Too much power for current clutch

[EuroDat]

Just read through this thread and it seems like you might have more than one problem.

A slipping clutch can be caused by two things. 1. Incorrect adjustment or 2. Worn out pressure plate or clutch disc. Pressure plate diaphrams can crack (not often, but they do) which can give the clutch a light feel and it will slip.

Check your clutch fork. If you can move it forward and backward in the slave cylinder, then its not an adjustment problem causing the slipping.

The very early series I 240Z had the adjustable push rod and a spring to pull it back into the slave cylinder. Remove the spring and check free travel.

The later type is non adjustable. You should be able to push the rod/clutch fork into the slave cylinder about 10-15mm depending on clutch disc wear and correct collar/pressure plate combination.

If you have no free travel or the adjustable version slave cylinder piston seems to come out to far, check your pedal adjustment. It's important the clutch master cylinder returns all the way. Otherwise it will not expose the rear port and fluid can not return to the tank. Follow the FSM to adjust it.

If all this checks out and it still slips then you will need a new clutch.

Your second problem, grinding in reverse is mostly caused by poor adjustment.

1. Then you have way too much free travel, which in turn will not cause the clutch to slip.

Other things that can cause a sticking clutch are:

2. Air in the hydraulics. Try bleeding the clutch.

3. A dry binding pilot bearing or spigot bearing as it as sometimes called. It's in the back of the crank and people often forget to lube it when doing clutch work.

4. When you disengage the clutch the clutch disc moves away from the flywheel a fraction. It does this by sliding along the input shaft. If the input shaft is really dry it won't move and the disc will drag on the flywheel.

5. Incorrect pedal adjustment. See FSM for adjusting pedal.

The original clutch should handle your engine without slipping.

If you are worried about the collar and pressure plate combinations, you can order the kit with the collar. Not as common as they use to be. Back when the series I was still common the replacement pressure plates were for the latrr versionand needed the corresponding collar.

 

Edited October 7, 2016 by EuroDat

[CooperZ479]

8 hours ago, EuroDat said:

Just read through this thread and it seems like you might have more than one problem.

A slipping clutch can be caused by two things. 1. Incorrect adjustment or 2. Worn out pressure plate or clutch disc. Pressure plate diaphrams can crack (not often, but they do) which can give the clutch a light feel and it will slip.

Check your clutch fork. If you can move it forward and backward in the slave cylinder, then its not an adjustment problem causing the slipping.

The very early series I 240Z had the adjustable push rod and a spring to pull it back into the slave cylinder. Remove the spring and check free travel.

The later type is non adjustable. You should be able to push the rod/clutch fork into the slave cylinder about 10-15mm depending on clutch disc wear and correct collar/pressure plate combination.

If you have no free travel or the adjustable version slave cylinder piston seems to come out to far, check your pedal adjustment. It's important the clutch master cylinder returns all the way. Otherwise it will not expose the rear port and fluid can not return to the tank. Follow the FSM to adjust it.

If all this checks out and it still slips then you will need a new clutch.

Your second problem, grinding in reverse is mostly caused by poor adjustment.

1. Then you have way too much free travel, which in turn will not cause the clutch to slip.

Other things that can cause a sticking clutch are:

2. Air in the hydraulics. Try bleeding the clutch.

3. A dry binding pilot bearing or spigot bearing as it as sometimes called. It's in the back of the crank and people often forget to lube it when doing clutch work.

4. When you disengage the clutch the clutch disc moves away from the flywheel a fraction. It does this by sliding along the input shaft. If the input shaft is really dry it won't move and the disc will drag on the flywheel.

5. Incorrect pedal adjustment. See FSM for adjusting pedal.

The original clutch should handle your engine without slipping.

If you are worried about the collar and pressure plate combinations, you can order the kit with the collar. Not as common as they use to be. Back when the series I was still common the replacement pressure plates were for the latrr versionand needed the corresponding collar.

 

Thanks for the information, I really appreciate it. I will see what I can find out after thoroughly looking through the FSM I just got on PDF. If you had to recommend new slaves/masters, and clutch kit, which would you go with? I have heard good and bad things about centerforce. Should I go ahead and get a new flywheel or see if it can be resurfaced? Also, which collar would fit the kit you recommend?

[EuroDat]

I just ordered a set including the hose from RockAuto. That was 5 years ago and never had any problems with them. I strongly recommend dismantling both and cleaning them before using, even if new. Mine still had machining grit inside which would have damaged the rubbers and reduced the service life.

My clutch is a new standard 280Z 2+2 clutch with a lightened flywheel. It works great and designed for the heavier 2+2and Turbo 280ZX. I like it because it has the light feel and still really good grip behind an L28 in a standard 280Z. You will need the 9 bolt 240mm flywheel. The 225mm has 6 bolts. A lot of aftermarket flywheels are setup for both.

I had the flywheel lightened myself from a drawing which I can post if you want. I think the drawing was posted by @Blue and I downloaded it. The machine shop changed a couple of radius' because they would make it (what we thought would be) too thin in places.

The main reason for me lightening the flywheel was to compensate for the heavier pressure plate. Its about 2,5lbs heavier and the disc is also a fraction heavier. The lightened flywheel makes it snappy of the line and help it accelerate better. My wife had a little trouble with stalling it the first time she drove it, but only in the begin.

Setup:

Flywheel: 240mm out of 280ZX 2+2 lightened to about 15lbs if I recall correctly. (Can check when I get back home)

Pressure plate: Standard unit via the Nissan dealer here in NL.

Clutch disc: Standard unit from Nissan.

Throw out bearing collar: My original 280Z collar.

New (Rock Auto) I think Beck/Arnley brand Master cylinder

New  (Rock Auto) Slave cylinder and haydraulic hose. Self adjusting type, (no adjustable push rod).

Ofcourse you can source others brands that are just as good. My experience up to now is positive.

[siteunseen]

I used an Exedy clutch kit and Beck Arnley slave cylinder and hose on both my 280 and 240 with a five speed swap.  I can't figure out why a kit for a 280 won't work on a 240?  What's different about them besides the shorter collar which isn't part of the kit?

Here's the one I have in both cars and so far they are working fantastic.

https://www.amazon.com/EXEDY-06009-OEM-Replacement-Clutch/dp/B001B5D7TE

[S30Driver]

As long as everything is matched, like Chas did with the turbo clutch & flywheel in his 280, there should be no problem.  Stock 240 / 280 clutches are the same, the beefier turbo has the larger 240mm surface area and you need the bigger disc & pressure plate to utilize it.

[Patcon]

3 hours ago, EuroDat said:

I had the flywheel lightened myself from a drawing which I can post if you want. I think the drawing was posted by @Blue and I downloaded it. The machine shop changed a couple of radius' because they would make it (what we thought would be) too thin in places.

@Blue

[EuroDat]

Here is the sketch with the alterations we made and a couple of files showing the difference between 225mm and 240mm.

I have it in Acad at work somewhere and it drop about 2.8kg which comes out just over 6lbs.

The Fidanza Aluminium flywheel is 4.85kg (10.7lbs) Fidanza P/N: 143281 and fits all 240Z, 260Z 280Z & 280ZX. Thats like over 50% reduction in weight. I think for street use its a bit of overkill.

I have read about people having problems with the Fidanza flywheel midlle bolt not lining up on the 3 bolt sections, but never seen one to comfirm it.

I have seen one car with a Fidanza flywheel (it was a 280ZX) and it wasn't real easy to drive from a standing start. I can remember when we turned it off and the engine just stopped dead like it had a hydraulic lock or something. It didn't idle all that smooth either.

[wheee!]

Great thread info!

[EuroDat]

7 hours ago, siteunseen said:

I used an Exedy clutch kit and Beck Arnley slave cylinder and hose on both my 280 and 240 with a five speed swap.  I can't figure out why a kit for a 280 won't work on a 240?  What's different about them besides the shorter collar which isn't part of the kit?

Here's the one I have in both cars and so far they are working fantastic.

https://www.amazon.com/EXEDY-06009-OEM-Replacement-Clutch/dp/B001B5D7TE

Hi Cliff,

 

It might be because the 240Z has a different pressureplate height than the later 280Z and 280ZX. A lot of people just simply buy the 280ZX with the collar and be done with it. I think that will be eventually the only option available, due the demand reasons. There is just a lot more 280Z and 280ZX's out there.

Your 240Z might already have had a replacement 280Z pressure plate when you changed it. If its still original, then you only need the collar from a 280Z or ZX and it will work perfectly.

The sketch and photo might help clear it up a bit. Im not ure if the sketch is 100% correct. I only know the 280Z, 280ZX non-turbo and the 2+2 & Turbo is correct because I have both in the garage somewhere. Btw, The photo is not mine, I think I found it here. Someone here might be the owner, so thanks

 

 

Edited October 8, 2016 by EuroDat

[Zed Head]

Here's a couple of old, somewhat rambling, threads about fitting the clutch parts together.

http://www.classiczcars.com/forums/topic/53029-could-it-be-a-slipping-clutch/

http://www.classiczcars.com/forums/topic/47034-please-help-id-my-transmission-year-clutch-replacement-gone-sideways/

 

[siteunseen]

Thanks Chas!  I see now why the 240 assembly kit is much more expensive than the 280. There's a lot more material on the 240s.  

The 240s 4 speed is shorter so I guess that's why the heights are different. 

Learn something every time I use this forum. 

[Diseazd]

1 hour ago, siteunseen said:

Thanks Chas!  I see now why the 240 assembly kit is much more expensive than the 280. There's a lot more material on the 240s.  

The 240s 4 speed is shorter so I guess that's why the heights are different. 

Learn something every time I use this forum. 

Not true.....The 240Z 4 speed (early and late) trannies,  the 280 and 280ZX  4 speed and 5 speed trannies......all are exactly the same dimensions. You can use either the 240Z clutch or 280Z in any of them. The important thing to remember is if you use a 240 Z clutch, use a 240Z collar and if you use the 280Z clutch use the 280Z collar. This is because the 280 pressure plate is narrower than the 240. I use the 240 Z clutch arm (with the hole) with the 240Z clutch and the 280Z clutch arm (for the self adjusting slave cylinder) with the 280Z clutch, but that's probably not necessary.......you can probably use the self adjusting slave cylinder and arm with either clutch....just not sure. All of my 5 Z's are F54 blocks and some 240Z trannies and some 280ZX trannies, but all use 240 Z clutches, 240 Z collars, early arms and adjustable slave cylinders......