Clutch suddenly lost pressure, won't engage while running.

[Forced4dur]

Hey everybody, looking for a little help from someone a little more knowledgeable than myself on an issue I'm currently having concerning my clutch.

The clutch in my VR4 suddenly lost pressure, but there is still very slight resistance, and wouldn't shift unless forced in. Athough I only had to drive like this for about a mile to make it back to the house.

The car shifts into gear fine with the car off, and can be clutchless shifted by Rev matching I unfortunately had to find out. I'm just not sure why it would instantly lose pressure like it has. On a possibly related note right before it happened I had to ride the clutch because of what I think is a fueling issue causing the car to lose all power every few seconds until I push in the throttle a good amount and it comes out of it. I figure it may be a clogged filter since I made the switch to e85 and have yet to change to the SS element.

A little background on the car is according to the PO it has under 20k miles on:
-New oem slave cylinder
-New oem clutch master cylinder
Ss clutch line
-Act chromoly lightened flywheel with arp hardware
-Southbend clutch with kevlar disc

Around a week prior I hit a large pothole backing out of a driveway and the clutch wanted to occasionally slip at high rpm, not sure if it's related but I figure too much information is never a bad thing.

I'd love to be wrong but I'm leaning away from it being a hydraulic issue because I am not losing any fluid, my master and interior is dry, slave cylinder still moves when the clutch is pushed in and is also dry, and have recently bled the clutch. My thinking is it may be the fork or pivot ball? The clutch fork seems to rest in about the center and have a decent amount of travel.

It may also be worth noting my adjustment rod on the master is almost completely backed out on my pedal assembly, I assume VR4s share the same assembly as the 1g so it may be time to replace that as well.

If any more information is needed please don't hesitate to ask, I'm sure I left out something. Thanks!

 

[GST with PSI]

Does the clutch fork return if you push the fork/slave rod into the slave?

 

[dexterholland04]

Clutch fork should rest slightly towards the driver side. I would start with the fork. If you take the slave off, does it wiggle? If so, then your pivot ball is bad. Did you shim your pivot ball at all? I'll start there...

 

[Forced4dur]

Does the clutch fork return if you push the fork/slave rod into the slave?

It does, but it seems to have hesitation occasionally halfway through. OEM slave will be here tomorrow, thought I would start there. Especially since on .org the slave went out sometime in these 20k miles and am not sure if it was replaced with OEM, but it looks like it.

Clutch fork should rest slightly towards the driver side. I would start with the fork. If you take the slave off, does it wiggle? If so, then your pivot ball is bad. Did you shim your pivot ball at all? I'll start there...

I haven't removed the slave yet, just the first steps to troubleshooting really.

In all honesty the fork might be towards the drivers side a bit, I'll grab a picture after work today. Although I tried to move it and there is SOME front and back play in the form, but it is pretty minor.

I'm just lost because it happened while riding the clutch, and I figure if anything broke internally I'd still have pressure and engagement issues even without using the clutch.


And I appreciate the responses guys! I was scared I was too long-winded in my post

 

[dexterholland04]

It does, but it seems to have hesitation occasionally halfway through. OEM slave will be here tomorrow, thought I would start there. Especially since on .org the slave went out sometime in these 20k miles and am not sure if it was replaced with OEM, but it looks like it.



I haven't removed the slave yet, just the first steps to troubleshooting really.

In all honesty the fork might be towards the drivers side a bit, I'll grab a picture after work today. Although I tried to move it and there is SOME front and back play in the form, but it is pretty minor.

I'm just lost because it happened while riding the clutch, and I figure if anything broke internally I'd still have pressure and engagement issues even without using the clutch.


And I appreciate the responses guys! I was scared I was too long-winded in my post

No problem. I diagnose clutch issues like this:

- Inspect everything (look for the obvious, and the broken/out of place)
- Bleed it
- Adjust it
- Test it

Take good notes, too. If it isn't a simple adjustment issue, then having good notes will help you and help us help you!

 

[Forced4dur]

I'll be putting a speed bleeder on the new slave to help bleeding. If it doesn't fix things, which I'm not holding my breath at this point, I'll report back after adjustments.

 

[twicks69]

The speed bleeder can draw air in to the system, you are better off using the stock bleeder.

 

[Forced4dur]

I stand corrected.

I'll go make a friend to help bleeding the new slave. That could've been alot of chasing my tail, appreciate the heads up!

 

[Forced4dur]

Ok, sorry it took so long, it was a rainy mess outside. Pictures aren't the greatest due to the crossmember being in the way, but can definitely get better ones if needed. Looking at it, it seems like the master possibly isn't pushing quite enough due to my adjustment rod being almost out of threads, or the ball needs shimmed, as it looks like my slave isn't pushing all that far on the fork.



Clutch is not depressed here

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Clutch is also not depressed here.

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Acidentally a good comparison picture of not depressed vs depressed.
This is not depressed.

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And here the clutch is pressed in.

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Slightly better angle of the clutch pressed in.

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[Forced4dur]

Small update.

Slave came in yesterday, but I've decided not to half ass things and JNZ is sending me an OEM master when they get it in on Tuesday.

The master cylinder that is currently on it has me questioning if it's actually an OEM unit as I can't find any markings of "Nabco" or "Made in Japan" anywhere.

 

[Forced4dur]

Well, finally an update, but not in a good way.

Replaced the master and slave with OEM and after bleeding has about the same pressure as before.



This coming Sunday I'm having a friend/mechanic drop the trans and see if it might be the pivot ball, fork, or TOB. Hopefully this issue gets taken care of! It makes me sad seeing my G sit in the driveway for such a long time in the middle of being tuned.

Will give an update when things get checked out guys!

 

[Jacolu3]

Oh man that sucks. I was pretty convinced bleeding it would do the trick because I had the same issue a while back with one of my Hondas. Well hopefully it gets figured out.
Good luck

 

[Forced4dur]

I was hoping! Especially because the MC was in fact not OEM. Going to try adjusting/bleeding once more before pulling the trans.

With my current luck nothing will be wrong there, and my pedal assembly gave out all at once. Haha.

It's just so strange I don't have pedal pressure...but that's also why I'm leaning towards a pivot ball or broken fork. I'd assume if it was a broken spring in the clutch disc or broken fingers it would feel like pressing against a brick wall at a certain point.