Clutch Pedal Pressure Issue

[iamtheyi]

Lately I have been having an issue with the pressure of my clutch pedal. My clutch pedal engagement likes to move around a lot when I start to drive. It will at times move the engagement point just short of the top of the clutch pedal travel and sometimes it will drop just short of the bottom.

I have noticed that when I do a hard pull onto a freeway on-ramp, the clutch pressure will drop closer to the floor. It only comes back when pumping and forcing full movement from the bottom of travel, and pulling it back all the way up with my foot.

My clutch kit is about 1.5 to 2 months old. This problem persisted with my old master and cylinder so I replaced them about two to three weeks ago. The problem was temporarily relieved until about two days ago.

I have a 1995 Nissan 240sx with stock KA24DE. The clutch dampening box has been deleted.

[drifter1992]

did you try bleeding the system? you could have air in the lines

[iamtheyi]

That I did sir.

[iamtheyi]

Anybody have any solutions? Pedal falling to the floor again after driving on the freeway for about 15 min. Went to go depress the clutch to put the car into neutral and basically no pedal pressure. Had to pull it up with my foot to increase pressure enough to take the car out of gear.

When I had come to a stop at the light, I smelt what I think was burning clutch.

[godrifttoday]

Sounds like your slave... And how u bleed the system?

[iamtheyi]

Sounds like your slave... And how u bleed the system?

I just replaced the slave. But, I had a friend pump the clutch, hold it down, open bleeder screw, then close it.

[revert]

Repeat... Repeat ... Repeat... Should get better

[iamtheyi]

adjusted the engagement point with the rod on the Clutch MC and it worked for a little then pulled. Just bled it and pressure is all back. Will report back to see if it was a temporary or permanent fix.

[g00se]

any leaks?

[iamtheyi]

any leaks?

So far there are none that I can visibly see from the master or the slave. The lines seem to be okay too. Fluid level is constant.

I did notice another thing. My softline going to the slave cylinder could have used a little more tightening (not loose but could torque it down a little bit more) so I tightened that up a little bit too.

[iamtheyi]

still having problems with the clutch pressure changing all the time. Ambient temperature also changes feel.

Any thoughts?

[terrymotorsports]

If you have no leaks get a handy bottle man that wont let mc go dry get a cup with brake fluid in it route some vaccum line from bleeder screw to cup crack bleeder and pump to your hearts desire close bleeder pump once pick pedal off the floor and your good

[terrymotorsports]

If problem persists with no leak you are experiencing clutch fade at that point your making too much power for the pressure plate overheating it causing the spring steel restpoints to change

[iamtheyi]

Terry, none of what you said pertains to me. I know how to bleed my master. I also don't have "too much power". I'm stock KA.

bump again. Replaced the Clutch Master again and it did it again. If I adjust the clutch master a little bit too low, it loses all pressure and basically sinks to the floor. If I adjust it to where I like, it gets stiffer and the engagement point rises to almost the top of the travel when I start driving. It's ridiculous.

[KiLLeR2001]

Are you replacing the clutch master/slave with autozone parts or OEM replacements from the dealership? Slave cylinders from autozone / local parts store never seem to last for me, OEM much better.

Also, do you have the exhaust manifold heat shield installed? Too much heat may be causing the fluid to overheat, I'm assuming you have no troubles with pedal feel when the car is cool?

[iamtheyi]

I am currently replacing both the slave and the master with vatozone products.

Also, I do have the heat shield installed but you are correct in saying that I do not have a problem with pedal feel when the car is cooler.

[jr_ss]

bump again. Replaced the Clutch Master again and it did it again. If I adjust the clutch master a little bit too low, it loses all pressure and basically sinks to the floor. If I adjust it to where I like, it gets stiffer and the engagement point rises to almost the top of the travel when I start driving. It's ridiculous.

So, if you leave it at this point you have plenty of pedal pressure to operate the clutch, you just don't like it's release point?

[iamtheyi]

So, if you leave it at this point you have plenty of pedal pressure to operate the clutch, you just don't like it's release point?

It's not that I don't like the engagement point, it moves upward along the travel of the clutch as I drive. I have a paranoid feeling that the throwout bearing is resting on the pressure plate because it is engaging so high.

Basically when I start driving, there is about 1 in free play in the clutch pedal. After cruising for a bit more, there is no free play.

[jr_ss]

Try adjusting your rod all the way out of the MC, meaning you'd have a lot stick out in the cabin. Rebleed it and see what it does.

[iamtheyi]

I have done that before already. Problem persists.

I already have most of the rod sticking into the cabin. If I adjust the engagement point any lower, it won't hold pressure.

[jr_ss]

Did you bench bleed the MC before you installed it?

[iamtheyi]

I did bench bleed it sir.

I checked the master today and the fluid is already getting darker. I installed it last week. This is bullshit. You guys think that the autozone master and slaves are just big pieces of shit even brand new?

[terrymotorsports]

Yep they are only last about a year your dark fluid comes from your soft line that's normal how much fluid did you push through the system and was it a freshly sealed bottle

[iamtheyi]

Yep they are only last about a year your dark fluid comes from your soft line that's normal how much fluid did you push through the system and was it a freshly sealed bottle

lol. I put in the clutch slave cylinder last month. It was a fresh bottle of brake fluid. I always use a new bottle when bleeding or installing new clutch hydraulic stuff. I know about it absorbing water/moisture in the air when opened.

I bled it until all my old fluid was out and the fluid coming out was new.

You think my soft line going to the slave cylinder could be bad somehow? This crossed my mind couple times but I didn't have any evidence it could be.

[terrymotorsports]

If your sitting still before you drive and pump the clutch does it get stiffer than the initial depression I had this similar problem about 8 years ago ran a big bottle of fluid through the system using Line in container of fluid it eliminated my one inch free pedal issue and no longer had thermal expansion (ambient temperature variance) I have never had a Nissan clutch bleed properly by the pump hold method I change my slave once a year because advanced sucks all your symptoms point to air or moisture in the system I'm not crazy I'm ase master automotive technician in all categories and spent six years in the dealerships

[terrymotorsports]

It's possible your softline could be Bad but not likely Get a friend to depress pedal while you watch the line for excessive expansion I got tired of dirty fluid and made a braided line plus it helps with pedal feel

[iamtheyi]

If your sitting still before you drive and pump the clutch does it get stiffer than the initial depression I had this similar problem about 8 years ago ran a big bottle of fluid through the system using Line in container of fluid it eliminated my one inch free pedal issue and no longer had thermal expansion (ambient temperature variance) I have never had a Nissan clutch bleed properly by the pump hold method I change my slave once a year because advanced sucks all your symptoms point to air or moisture in the system I'm not crazy I'm ase master automotive technician in all categories and spent six years in the dealerships

Okay. I would like to just say:
#1 What the fuck are you saying? Can you use periods please?

#2 I tried to read what you are saying, and I mean really try, but I still don't really understand what the hell you are trying to say.

#3 All I see is "I'm not crazy I'm ase master automotive tech [who doesn't know how to type in coherent sentences to get my thoughts across and doesn't know how to use periods]" (ASE master technician doesn't really hold any weight with me. I know plenty who have that certification that diagnose cars incorrectly and are extremely closed minded to any sort of guidance. Meaning they are prideful, pompous assholes)

#4 I appreciate your help Terry. But I do not understand you.

[terrymotorsports]

Okay. I dropped out of school. I didn't think punctuation was necessary to help you. Just as I was unaware profanity is necessary to Get a point across. I offered you potential solutions to your issue without condescension. I accept guidance just fine and help fellow enthusiasts diagnose concerns. I began a career in the automotive industry as an apprentice. I didn't get my certifications through automotive technology programs. I learned on the job so yes I can diagnose.

#1 check your soft line for excessive expansion when you depress the pedal....

#2 you probably still have air in the system.

#3 get a container of fluid... place a hose from bleeder port into the container... open the bleeder... pump the pedal while someone keeps the master cylinder full using a big bottle of fluid until it is gone... close the bleeder screw and you should have a properly bled clutch.

#4 good luck and don't be a douche when someone takes their time to offer you help

[iamtheyi]

#1 check your soft line for excessive expansion when you depress the pedal....

#2 you probably still have air in the system.

#3 get a container of fluid... place a hose from bleeder port into the container... open the bleeder... pump the pedal while someone keeps the master cylinder full using a big bottle of fluid until it is gone... close the bleeder screw and you should have a properly bled clutch.

#4 good luck and don't be a douche when someone takes their time to offer you help

I will check the softline for expansion. That's the one thing I haven't done because I can't get under the car while pressing the clutch lol; however, I did bleed my system exactly the way you described. Got a hose from the slave to a bottle of fluid while pumping the clutch and keeping the M/C full.

I appreciate your help. I use profanity in typing because I use it in real life lol. I cuss a little more than I should :). I wasn't trying to be a douche. I apologize if I came across as one :p

I numbered my sentences to organize my own thoughts and separate the different ideas I had. But seriously, I can understand you now lol.

[terrymotorsports]

Iamtheyi,

No worries brother, I'm a special forces vet with extreme ptsd. I understand fully and struggle not to be profane on this site bc I don't want kicked off lol. I do often need advice to save hours with a meter and my car from my sledgehammer (it happens when I get angry with my own stuff.) Good luck, and I hope you get it fixed soon I hate when my toy is broken. I will check for service bulletins regarding this concern.

[iamtheyi]

Changed the clutch line with a SS one and the problem is still there. Colder weather, pressure decreases. Warmer weather and after the car warms up, pedal stiffens. Went to the track day and clutch was still grabbing even while very stiff.

Any more ideas? Friend suggested that I used the wrong grease on the throwout bearing and transmission shaft and that's leading to the bearing not being able to move easily.

[jr_ss]

What type of clutch are you using?

[iamtheyi]

Competition Clutch Stage 1 for KA24

[slideways40]

I am having 100% the same problems with my ka-t with the clutch. I have a brand new master, slave, clutch, and new SS clutch line. Still cant figure it out. Only thing i can think of is the pressure plate not holding bc when mine does it it wont even brake the tires loose. When it doesn't do it tho i have no problem breaking them loose.

[h2v7]

yea adjust pedal and bypass clutch dampeneer


also get a new stainlesss line from a new master to a new nismo slave it will fix this

[iamtheyi]

So basically you are saying that replacing my hardline will get rid of this problem? For some reason I highly doubt that.

I have adjusted my clutch pedal numerous times and I bypassed the clutch dampener a long time ago.

[jr_ss]

So basically you are saying that replacing my hardline will get rid of this problem? For some reason I highly doubt that.

I have adjusted my clutch pedal numerous times and I bypassed the clutch dampener a long time ago.

I don't see replacing the hardlines with a SS line fixing the issue. I have an Exedy twin disk on factory MC, slave and hardline without a problem.

How much slop do you have on your pivot arm/TOB at rest? Next time you notice the clutch issue, check to see if that has changed. Your TOB rod isn't bent is it?

[slideways40]

So basically you are saying that replacing my hardline will get rid of this problem? For some reason I highly doubt that.

I have adjusted my clutch pedal numerous times and I bypassed the clutch dampener a long time ago.

I have the auto to manual conversion clutch line and it does the same as yours so changing the line will not fix it

[iamtheyi]

I don't see replacing the hardlines with a SS line fixing the issue. I have an Exedy twin disk on factory MC, slave and hardline without a problem.

How much slop do you have on your pivot arm/TOB at rest? Next time you notice the clutch issue, check to see if that has changed. Your TOB rod isn't bent is it?

Could you elaborate what you mean by slop on the pivot arm and TOB at rest?

My TOB rod is not bent. If it were, I don't know how that would affect it the way it's affecting my pedal?

[jr_ss]

As in, when you are not pressing on the clutch pedal, how much play do you have between the slave and the PP fingers. Can you wiggle the TOB arm forward and backwards in the direction it typically moves?

[Sliderintrainin]

subscribed!



i have the same issue. still trying to figure it out as well.

[iamtheyi]

How am I supposed to know how much play there is between the slave and Pressure Plate fingers? They don't even touch. I can not move the TOB arm forward in the direction it moves.

[jtaylor]

when I push my clutch in to shift it does not come out all the way. I found out one night that the previous owner had wrapped a bungee cord around the very top of the clutch so it would disengage fully. Now while shifting and pushing the clutch in all the way down and shifting i sometimes grind the gears. While shifting i can feel the gears spinning and have to wait till they disengage so i will not grind while shifting. Have you tried replacing the clutch, flywheel, pressure plate, and throwout bearing to ensure all are new? I will have to wait till I will be done training in the field before I can change all those out. With also the master cylinder and lines.

[jr_ss]

How am I supposed to know how much play there is between the slave and Pressure Plate fingers? They don't even touch. I can not move the TOB arm forward in the direction it moves.

So you cannot move the TOB arm that protrudes from the side of the trans either forward or backward? It should be marginal at best, so you really shouldn't see much movement. I'm just trying to get an idea and rule out things it could possibly be.

[h2v7]

NISMO slave!!!!!!! + brand new nissan master

[iamtheyi]

when I push my clutch in to shift it does not come out all the way. I found out one night that the previous owner had wrapped a bungee cord around the very top of the clutch so it would disengage fully. Now while shifting and pushing the clutch in all the way down and shifting i sometimes grind the gears. While shifting i can feel the gears spinning and have to wait till they disengage so i will not grind while shifting. Have you tried replacing the clutch, flywheel, pressure plate, and throwout bearing to ensure all are new? I will have to wait till I will be done training in the field before I can change all those out. With also the master cylinder and lines.

I replaced the clutch myself. I am definitely sure they are new lol. and I also don't have a bungie cord in my tranny hahaha.

So you cannot move the TOB arm that protrudes from the side of the trans either forward or backward? It should be marginal at best, so you really shouldn't see much movement. I'm just trying to get an idea and rule out things it could possibly be.

I can move it back but that just pushes into my slave cylinder?

NISMO slave!!!!!!! + brand new nissan master

I actually read another thread that had a guy do that but did not alleviate the problem.

[jr_ss]

I can move it back but that just pushes into my slave cylinder?

I actually read another thread that had a guy do that but did not alleviate the problem.

Yeah if you push on it hard enough it will, I'm just talking about the "slack" persay.

Nismo slave's are more commonly swapped on for heavy duty clutches, not because pedal pressure changes while you are driving.

I recall you stating your fluid was already changing colors after installing the MC a week prior. Have you since replaced it? I would buy an OEM MC and go from there. Sometimes it's impossible to actually pinpoint the problem. I'm still leaning towards the MC leaking down/drawning air into it. Have you noticed any leaks inside the cabin coming from the MC?

[iamtheyi]

Yeah if you push on it hard enough it will, I'm just talking about the "slack" persay.

Nismo slave's are more commonly swapped on for heavy duty clutches, not because pedal pressure changes while you are driving.

I recall you stating your fluid was already changing colors after installing the MC a week prior. Have you since replaced it? I would buy an OEM MC and go from there. Sometimes it's impossible to actually pinpoint the problem. I'm still leaning towards the MC leaking down/drawning air into it. Have you noticed any leaks inside the cabin coming from the MC?

Guess I'll take a look into the slave and clutch fork when it stops raining in a couple days when I get a day off work also.

No leaks inside the cabin from the master. But it does seem like the seals on the master or slave go out rather quick seeing as how the fluid gets dark quickly. I've been holding off on the OEM master and slave because they're like 100 dollars each lol. I'd rather buy tires but what can I do.

I have wheel bearings to replace too. Cars...

[Foolish]

Pretty sure the answer has been given, I was having the same issue, replaced Slave Cyl, didn't work, bled everything, didn't work!

Delete the clutch dampener and replace the clutch master cylinder and everything should be PERFECT! :)

[brianksm]

I had the exact same issue and ended up replacing the master, slave, deleting the clutch dampener and hardlines with an agency power 52" ss clutch line, bled it and problem was solved. Later noticed a pin hole in my slaves rubber boot.

[iamtheyi]

I have found the problem. It WAS the Clutch Master Cylinder. How disappointed I am lol. So anyone who is having the same problem can diagnose.

[Foolish]

Glad everything worked out! I felt pretty stupid when I figured it was mine, instead of replacing that I did everything else BUT that. /: silly s13s

[racers4life77]

I had the same issue with 3 of my remanufactured CM cylinder from the parts store. So i decided to tear each of them down and find out what was failing.
Attached to the piston is a valve that lets fluid in when you let go of the pedal, this little valve went bad in all 3 of my reman CMC in my car in less then a year, very frustrating!
So i bought a( MASTER CYLINDER REPAIR KIT) for about $18 from Nissan and put in the reman cylinder and works perfect.

[jtaylor]

I bought the master and slave cylinder to replace the old ones and now it works like a champ.

[xMOAR LOW S13x]

this might not be the problem but, are you shure your throw out bearing isnt bad. it shouldnt really affect pedal pressure but it could affect how and where the clutch engages.

[iamtheyi]

I am 100% sure. Bad throwout bearings make a discernible noise.

[joker1984]

Iamtheyi,

No worries brother, I'm a special forces vet with extreme ptsd. I understand fully and struggle not to be profane on this site bc I don't want kicked off lol. I do often need advice to save hours with a meter and my car from my sledgehammer (it happens when I get angry with my own stuff.) Good luck, and I hope you get it fixed soon I hate when my toy is broken. I will check for service bulletins regarding this concern.

Special forces vet... See it's people like you who give us a bad name nobody asked for the sympathy game... Thank you for serving by the way I've been active duty for 9 1/2 years as well with two deployments don't use that as an excuse on these social media sites it's pathetic... I'm tired of see this crap on Facebook an every where else keep it to ur self most of us who deployed have PTSD.. An here's a true fact you don't have to go to war to get PTSD. So stop using it as an excuse thanks... Sorry everyone this just has Ben bugging me.