose end will need to be immersed in fluid when you pump the pedal, then the cap and the end has to be tightened while it is immersed in the liquid. Since you put teflon tape on the male threads, it appears that it is NPT type and not AN type.

[PMD24]

I think F500 has it right. You are pulling air in because there is no seal at the AN seat. Teflon tape on the threads is of no use. The threads are not a part of the seal. Immerse the fitting that comes out of the bearing into fluid while bleeding and everything will likely be ok.

If you want to make it longer with that piece of tube, use an AN to barb adapter, no tape.

Pat

[nick729]

Thanks, i will try the method of dipping the entire bleeder with the AN fitting into brake fluid and pumping the pedal to let the bubbles out and suck in the brake fluid that way.

Thank you!

[turbodon]

Nick729

Use a rag and a little air in the top of the master to create pressure with bleed open. When you get pure fluid stop. Do not push all the fluid out of the master stop and fill. I removed the rubber from under cap. put cap back on with rag around cap. Blew air puffs from compressor nozzle in hole in cap with a rubber tip on nozzle. It only takes a bit of air to build pressure.

Do you have play in the clutch pedal to master. Can you lift pedal up and down with a little play?