Source of clutch drag

[mattrosersv]

Any thought/ suggestions on this…?

I have a Mcloed RST twin plate and I have apparent clutch drag making gear changes problematic into all gears. It did not always do this but has been like this for past 5 years( not used car much).

The clutch mechanism is fine and disengages the clutch plates within spec.

Just pulled the box and there is play and noise in the release bearing, but it spins free.

There is a bit of oil about the place from a failed rocker gasket but I would expect that to make clutch slip not drag?

I will replace release bearing and spigot bearing and hope for best. Only other thought is flywheel damaged /corroded.

Will take clutch out once rugby is finished..

[colin_p]

My punt...

Weak or wrong diaphragm.

Did the clutch disc come with a revised diaphragm, or did you use what was fitted previously?

[mattrosersv]

It’s a twin plate clutch to handle turbo. Required the use of a chevy flywheel.

All looks like it was installed correctly.

There is blueing on the flywheel and floater plate. Could this be my issue? Still there is .025” clearance between each disc with clutch depressed so not sure that the blueing would drag the clutch.

Cheers.

[Zener]

You need to check for clutch disc's run-out (buckled/warped) too because your disc clearance will fluctuate/differ if so causing clutch drag/hanging-up , also check the hydraulics are doing their thing push-rod stroke healthy sound fluid etc , and plates move freely on input shaft spines

Edited by Zener on Sunday 20th November 16:30

[mattrosersv]

Thanks for the comments. All the basics checked hydraulics are all good and gaps checked with clutch depressed. Fork is fine etc Interesting comment on run out… not sure I have the means to check that.

I expect I will end up replacing the clutch in full. Will all Mcloed tech support tomorrow. Will post some pics when in front of my pc tonight.

[mattrosersv]

Pulled the pilot bearing and it is tight when fully engaged on input shaft. Reckon that could be my issue..

[Zener]

mattrosersv said:

Pulled the pilot bearing and it is tight when fully engaged on input shaft. Reckon that could be my issue..

Certainly could be whats the finish like on the input shaft nose? any damage or surface imperfections may gall the pilot bearing not ideal

[mattrosersv]

Looks Ok. It is like there is a shoulder on the bearing such that it slips on fine one way round but nips up when pushed up the shaft but is very tight from the get go when pushed on the other way around.

I’ll get a new bearing and see what that is like.

[hoofa]

mattrosersv said:

Pulled the pilot bearing and it is tight when fully engaged on input shaft. Reckon that could be my issue..

You mean clutch release bearing ? I too have the rst clutch ,and get a bearing noise on start up which disappears when warm, no dragging. Keep us posted what you find please

[mattrosersv]

The pilot bearing/spigot bearing is in the end of the crank. Basically a brass cylinder with a hole in it.

My release bearing spins free but there is movement in it and it is a little noisy when you spin it.

I have ordered up the bits. So will report back.

hoofa.. out of interest do you know if your release bearing carrier was machined down. I seem to remember taking 10mm off mine due to the added depth of the RST clutch..

[hoofa]

Yes the bearing carrier is machined down , is suspect I may have to take a fraction more off, I intend to replace the release bearing

[LongBaz]

I also have an RST with the same problem to the point where I now thinking of ditching it.
I have been looking at auto box, the one that I think may fit is a Power glide it is tiny.

[hoofa]

I think trying to understand the isssue would be beneficial, I had a single plate helix that was just awful in traffic, I need a twin plate for the clutch to handle the torques. I my clutch release makes the noise and disappears very quickly , I don’t get any clutch drag or have any issues selecting gear.

[mattrosersv]

If it is a noise I’d suspect clutch release bearing. Although I seem to recall from many years ago the spigot can make a squealing type noise.
Not too bad to do clutch release bearing. think it can probably be done by just removing gearbox (leaving bell housing in place).

My bits arrive today so will throw it back together and see what happens…

[Steve_D]

mattrosersv said:

Looks Ok. It is like there is a shoulder on the bearing such that it slips on fine one way round but nips up when pushed up the shaft but is very tight from the get go when pushed on the other way around.

I’ll get a new bearing and see what that is like.

Just spotted this.
Your description ties in with what I have seen before and that is that there is very little engagement depth of the spigot into the bearing. The result would be the bearing worn and loose where the spigot engages but tight further into the bearing.

Steve

[mattrosersv]

Got replacement bits. The spigot bush slides on spigot very easily. Could almost say there is a bit of play. Looser than the old one at its widest side and does not nip up when slid on. (I measured the spigot btw and it is the same across its length.
Might not get a chance to put back together this weekend so may be a week or 2 b4 I report back…..

[mattrosersv]

The Macloed is a twin plate with a floater ring between plates.

The instructions clearly state theat when the floater ring is fitted on top of the bottom plate (flywheel side) the plate should spin freely with no drag. Having fitted it today this is clearly not the case and while it moves there is definite drag,

I reckon that this is the problem. I'll call Mcloed tomorrow for advice, but this could well be the issue. I do wonder if a washer/spacer would sort it..

I'll update when this is sorted.

[mattrosersv]

Sorry, been a bit slow.

I finally chucked it all back together with a new spigot bush and also added 20 thou washers/spacers to allow the inner plate to float without drag.

Only ran it up in the garage so far, but it slips into each gear like a slippery eel.

So perhaps I have fixed it. I reckon it is the springs in the floater plate deflecting over time that are the issue and the 20 thou spacers make up for this.

Will get it out for a run tomorrow to check I have no clutch slip...