Does This Clutch Need To Be Replaced?

[Sm3g]

Hi clutch gurus!!

I was wondering if you could take a look at my clutch / flywheel / throw bearing and tell me if it requires replacing? The clutch plate looks like its still got a lot of meat left on it (I am no expert), and the flywheel seems pretty smooth although it does have some markings on it. The throw bearing its self was noisy before it removed the clutch, at one stage I couldn't even get it into gear unless the engine was off.

A little back ground info also; I have only had the car around 1200 km's and I am not sure when the clutch was replaced, the previous owner did say he changed it "recently". I have done one burn out in it (fairly decent one). The next time I tried to do one it wouldn't even spin the wheels. I am not sure if the throw bearing was noisy prior to these burn outs.

Is the clutch / flywheel salvageable and just change the throw bearing, or is she kaput and spend the cash now?

Youtube video of the throw bearing in action

Edited August 29, 2014 by Sm3g

[MrStabby]

Google for thickness specification of the clutch plate, check your plate thickness with callipers, keep using it if its within spec

[89CAL]

Yeah, email Exedy dealer would probably be the best way to find out the info you are after.

It looks nowhere near down to the rivets but, put it back in and go again

[boostn0199]

Looks like its got heaps left in it.

[Sm3g]

So any possible reasons for it to slip, not hold properly apart from the throw bearing?

[Duncan]

yep, clutches don't just slip because they are worn.

They also slip if they get too hot (probably what happened here) or if you have too much torque for the clamping pressure.

BTW if the thrust bearing was noisy change it while it's all apart. cheap and quick fix when it's opened up

[89CAL]

Also can happen if you have an oil or coolant leak in the rear section of the engine. That one is a bit more obvious though, you would probably see something if there was a leak, but if not check the welsch plugs at the back of the block for any signs of leaks

The flywheel doesnt look like its got terribly hot, but hard to say for sure from photos.

How much power does the car make? It looks like an Exedy HD clutch, which might not take an awful lot of power over stock.

When is the clutch slipping BTW?

[Sm3g]

There is a lot of black dust in the bell housing and on the clutch its self. The flywheel does look like its got a lot of heat marks on it, not so much on the GB side of the clutch but the engine side for sure. The last dyno was about 4 years ago and it said it was pulling 250 kW at wheels.

After the first burn out, I did a service on it (changed GB oil, Diff oil, engine oil/filter, yet to change fuel filter till i change my lines). After the service it wouldn't get back into gear while the engine was running, so I stressed for a couple of days researching and went back out and it started working again. I took it for a small lap around the block being uber cautious not reving high at all, so I'm not sure if it was slipping at high power out put whilst moving. Prior to the first burnout it was not slipping at all. After this I was about to take the clutch out and inspect so I decided to drop another burn out, this time it wouldn't grab at all (no wheel spin) on already baldish tyres.

[89CAL]

I think you need a clutch upgrade, sounds like too much power for an Exedy heavy duty, if thats even what it is

[Sm3g]

I have sent a message to exedy, hopfully they can give me some info. A search with the NSD140U part number doesn't give any specs on the clutch.

[Sm3g]

Well had two wins today...

Exedy got back to me with this;

The 25017 Pressure Plate is our Sports Cover Part No NC-11T

The Plate we use under this cover is a Sports Plate ND-20H

The Bearing is a pull Type Part No Brg-601

If you purchase a NSK-7172SO you would have all components listed above

The NSD-140U IS A 350Z Plate

The NSK-7172SO kit would cater for 275 Kw at the wheels

Not sure why a 350Z plate is on the skyline but any way I will stick with it for now, just got a bearing and alignment tool from http://www.cbaus.com.au for $75, they were the only ones to have the part on site and also the cheapest (Perth).

[Sm3g]

Good news!! Got the gear box back in with the new bearing and it works perfect!

I put the failure down to hardened grease on the input shaft of the gear box not letting the bearing slide back in swiftly.

I cleaned up the flywheel with dry scotch bright (green scour) to get rid of some heat spots and general muck off them. Also removed all dust and old caked grease off everything.

When I installed the clutch/box back in I didn't put any grease on anything.

The clutch grabs and releases like it should now, no slipping or noise.

It even looses some traction when dropping the clutch into 3rd, mind you the tyres are a tad worn (50%) and the surface was fairly smooth.

All in all glad I tried the bearing first and cleaned it up rather than spending 1-2k on a new clutch straight away.

Thanks for all the help to people, much appreciated!!!

[89CAL]

You should always put a bit of lube on the end of the input shaft where it goes into the spigot bearing. Peronally I like to use some anti sieze or such on the pivot ball so you dont get the sqeak from the gearbox on clutch in/out

[Sm3g]

When you say spigot bearing do you mean the splines of the input shaft into the clutch splines or the release bearing?

[iruvyouskyrine]

No he means the last part of the input shaft that tapers down to fit inside the brass bushing (spigot) that sits in the end of the crank and locates the gbox input shaft. In the picture it's the part of the shaft with the smallest diameter.

You also get bonus pictures of my old and new spigot.

[GeeDog]

^^That old bush looks like it put up a good fight:)

[Sm3g]

I see, it does look like it put up a good fight

So was that due to no grease/anti-sieze do you think?

[iruvyouskyrine]

No that was due to Nissan sending me the wrong spigot and my mechanical inexperience (first time installing one, had no idea what I was doing!) didn't realise it was incorrect size.

But still put anti-seize/engine oil/some form of lubricant on it and the gearbox input shaft before it all goes back together.

[Sm3g]

Ahhh ok, so was it to big or too small? Also what other damage did it cause, how did you notice?

Edited October 20, 2014 by Sm3g

[iruvyouskyrine]

It was too small inner diameter. No damage done and only noticed when I took my gearbox out.