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FS5R30A Transmission or Clutch problem???


Careless

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Hi everyone.

 

SO.

 

I finally managed to get my transmission off my 87 Z31 Turbo.

 

I took off the clutch to reveal that it's a UNISIA unit, which I believe is standard OEM. It's practically brand new. Nothing wrong with it. Infact, I'm considering just cleaning it up and putting it back on depending on what I can withdrawl from the hybridz mainframe of brains (you guys!).

 

Anyway.

 

I noticed 10 days after getting my car on the road and driving for maybe... 100 miles that going into gear while rolling was getting harder and harder. 10 days before that it was FINE. no grinding at all, not synchros yelling at me. Even trying to pull the the transmission out of gear was starting to feel "unnatural". It always had a clunk to it.

 

When I'm at a dead stop, it goes in just fine. No forcing required whatsoever.

 

It started to act up so I bled the system via gravity. Still, same problem. SO I decided to push out the pedal adjustment rod. Now I have the throwout bearing hitting making funny sounds. But still, same problem.

 

SO today I bought the transmission attachment for my large jack, got under there, pulled it off with my friend, and I find that the clutch is fine, except that the pilot bushing has a gouge in it. on the outer face of the pilot bushing there seems to be a scrape/gouge mark that shows the brass/bronze being eatin away. The input shaft that slips into the bushing also has a gouge at the hilt of the piece that inserts into the pilot bushing.

 

The input shaft has about 0.5 mm of play in all directions. I'm not sure if that's even worth mentioning, but I will. It's not as if it seems to be really bad or anything... somewhat normal for a 21 year old transmission.

 

The transmission even spins by hand in all gears. I drained the tranny fluid and purged it with some ATF poured through the shifter hole with the drain hole opened. I drained the ATF into a can and then poured the ATF back into the ATF bottle using a paper towel as a filter. There were TINY particles, but nothing to be alarmed about. No chunks. nothing more than say... the thickness of a hair.

 

The magnet on the drain hole plug had a lot of shavings on it too, but again, I figure 21 years of slammin' gears isn't going to be anything less.

 

My dilemna is now trying to find out what the problem is.

 

A friend of mine said that as he had his hand on the shifter while the car was idling, he could feel a spinning motion through the shifter. I know I felt it before too at one point. I'm not sure whether to suspect that gouge in the pilot bushing to be anything of concern :-(

 

perhaps some driveline shock?

 

I'm kinda depressed now. I was hoping it was going to be like YAY, A SPRING BROKE, TIME TO FIX CLUTCH... now i'm not so sure.

 

I got a taste of Z's for the first time, and only drove it for 10 days, and ... now nothing

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I'd also like to mention that there was a transmission flush about a year or so ago, maybe a bit more.

 

The clutch was done in 2006 at a local Z shop, and it looks to have been installed just fine. I have all the paper work and whatnot. Can't see anything out of the ordinary with any of the receipts at that time. The clutch disc, flywheel, and pressure plate look all perfect....

 

Except that there were very fine cracks in the flywheel. Could it be warping? Could the pressure plate case be flexing under the heat? There seems to be some burn marks on the flywheel. Well.. more like heat affected zones, but not severe burn marks of any sort.

 

The previous owner did say that since the clutch swap, it never did drive the same. I'm not sure what the hell to deduce by that :(

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Yeah, didn't work very well. Or maybe I'm not good at it.

 

It was hard pulling it out of gear too. Could it be possible that the synchros are "sticky"?

 

I got some redline MT90, but I'm not sure if I should just clean my clutch and put the unit back in the car. :-/

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Could it be that the pressure plate (while new) is defective, and does not release the clutch disc?

 

How could I test the pressure plate? I remember after adjusting the pedal-rod, the throwout bearing was scratching against the pressure plate fingers.

 

I don't know why it would scratch so much, that sounds to me like there's no give to the pressure plate.

 

:icon11:

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I should not be offering to much advice here since I'am not nearly as quilified as some members.

No problems with engine running at a stop. Assuming clutch and tranny were warmed up and at a stop no problems, were you complety engagaing when shifting between gears?

I know most people like my self will not fully push that pedal down while driving.

I believe that if you had no problems at a stop with shifting between gears (with engine running) and did not feel any radom grabing you would not have any clearence problems with the clutch assemble.

The only difference is that things are moveing faster while driveing and stuff is turning in the transmission that is not while sitting still.

 

Soooo mabey you have a thrust bearing worn, or something is wearing out causing alingnment issues that would be "loose" but not too badly worn.

 

Then again I might be all washed up here.

Etheir way not much help.

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Yeah, just normal driving. Fully depressed clutch pedal. I even adjusted the push-rod so that it's at max.

 

I'm not sure what to think right now. It seems as though the clutch never disengages completely, almost like the pressure plate is stuck.

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Yes, but won't that cause grabing at a stop while in gear?

I know on our nissan work rigs, 2wd that we have owned and used for 20years, the bearings always fail.

My last pickup started to do a few odd things than whammmo, lost main bearing. There was really no ware just metal fatigue on the keeper.

Had another one do similar. OUt on the freeway no problems, came off the ramp and could not get it out of 5th gear!!

It's just that I would expect that It would grab at an idel as well as moving.

 

How come no one esle is chiming in hear while I stumble all over??

I can just see the giggleing in the back ground.

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  • 3 weeks later...

lol yeah most of what i read is "the FS5R30A can nevAr brokes!11!!!"

 

I think either the damper or the slave are internally messed .perhaps not releasing at full load. I got a stainless line now, so that should be ok.

 

Also got my Fidanza Flywheel and F1 Racing Clutch, which is a SECO unit with a carbon kevlar disc.

 

Looks good.

 

Also came with a new nissan bearing, but I ordered a new nissan bearing and collar together... so right now I have the following parts ready for going in:

 

1) crossover pipe studs

2) crossover pipe gaskets

3) new OEM flywheel bolts

4) new OEM pressure plate bolts

5) new pivot ball stud

6) new clutch fork

7) new clutch fork bearing retainers

8) new throw-out bearing

9) new pilot bushing

10) new rubber fork/bellhousing boot

11) new stainless clutch line

12) new flywheel

13) new clutch and disc

 

is there anything else that I'm missing? I'm going to pick up all the bolts and stuff tomorrow.

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You must feel like a kid in a candy store!!

 

I will have to admit, hopefully everything that might have been a problem was external to the tranny.

 

In hindsight (rereading your post again) seems to be the correct course of action. Best of luck sir!

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I personally think it's the pressure plate.

 

I tested my theory. get this:

 

Clutch was not letting go. Something weird was happening. I bled the system and it was pushing the fork all the way.

 

I adjusted the pedal adjusting bolt, and it was pushing the clutch master pin to the max.

 

It was still being testy.

 

I noticed that If in an empty parking lot at 1 in the morning, I was able to circle the ENTIRE parking lot @ 7 KM per hour, without ever pressing the gas once. I just let off the clutch pedal really really slowly. But this car's got torque so I didn't think anything of it.

 

Now with the pedal rod adjusted to max, fork moving max, I noticed that sometimes if I stepped on the pedal REALLY hard, all the way down, the throwout bearing would lock itself against the pressure plate, and start to make a roller-skate wheel sound, or a slight metal rubbing sound.

 

After removing the trans... I noticed that if I were to pivot the fork to MAX possible, the throwout bearing has two hard cut edges on the inside of the bearing collar that get STUCK on the end of the input shaft sleeve, and sorta grab the edge of the sleeve and keep the throwout bearing LOCKED at the edge of the sleeve...

 

So I think that no matter how hard the pressure plate was being pressed, it was not fully releasing the clutch for some reason.

 

My flywheel was probably expanding due to heat, as it has some slight cracking... and my pilot bushing has a tiny grinding mark on the edge of the pilot bushing, and the input shaft has a bit of a ground-in mark there too, so it was probably catching that point of the pilot bushing and almost acting like a ratchet, in that it catches the little piece and spins in it's direction with the right amount of force not to break off another piece of the soft bearing, but enough to keep the trans moving.

 

 

We'll find out what the F is going on by the end of the week. That's when it's going all back together hopefully. :-)

 

I go to get the other parts tomorrow! I know what you mean about it being outside, that would have been great. I'm removing the damper too, so my shifts will be more direct.

 

But... now I got a lightened flywheel, and It has all new ignition parts and stainless lines on every brake/slave....

 

I'm at about 2700 in total, car included. I think for the price, and the amount of compliments I've gotten on it already, people seem to think it's a good car =)

 

Raff.

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no sorry if i made it seem impossible.

 

on the end of the input shaft, just before the taper... there is a small grinding mark. it's a friction area that looks to be in line with a portion of the PILOT bushing that also has a grinded edge. It could be possible that the pilot bushing and input shaft sometimes catch there, and continue to spin.

 

WHO KNOWS!

 

On a side-not... can one re-use clutch pressure plate bolts? or should I replace them?

 

They were on back order. Everything else was there.

 

:-/

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Very interesting.

 

Dose the new pressure plate have the same engaged pressure as the one removed? Are you like me and are hard on your equipment?

 

Personally the bolts see most load in a sheering type of torque. Due to the cracking of the fly wheel I understand replacing them but don't really see the need to replace pressure plate bolts.

 

I hope some one with more experience would chime in on that question.

 

As far as karma goes, wait and get the new ones OR ELSE! (since you have thought about it and asked, if you had left the subject alone you would have been fine)

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As far as karma goes, wait and get the new ones OR ELSE! (since you have thought about it and asked, if you had left the subject alone you would have been fine)

 

now that's doubley true cause your posted the truth in a public place! :icon_frow

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AAHHHHHHH MAANNNN! Did not think of that.

 

Sorry.

 

Ya know this seems to be some kind of private thread.

 

If that is the case, how's it going? Work been good for you? The whether has been fantastic around here.

I will be stating on my other dormer soon in order to increase living space for my son as he grows.

 

I will post some pics of before and after:)

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Ya know this seems to be some kind of private thread.

 

If that is the case, how's it going?

Swell.

Work been good for you?

So so. Getting a little annoyed with current web projects led by other people.

The whether has been fantastic around here.

It's been rainy for the passed couple of days, but I nap through the storms and work through the sun. Not my idea of 'Time Management'

I will be stating on my other dormer soon in order to increase living space for my son as he grows.

I'm going to be doing the same for my land-lords boat.

I will post some pics of before and after :)

before and after the rennovations, or before and after your son grows.

what year can we expect a resurrection of this thread, if the later?

 

:hijack:by ourselves

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OK SO...

 

tried to weld a nut onto the stud to wrench it out, and the stud broke 2 threads off the tip. the welding had super heated it with immense redness!

 

still no budge. so the last resort is to basically take the passenger side manifold off, clean the head mating surface, clean the manifold mating surface, remove the studs by using a super duper torch and then removing the other two studs off the driver side manifold. then I'm going to put it on, and then finally put that ♥♥♥♥♥♥♥ clutch back on so I can drive this thing.

 

I hope it works for me =(

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Frist of all WHAT bolt?? I read both posts and mabey Iam stroken, but I can't figure that one out. Needless to say old el carma might have caught up with you (hopfully not me) for that thread concering a stuck filler plug?? :)

 

 

 

Anyhow.... Friday Starting at 3;00pm

 

Dormer082Medium.jpg

 

Saterday

 

Dormer086Medium.jpg

 

 

 

 

Dormer190Medium.jpg

 

 

And I missed sunday's shot. It was mostly sheeted, the roof after the the 2x6 rafters were sistered up to the old 2x4s.

 

Jim, my neibor is helping me, very fine man! (Old school)

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