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Slipping clutch


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This is because the release collar on the 280zx transmission is longer than the one needed for the L16 clutch. Your slave can only move 1.18" and is running out of travel. You need the L16 collar it's 38.5mm long, the zx one 52.5mm long. When the clutch is let all the way out the release bearing is still pushing on the pressure plate fingers.... and slipping.

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wow meaning 1st i need the right collar 2nd bring down the transmission 3rd change the wrong collar for the right one n put everything back together ? :confused:  :yawn:  :rofl:  :rofl:  :poop:  :poop:  :poop:  :poop:  :poop:  :poop:

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banzai510 my boy told me i could shorten the rod so it could work better i just go the one that goes on the 1983 280zx it looks like the rod is 20161119_085910_zpsax2zbnia.jpg[/url20161119_090005_zpsqxj629ec.jpg


Try it, it may work but the clutch arm will be too far to the rear inside the bell housing from where it should be operating. It's going to be closer to the cover plate inside. 

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wow meaning 1st i need the right collar 2nd bring down the transmission 3rd change the wrong collar for the right one n put everything back together ? :confused:  :yawn:  :rofl:  :rofl:  :poop:  :poop:  :poop:  :poop:  :poop:  :poop:


.... yes. It always goes faster the second time. In the future remember that the clutch release collar is intimately related and matched to the clutch, and NOT the transmission used. Change the transmission but keep your release collar with the clutch.

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omg this would be the 3rd time i would bring it down this sucks all because lack of knowledge but thanks to you guys i have a better understanding on what i did wrong 

and how to fix it i mean damn it its a lot of work but i will have my baby on the road asap  :crying:  :crying:  :crying: i will let you guys what happen the minute i get enough time to work on 

my truck 

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Let's get something straight here, the 200mm clutch cover is the shortest, so it needs the tallest throw out bearing collar, the 225mm clutch cover is a little taller, so it needs a slightly shorter throw out bearing collar, and the 240mm clutch cover is the tallest clutch cover of them all and needs the shortest collar, all of these collars move the clutch arm to the correct position which is very close to the clutch slave to use the clutch slave rod that came with the slave.

One can only use a shorter rod to a point, as if the rod is too short the slave piston will come out of the clutch slave when one presses on the clutch.

It sounds like this guy adjusted the clutch pedal rod in the cab to the point that it has no play anymore and now the clutch is being pressed on full time since he adjusted the clutch pedal rod, he needs to back the clutch pedal rod off so that it has play again, there are two places that there is supposed to be play, one is the clutch pedal in the cab, there should be about an inch of free play in that pedal, it should not be firm to the touch, the other place there should be play is at the clutch rod/slave, there should be around a 1/16th inch play there, you need to adjust everything back to where it was before you remove the transmission, then determine if you can use a slightly longer rod between the slave and the clutch arm, or if you need to drop the transmission, as I see no markings on the rear of the clutch arm hole showing the arm was hitting the back of the hole.

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ok wayne im here I've been writing this but im at work so please help me  what exactly do i need to do i had to get ride to work today n catch the bus tomorrow morning because i didn't get to work on my truck today is raining in san francisco no garage no work done on my truck lol

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do what Wayno said,

you might be able to get away with not dropping the trans.



ps that spring really isn't all that needed by the slave. the clutch fingers should be more than enough to push the clutch fork back


also bleed the clutch and mabe the slave goes in abit more before you make a cut on that slave rod if you have to shorten it

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oh my god im having the same problem i have a 1973 620 i replaced my 4 speed with a transmission from a 1983 280zx i put in a  73 original clutch kid but kept the old slave cylinder on

i didn't adjust anything or had to bleed the cylinder it was running good for about 4 days and then it started


i couldn't shift to first gear or any gear at all unless i turn my truck off shift to 1st and start the truck with my foot pushing the clutch in


then it got worse now i had to turn the truck off shift to 1st gear but when i would turn my truck on the truck would just take off running

even thought i had my foot pushed all the way down


i adjusted the rod thats inside the truck on the clutch pedal bringing the rod almost all the way out it worked for  a day 


but i notice the it would slip a little bit on 3rd and 4th gear just a bit was running nice tho


the next morning it went from running nice 40 minutes later started slipping on 3rd n 4th gear n within an hour the tuck wasn't going more then 15 per hour on any gear


i changed the slave cylinder readjusted the rod on the pedal but is still slips on 1st 2nd 3rd n 4th i don't know what else to do but is really getting the best of me i need help asap please answer back with any suggestions thanks 

This is your first post here in this thread, see where you said "i adjusted the rod thats inside the truck on the clutch pedal bringing the rod almost all the way out it worked for  a day",

You need to undo what you did when you made this rod adjustment, the clutch pedal needs to have some play in it, from the sounds of it, the pedal is now pressing on the clutch all the time even though your foot is not on it anymore because of your adjustment.

Are you still using the stock rod for the clutch slave, or did you make a longer one?

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ok guys  i did it thanks wayno im not gonna lie after 40 minutes of adjusting turning the truck on and off and checking and double checking driving the truck around the block and for a few blocks adjusting again n again n im not gonna lie i cursed out the guys that came up with the design datsun makers n there moms n my truck a few times lol  :rofl:

hahahaha i finally got it to where im somewhat happy with it only problem now is that while my foot is off the pedal i can here a somewhat of a noise sounds like the throwout bearing and when i put my foot on the pedal it stops making the noise :confused:  but is running like a champ again and i can get to work tonight  :thumbup:  thank you datzenmike thank banzai510(hainz)  i don't need to ask anyone for a ride today yes!!!


the picture is just to save a rookie like me the headache of looking for the right tools lol

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The noise is not the throw out bearing if it goes away when you step on the pedal.

How much play do you have between the clutch rod and the clutch arm now, push the rod all the way into the clutch slave till it bottoms out and then check how much play you have, if you have more than an 1/8th inch you need to make a longer rod, ideally you only want a 1/16th inch play with the rod bottomed out in the clutch slave.

I am asking about this because if there is a lot of play, then the little piston in the slave has to move out till it hits the arm, if it has to move out to far, then when you press on the clutch pedal, maybe one day the little piston will pop out of the slave altogether and then you will not have any clutch till you fix it.

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Wano's correct on that.





This pedal adjustment. Push down on the pedal with thumb pressure. It should move, but only 1/16" no more no less befor there is resistance. Just a little wiggle room.

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If the master is not adjusted properly, without any freeplay, you can do damage to the crank. Constant pressure on the back of the thrust bearing wipes the oil away and then starts wearing heavily. I've seen cranks with no thrust bearing left and a groove in the crank. That's why a proper clutch master/slave adjustment is crucial.


Also be ware that there can be a top out adjustment on the pedal. If this has ever been adjusted be sure to take that into account. This adjustment is used to adjust pedal heights. If you want all the pedals equal and level with each other, that's what you adjust.


Yes, 1/16th of an inch is acceptable at the master.

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  • 8 months later...

Thought I would post this about my original problem which I finally solved. I dealt with the slipping problem by bleeding off the pressure occasionally because I knew I was going to put all new running gear in my truck pretty soon. Well, this spring I put a totally rebuilt L20b and another 5 speed in my truck. Some of the things I replaced was another clutch master cylinder and a hydraulic rubber flex line to the new clutch slave cylinder. Since then there has been no problem with the clutch. So I checked out my old flex line and it would barely pass fluid through it! It had broken down on the inside and was quite restrictive. I think the problem was in the master cylinder and the flex line. My new clutch is a Exedy Stage 1 Sport clutch and be forewarned it is stout. I am not complaining, but it takes much more effort to push in. But it does NOT slip. I posted this because it seems some people never come back to post their solutions and it leaves other people wondering how the problem got solved.

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