Mcleod Rst clutch slipping

Discopotatoes · Post by **Discopotatoes** » Wed Sep 04, 2013 4:37 pm

I've got a mcleod Rst clutch and matching flywheel which is supposed to handle upto 800 hp,
In 4th or 5th when the boost hits about .8 of a bar the clutch begins to slip, its not done many miles and I've not abused it properly yet so I'm unsure how this could be?
Is there anything I can adjust or is it a whole new clutch?
The car is a rover v8 based tvr with twin turbos, I'm not sure of the power out put but its no where near 800 hp

DEVONMAN · Post by **DEVONMAN** » Wed Sep 04, 2013 5:10 pm

As you have said, the Rst should handle anything a Rover can chuck at it.

Have you checked the free play on the release bearing?

Discopotatoes · Post by **Discopotatoes** » Wed Sep 04, 2013 5:19 pm

Not as yet but I've just got off the phone to Mcleod who recon it's not run in yet, and if its slipping I need to check it for glazing and resurface it

DEVONMAN · Post by **DEVONMAN** » Wed Sep 04, 2013 6:34 pm

Unless you have thrashed it I don't accept the response from Mcleod. The clutch has 4 friction surfaces that would all need to slip.

As well as checking the release bearing free play also check that the master cylinder push rod is not loaded when the pedal is fully released.
(I assume it's hydraulic operated)

Are you using a Mcleod concentric slave cylinder?
What bellhousing are you using?

Discopotatoes · Post by **Discopotatoes** » Wed Sep 04, 2013 7:09 pm

DEVONMAN wrote:Unless you have thrashed it I don't accept the response from Mcleod. The clutch has 4 friction surfaces that would all need to slip.

As well as checking the release bearing free play also check that the master cylinder push rod is not loaded when the pedal is fully released.
(I assume it's hydraulic operated)

Are you using a Mcleod concentric slave cylinder?
What bellhousing are you using?

These are things I do plan on checking next week,
its the hydraulic slave on the t5 gearbox and belhousing not the mcleod one

DEVONMAN · Post by **DEVONMAN** » Wed Sep 04, 2013 7:50 pm

The twin plate Mcleod clutch is thicker than the original single clutch so if there is no free clearance at the release bearing you may need to adjust the length of the slave cylinder push rod or release arm pivot ball height or even trim the rear of the release bearing carrier.

I run a single 10.5" Mcleod clutch behind a 5.0 twin turbo Rover and have had no slipping problems so my guess is that your clutch diaphragm is constantly under slight pressure from the release bearing.

Discopotatoes · Post by **Discopotatoes** » Wed Sep 04, 2013 7:55 pm

DEVONMAN wrote:The twin plate Mcleod clutch is thicker than the original single clutch so if there is no free clearance at the release bearing you may need to adjust the length of the slave cylinder push rod or release arm pivot ball height or even trim the rear of the release bearing carrier.

I run a single 10.5" Mcleod clutch behind a 5.0 twin turbo Rover and have had no slipping problems so my guess is that your clutch diaphragm is constantly under slight pressure from the release bearing.

Cheers!
That's what I'm hoping for,
something that comes to mind is when it was first fitted I got a slight chatter from what I thought was the release bearing, i had to pull the clutch to change the spigot and it doesn't do it now, so maybe its gone back slightly wrong ?

stevieturbo · Post by **stevieturbo** » Thu Sep 05, 2013 8:57 am

Try and push the arm/slave rod back into the slave. There should be some free play here. If there isnt, the release bearing is maybe always pressed against the fingers partially releasing it

Blown v8 · Post by **Blown v8** » Thu Sep 05, 2013 9:45 am

What I did on mine,I cut the push rod down, then I found I cut too much off of it !
Used another pushrod,and then spaced the slave cylinder away from the bell housing,IIRC about 4mm

Discopotatoes · Post by **Discopotatoes** » Thu Sep 05, 2013 8:07 pm

Had a quick look today, and found where the slave used to have a couple of washer to space it out, they didn't get put back on after the new dust sheild was fitted, so I think that's my problem right there.

DEVONMAN · Post by **DEVONMAN** » Thu Sep 05, 2013 9:09 pm

Discopotatoes wrote:Had a quick look today, and found where the slave used to have a couple of washer to space it out, they didn't get put back on after the new dust sheild was fitted, so I think that's my problem right there.

If a couple of spacer washers have solved the problem you may need to space the slave cylinder a bit more when the clutch wears a little.

JP. · Post by **JP.** » Sat Sep 07, 2013 3:39 pm

When I got my Mc Leod clutch from Real Steel they hammered it in to run in the clutch properly before I wanted to abuse it. ever since its running fine.
So I took it on a spin to the UK, 700mile and run it without issues on Santapod.

Break/run in of a clutch is mandatory on any new clutch pack.

Post by **Coops** » Wed Sep 11, 2013 7:20 pm

DEVONMAN wrote:The twin plate Mcleod clutch is thicker than the original single clutch so if there is no free clearance at the release bearing you may need to adjust the length of the slave cylinder push rod or release arm pivot ball height or even trim the rear of the release bearing carrier.

I run a single 10.5" Mcleod clutch behind a 5.0 twin turbo Rover and have had no slipping problems so my guess is that your clutch diaphragm is constantly under slight pressure from the release bearing.

what gearbox you using mate?
as im in the hunt for a new clutch and im running the r380 (lt77 bellhousing)

DEVONMAN · Post by **DEVONMAN** » Wed Sep 11, 2013 8:21 pm

Coops wrote:
DEVONMAN wrote:The twin plate Mcleod clutch is thicker than the original single clutch so if there is no free clearance at the release bearing you may need to adjust the length of the slave cylinder push rod or release arm pivot ball height or even trim the rear of the release bearing carrier.

I run a single 10.5" Mcleod clutch behind a 5.0 twin turbo Rover and have had no slipping problems so my guess is that your clutch diaphragm is constantly under slight pressure from the release bearing.
what gearbox you using mate?
as im in the hunt for a new clutch and im running the r380 (lt77 bellhousing)

The single 10.5" Mcleod clutch from Real Steel will fit in a LT77 bellhousing but is a pain as you either need to redrill your flywheel or buy their steel flywheel. The hydraulic slave cylinder, release arm and thrust bearing all need to be in tip top condition or the clutch may not fully clear.

The plate splines is 1" x 25 so is that the same as a r380 shaft?
The friction surface on the Mcleod plate is very grabby and smells of rubber when you work it hard.

I have recently upgrade to a T56 gearbox and at the same time fitted a stronger Mcleod clutch cover, Chevy 2700lb instead of the 2400lb which Real Steel sell for the Rover. All the same bolt pattern.

Discopotatoes · Post by **Discopotatoes** » Tue Nov 26, 2013 2:38 pm

I've just got round to spending some time on the car, the clutch is goosed but I can't see how this could happen?

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The last photo shows the inner flywheel badly warped.