jonina

i have a custom swap in my Honda that required a clutch cnc slave cylinder, it was working fine until last night it just lost all the pressure while sitting in my drive way. i replaced the master cylinder and looked for leaks while my bro pumped the pedal but there was no leaks at all. i even soaked all the lines with soap to look for bubbles but nothing the cnc slave cylinder is brand new, there are no visible leaks, anyone have any thoughts/ideas????? please help. it is my daily driver and i need it running asap

s13hero

There has to be a leak somewhere since you're losing pressure did you check the brake lines too?

jonina

no, i have not checked break line. i did not know they were connected to the clutch lines. ill check right now thanks

jonina

i actual do not think it has anything to do with the brakes. there is only one line from the master cylinder to the container then to the slave cylinder :/

s13hero

Sorry, I can't read. I assumed brake master despite everything saying clutch and slave

jonina

i think there is a leak somewhere but what would be the BEST way to find it? i have never herd of anyone using food coloring but will that work? lol

s13hero

IDK about food coloring but I know there are dyes that claim they are for break fluid, if you google for break fluid leak dye you should find something, I've never personally used it myself though. How do you know the slave cylinder is losing pressure?

jonina

i bleed my clutch and it doesn't get stiff like it supposed to and in a while it just gives out and the pedal hits the floor with little pressure

jonina

the pedal has alittle pressure right now but only at the last 5 inches before it hits the floor

JDM-sol 89

Sounds like you just need to keep bleading it. You would be surprised to see how many pump cycles you have to perform to get the clutch pedal back.

What custom swap do you have requiring a special slave cylinder?

jonina

f2d. need a pull slave cylinder. i ran out of a whole bottle of brake fluid already. ill go buy another and try it again :/ OOOH! i forgot to mention, i used that white tape on the threads but the fluid dissolved it. im going to autozone right now and try something different for the threads. i read i need some type of grease. be back in a bit. THaNKS

s13hero

AFAIK you don't need any kind of tape for the fittings they should seal without it, as suggested earlier in the thread I'd keep bleeding. The pedal going to the floor doesn't necessarily indicate a leak nor does it necessarily indicate a bad slave cylinder at this point.

JDM-sol 89

I mean if the resivoir is taking the fluid and its not leaking ANYWHERE then you should be good.

Before you go and start on this new bottle of fluid, go ahead and double check everything. I usually run my hands along all of the fluid lines to feel for anything wet or out of the ordinary. Also, get a flash light and check up under your dash where your push-rod connects to your pedal assembly. If your master cylinder was leaking it would be leaking on the inside and down the fire wall.

jonina

i checked for leaks about 10 times already. everywhere. i even replaced the master cylinder because it was leaking from there but that was last week and it worked after that until three nights ago when the pressure gave out. i went to homedepo today and bought some sealant and put some on all the threads and put everything together again. now im waiting till tomarrow morning for it to dry up 100%

Axatax

Did you check for any leaks in the foot well where the CMC enters the cabin (and inside the rubber boot)?

jonina

yes. i checked VERYWHERE. i figured it out though. i guess the leak was not big enough for brake fluid to leak but it was big enough to suck in air when i tried to bleed it. i removed the cnc slave cylinder and took it apart and filled ALL the threads with some paste sealant that i bought at home depo and it works fine now hopeully it is still good tomarrow lol this a pic of the cnc THANKS FOR YOUR HELP GUYS!