Hissing sound at top of clutch while in gear...
 

I've noticed a hissing sound when i'm at the top of the clutch right before i disengage it. It only happens while i am in gear.

Anyone have this problem before? Or know what is causing it?

My setup:
Evoms stage 4 clutch
Aasco lightweight flywheel
GT2 slave conversion

Thanks in advance.

I do too and I'm stock.

Thanks for your input David. Anyone else have experience with this?

No one has had this problem, or heard of it?

Never heard of this before and I have been in many TT's. Weird...

Are there any other symptoms, like the car running strange or where the noise is coming from? any liquid spots on the floor of the garage? is it a constant hiss or does it change pitch with the pedal stroke until it's gone?

The tone does change a bit as i modulate the pedal, but its constant(sound won't die out at this point, unless i engage clutch fully or disengage).

I checked the reservoir up front, and it appears to have leaked. I cleaned up the leak, put a new clamp under it, topped it off with dot4 brake fluid (gt2 slave conversion), and closed it back up.

I have noticed certain signs, but i maybe just paranoid.
-sometimes its a bit hard to take out of gear.
-i feel a small vibration in the clutch pedal.

I'm really not sure if i'm just feeling things, cause i think theres something wrong.

Also the sound comes from the back. I'm assuming near the tranny/motor. (quite hard to listen for)

Thanks for your input

Hmm, I wonder if it is the beginnings of your accumulator/slave/steering pump going? I would at least check all of that, since the pentosin is the source of several burned up 996's. Maybe some of the guys that have had theirs fail will chime in and see if they had similar noises.

good luck with it.

I don't think there is an accumulator in my setup anymore.

I did have a pentosin leak, but it was fixed last week.
https://www.6speedonline.com/forums/...ring-leak.html

I wonder if the power steering still has any connection with the slave setup since i converted to the gt2 slave? Cause technically they run different fluids now.

Anyone with anything they can share, please do...

I heard some where that to test the slave, you pump the clutch pedal 25 times without the car started, and its support to get really stiff if the slave is bad. Any truth to this?

I tried this, and there was no change in stiffness after 25.

The noise you are hearing might be the accumulator, the whole point of pumping, the pedal is to depressurize the clutch hydraulic system so that you dont get hurt when opening the system since your power steering pump runs both your steering and clutch hydraulic. I would check the level of the fluid in the rear resivour and the clutch front resivour and bleed the system by turning the wheel lock to lock and pumping clutch pedal at the same time. If the noise is still there when the system is bleed out, turn off the car and pump pedal 50 times or so to be safe. Then take off the accumulator for the clutch system and place a pocket screw driver inside the hole if it falls into the hole the accumulator is bad and needs replaced. If it stays up your it good. Let me know if thats a help!

Thanks
Ben & Adam

Thanks Ben & Adam, for the continued support.

I don't think i'm running a accumulator anymore. I have the gt2 master/slave conversion done. The clutch and power steering run different fluids now, therefore aren;t connected.

I saw this post:

https://www.6speedonline.com/forums/2013022-post6.html

I'm really starting to think its the TO bearing now. (stage 4 clutch with lwfw; mild chatter)

I wonder what release bearing/ TO bearing should i be replacing it with.

The accumulator should be removed with the GT2 style clutch system he is running. Seems odd the hissing is clutch related, unless it has to do with the load on the engine and the cluch engagement is affecting engine load, thus the noise changes with clutch action.

Thanks for your input John. rep+

The reservoir can make a noise if the valve is going/gone.....that is still in a car even if you have a GT2 evoms clutch mod like me...the power steering still is hooked up.

Jeff

Thanks for chiming in Jeff. Could this noise only appear while the clutch pedal is near release?