realcanuk

It is not required to change the slave, just probably a good idea to do it while you are in there. Mcleod suggests the RXT works best with a stock slave.

I sent you and email with measurements. Keep us posted please.

jon6.0

My RXT is going in today. McLeod steel flywheel.

Devilish34

didnt have any issues like this on my car or my friends C5..

briancb1

Man! Add me to the list, I'm having the EXACT SAME PROBLEM AS YOU!

I have about ~1500-1800 mostly freeway miles and my slave failed too with my RXT setup. Im pretty sure my shop just installed it and didn't take measurements, I'll ask though.

I'll follow this thread as I need a fix too. I don't have the equipment or area to work on a car right now so replacing these things are expensive.

Keep us posted please!

jon6.0

I'll remind my shop to check the measurement today.

realcanuk

I took all the measurements and sent them to the op. We should hear back soon if he found anything off.

turbotuner20v

Thanks again for that information Very valuable

So here are some numbers to crunch...

Extension of crank shaft past engine block/bell housing flange:
McLeod - ~0.330"
other shop - ~0.304"

Flywheel thickness:
McLeod - ~0.813"
other shop - ~0.820"

Clutch stack height:
McLeod - ~2.100"
other shop - ~2.750" (possible discrepancy on measuring range here)

Bell housing height:
QuickTime - ~6.440"
other shop - ~6.550"

Compressed slave cylinder:
me - ~3.4375"
other shop - ~3.350"

Uncompressed slave cylinder:
me - ~4.4375"
other shop - ~4.445"

Measurement 'A' (pressure plate finger to bell housing flange):
me - ~3.1875"
other shop - ~3.280"

Measurement 'B' (compressed bearing face to torque tube flange):
me - ~3.25"
other shop - ~N/A (not collected, but probably the same since our bearings were about the same size... or perhaps this is their 3.35" value from above and there was a miscommunication)


So here's some math:

Crank extension + flywheel thickness + clutch stack height = distance pressure plate fingers protrude into the bell housing

.304 + .820 + 2.100 (using mcleod's number) = 3.224"

soo... now we take

bell housing height - 3.224" = distance between pressure plate fingers and bell housing flange (measurement A)

6.550 - 3.224 = 3.326"

Using these values in an 'add up the thickness' method, measurement 'A' would = 3.326"

The straight up measurement of 'A' that the shop took was = 3.280"

So adding up the peices (and using the Mcleod supplied clutch stack #) would lead us to believe measurement 'A' was actually .046" bigger than it really was. So from here I'll use both of them to compare.

There was no measurement 'B' unfortuantely, so I'll have to use my own measurement 'B'.

A - B = preload

3.326 - 3.25 = 0.076 of space (no preload) - 'add it up method'

3.280 - 3.25 = 0.030 of space (no preload) - 'actual'

Now if we assume that 3.35" measurement from the shop for the compressed slave cylinder was the installed measurement, we'd get these numbers:

3.326 - 3.35 = -0.024 (preload exists) - 'add it up method'

3.280 - 3.35 = -0.070 (preload exists) - 'actual'

Now if we assume that 3.35" measurement from the shop for the compressed slave cylinder was the bench measurement, this would add .0875" of gap to the 3.25" number I got.

So there would be a gap of .1635" ('add it up method') to .1175" ('actual')

realcanuk

Few questions Jeff.

the measurements you call Mcleod....is that what they gave you or taken from your car?

Do you have a quicktime bellhousing?. Could that difference be causing issues ?

realcanuk

Few questions Jeff.

the measurements you call Mcleod....is that what they gave you or taken from your car?

Do you have a quicktime bellhousing?. Could that difference be causing issues ?

realcanuk

No clue why that posted twice !!

turbotuner20v

cliff notes:

The other install had 0.0925" more gap than me between the pressure plate fingers and bell housing flange.

This would mean that I would have 0.03" of gap vs. my -0.0625" of preload.


They don't make standard flywheels in those thickness increments though, the smallest is .200" oversized, which I'm pretty sure I don't have after this info.

McLeod did send me a 'street twin' flywheel to try as a replacement though. I believe it's marginally thinner than the standard LS/RXT flywheel.

As soon as I get my lift installed at the new house, I'll take mine apart for measurements too.

turbotuner20v

Measurements marked 'mcleod' are what they gave me from their files.

I do not have a Quicktime housing. I just used the Quicktime bell housing measurement I found online since it's the only one I could find online and neither mcleod or myself had that measurement on file. It is interesting that the specs from quicktime indicate it is shorter... something to consider possibly for quick time bell housing users.

briancb1

Updates?

69ls6

I had to same problem.My stock flywheel is .800 and mcleods is 1" even.So stack height is .200 high and slipped my bran new clutch

turbotuner20v

not yet, sorry, been a crazy fall... not sure when I'm going to get the car apart.. still running into delays installing my lift at new house

realcanuk

If you want to have some fascinating conversation about your problems,you should contact Red Roberts. Talked to him for quite a while at Sema. He eats and breathes this stuff. He is coming out with a slave that will be adjustable by screwing the piston in or out.
Almost forgot..... He is the founder of Mcleod and designed the RXT himself. Very helpful guy who is happy to help and share knowledge.


Forgot I took this pic of his new offering.

double06

As the clutch wears, the fingers will grow outward making whatever ride on bearing problem you have worse. That is why they recommend as mentioned in the notes here .150 to .200 no load clearance to account for finger movement as the clutch ages.

Gabbiani

Mine so far seems to be fine. I didn't put a mic on mine but measured out somewhere around an 1/8th clearance.

McCleod flywheel and rxt. Stock slave.

Yasei

Hey, looking at this pic, I doesn't look like you have tilted the drivetrain yet? How much can you actually pull back the drivetrain like that? I need to change my clutch line so I was thinking if that's doable without completely dropping the drivetrain... Were you able to change the slave cylinder like that as well?

Gabbiani

^^ I had a leak on the fitting at the slave and was able to get to the slave without removing the rear end completely but everything was hanging and slid back. The input shaft was still at the pressure plate and could not remove the slave. I really don't think you could get the bell housing out.