FR-S Extreme Clutch Problems
 

Hello all, I just joined this forum today in order to get some help on some extreme clutch difficulties I have been experiencing. I have searched far and wide to no avail and have changed quite a few parts in the process. Bear with me and read it all if you can, it is pretty in depth. And for god sake's please don't just give me the "bleed the clutch, its the TOB, adjust your pedal bs" before you even read what I have to say.

Three months ago I purchased a used 2013 FR-S, before that I had a 2014 FR-S that was totaled. The vehicle seemed in decent condition at the time, it had dings here and there but overall the engine seemed well and the previous owner swapped the fuel pump out (bye bye annoying chirp!). Everything was dandy until about 300 miles off of the used dealership lot.

I started to notice a chirping sound similar to the fuel pump chirp, yet this one was metallic in nature. It was much louder than the ones I had heard before. Me being quite sensitive about my cars well being, I popped the hood and listened in. After some looking around I noticed that the clutch fork was wiggling left and right, and it was squeaking like crazy! To make matters worse, pushing in the clutch alleviated the noise.

At this point I decide, it is definitely the TOB, I will order a new clutch and have it replaced ASAP. And so I did. In the process I bled the clutch, replaced the transmission fluid, reattached a new Exedy OEM copy TOB, Clutch Plate, and Clutch Disk, and went on my merry way. Except.. I didn't go on my way.

After the install, the car would not go into gear, and in my head I instantly thought to the clutch needing another thorough bleeding. I did so, and viola! The car sat right into gear like it should have in the first place, but everything was not so great. The squeaking was worse than ever - and not only that, but every time the car was stopped and restarted the clutch needed another bleeding.

At this point I was certain the slave cylinder or the master clutch cylinder was bad, so I started by replacing the slave cylinder - and additionally adjusted the clutch pedal to try and find a spot where the clutch would properly disengage..

Here's where things started to get weird.

The clutch began disengaging at different heights on the pedal, sometimes it wouldn't disengage at all. The squeaking became absolutely horrendous, so I decided to squirt some high temp grease into the clutch forks boot. It did help a bit, but it is not completely gone. The car is now completely immobilized due to the fact I cannot get it in gear. No matter how many times I bleed the clutch, or adjust the master plunger, or gravity bleed the entire clutch system. The clutch pedal is also much softer than it originally was, however it still does take a little bit of pressure to get it all the way down. Meaning that it still has pressure in the system, just likely not a lot of it.

So far I can only come to possible the conclusions that:
1. The Master Clutch Cylinder is bad in some way. However I have visually inspected the reservoir whilst the clutch pedal is depressed, and the liquid inside does not change levels.
2. The lines between the MCC and the Slave are leaking in air so badly that the system cannot function. However I have vacuum bled through the slave nipple and no air seems to come through.
3. Something inside the clutch itself has malfunctioned. However, the entire system, save the flywheel and clutch fork are brand new.
4. Brake fluid is absolutely everywhere at this point and I just want to drive my car again.

Any insight or answers are gratefully appreciated, and if you have similar problems, head to the end of this thread and I will do my best to have the answers posted.

Hello Japanese_Carbon and welcome to our fine forum … :clap:

What a go round you are having with your clutch .. :(

As you suspect, I would suggest you replace the clutch master cylinder. I would also order an aftermarket reinforced clutch fork (just in case the old one is stressed out).

Having said that, I'm going to refer you to our clutch expert, ol @Ultramaroon .

He has been a bit cranky here lately, but, hear him out.

I hope you get it sorted out soon.


humfrz

Thank you for the input and the welcome!

I do believe you may be correct about the master, as some symptoms do point to that, but just as well I believe it could have something to do with the fork. Hopefully the clutch expert has some further insight. If not, I suppose its up to luck of the draw buying parts until the problem is fixed. Thanks again!

What squeaking? Did you replace the clutch yourself?

The level in the reservoir does not change as the clutch is operated. That's not how it works.

However, if you pull the fork all the way forward to compress the plunger in the slave, that fluid will flow back into the reservoir. Then you have to wait for everything to flow back into equilibrium, or pump the pedal a couple times to help it along.

There should be no squeak. Post up a video clip of the sound.

Sure thing:

https://streamable.com/s/ekjdx/xhgbnd

Note that the video also includes me depressing the clutch pedal multiple times to show the alleviation of the noise.

Although I can understand your frustration with the fact that the reservoir liquid levels do not change, I simply stated that the levels weren't changing, therefor indicating that there was no weird issue where the liquid was being forced back up upon depression of the clutch pedal.

However, the clutch was replaced by myself, and the squeak was there before, AND after the replacement. The squeak itself is primarily produced from the location of the clutch fork.

Unfortunately the concern lies mostly with the fact that I can no longer disengage the clutch to get the car in gear, and less with the fact that the clutch fork is squeaking. Unless of course you believe they are correlated.

The squeaking in the video sounds like my clutch fork squeaking (I can only hear it when my car is in the garage or up against a wall). I understand that can be fixed by greasing it up.

As for your major problem, I'll still put my money on a bad master cylinder (in light of all the bleeding you have done along with replacing the slave cylinder).


humfrz

I'm not frustrated at all. I'm just being direct. Humfrz was flipping me shit about being cranky.

Sounds like the crickets. Does it make the noise immediately upon startup, or only after it has been running for a while. That's an excellent recording. I can hear your DI system operating. That lends some weight to the cricket observation. I hear zero issues with TOB or fork creak.

Now, on to the clutch disengagement issue. Where does the clutch pedal come to rest in relation to the brake pedal right now? Unless it is already significantly higher than the brake, humor me.

Loosen the cruise defeat switch and back it way out. Then adjust the pedal up high. Does your clutch now disengage?

1. The noise occurs immediately upon startup, and regardless of the engines temperatures the sound does not change.
2. The squeaking can be stopped by resting my hand upon the top of the clutch fork, or engaging the clutch pedal (thus pushing the clutch fork forward).
3. The clutch pedal is raised all of the way, meaning I have utilized the U clip at the end of the master plunger to raise the pedal, and have backed out the defeat switch all of the way.

On the note of pedal adjustments, for a while the solution you provided to disengage the clutch DID work (this was something I had tried on my own before asking), however the problem seems to have escalated beyond the point where the pedal can be raised to disengage the clutch.

Do you believe this problem could lie with the Clutch Master Cylinder?

Thank you for your patience with me.

:D


humfrz

Bah! No patience required! Thanks for being an excellent communicator.

The threaded u-clip is called a 'clevis' Then there's the clevis pin, and the whole thing is called a clevis joint.

...whoops-NVM this one. I gotcha on the second read... So, going back under the hood... With the engine running, if you manually pull the top of the fork forward to back the TOB away from the pressure plate fingers, does it stop squeaking?...

When you push away on the fork, does it feel like the TOB is making solid accurate contact with the pressure plate fingers? Do you feel any wobble while it's in contact?


I'm not yet ready to make a call on the master cylinder. If it was leaking, there are only two places the fluid could go; back into the reservoir, or into your carpet. Neither seem to be the case.

Sorry about the wait! I actually had the vehicle towed today to a shop that is going to take everything apart and look at it.

In the meantime I have my speculation and, while I had the vehicle I did mess around a bit with the fork and hydraulics. When tugging the fork back towards the slave, it did feel solid, and just as well pushing it forward seemed to create a solid contact between the TOB and pressure plate fingers.

I am unsure as to what exactly a solid feeling would appear to be, however there is no wiggle room left and right once the fork is moved forwards or back.

In other news, I removed the entirety of the clutch hydraulics, and took it to the shop for them to diagnose. However, they concluded that the system was fine and intact. I suppose we will have to await the removal of the transmission, and likely the inevitable thinning of my wallet. :cry:

I always like simple first.
You have been looking at the fork, did it move the same distance before and after each bleeding? If no then there is a problem with the hydraulics. If yes then a problem with the mechanical part ie. fork bearing or pressure plate.
I have had times when slaves will not expel all the air and had to be filled on the bench. Very unusual for a clutch system to suck air in after bleeding as it is under pressure from the pedal on the return stroke.
Many strange thing have happened to forks, bearings and pressure plates. Turns , shifts, and broken springs among them.


Beyond that you maybe "lucky" enough to have more than one problem at a time.

I'm having the SAME issue after swapping out my TOB & clutch.
Did you ever find out what the problem was?

So did anyone get an answer to what the issue was? I’m having very similar issues after changing my clutch, flywheel, and throw out bearing as well.