Clutch acting really weird.... wtf

hey guys the other day i hop into my car and it feels like I got no fluid no clutch just the pedal spring and when i drive it enganges/disengages at the very top, i bleed it, drive it and its back to normal, 3 horus later its like that again, so I bleed it again, again its normal, I drive it again its messed up AGAIN! but theres never air in it, anyway, i stopped bleeding it, and I realized it goes back to normal, so i left it, and then i drive it today adn its messed up again, what the hell is going on im sick of bleeding my clutch ? can a KA tranny slave cylinder be used on an SR ? I have compared them they have different numbers on them, the numbers are both fractions… let me know guys…

Slave Cylinder from a KA - SR is the same

a SOHC vs DOHC KA have different dia pistons (im pretty sure) so when you say the “fractions” are different, that is why but it should only be like a 1/16’’ of an inch difference ?

so would it not fully engage/disengage ? I believe a different diameter would be a higher/lower volume of fluid hence the master needs to be matched in order to compensate for the amoutn of fluid being displaced in a sealed hydraulic system ?

only way the pressure in the line would change is if you got a bigger MC, if you get a slave with a bigger piston dia you are able to push with more area which is enough to make a good improvement.

sort of like getting a brake caliper with a bigger piston, you get more surface area on the rotor to grab to help slow down a bit better. but when you get into something like a Z32 setup which would be a 8pot system vs a 2 pot then pressure/volume does become an issue.

i am goign to run the KA slave hence I am running a KA master… thats my logic…

OK GUYS I REPLACED MY SLAVE AND LINE AND MY MASTER IS NEW AND I FLUSHED THE SYSTEM AND USED A DIFFERENT FLUID AND IT STILL DOES IT OMFG WTF

you already by-passed the proportioning block 3" from the slave cylinder?

yes

it almost seems like this happens when everything inside the tranny heats up after some driving, especially just cruising ont he highway, just driving makes it do that, not nececarilly shifting the gears alot or working the clutch heavily

Is the pressure plate/clutch new?

It sounds almost like your pressure plate is partially collapsed.

But the problem shouldn’t come and go if that’s the case.

It definitely sounds like the system can’t hold pressure.

Did you ever run synthetic brake fluid? It can sometimes corrode rubber parts.

We had a similar problem with an SR/S14 and that was what caused it. It completely fouled the clutch hydraulic system.

I’d try changing the clutch master, not the slave. I might have a spare you can try if you need it.

hey guys i just put in new fluide ‘prestone synthetic’ just to make sure its not the old fluid and it still does it, i really quite dont understnad this… before i change the master, what is it in the clutch master that can be causing this ? let me know… thanks

The only thing int the clutch MC is the piston, a cup seal, and a return spring.
For whatever reason, fluid is possibly bypassing the seal.

i replaced my master in spring of 2005, could it be messed up already ?

hey, i have had the same problem since december and no shop can figure it out,i have changed the slave mc and gotten rid of the clutch damper, if anyone else know how to fix this please help

i am having the same problem too, i took my slave cylinder apart and it seem like everything is good there, i have the MC in my hand right now, and it seems like everything is good there. i just put a new clutch in, with the a new release bearing. could it possible be that the fork that conects onto the release bearing have come off or something? it feels like the it is fine but not really too sure right now?

hey, i have had the same problem since december and no shop can figure it out,i have changed the slave mc and gotten rid of the clutch damper, if anyone else know how to fix this please help

i am having the same problem too, i took my slave cylinder apart and it seem like everything is good there, i have the MC in my hand right now, and it seems like everything is good there. i just put a new clutch in, with the a new release bearing. could it possible be that the fork that conects onto the release bearing have come off or something? it feels like the it is fine but not really too sure right now?

had the same problem with my brothers 240 . he blew his clutch and we repalced it… then the peadal was soft … still worked just felt like crap no spring pressure at all… we put in a new slave cylinder, changed masters and bypassed the perporting valve… nothing helped… no ones been able to figure it out… ive asked many people and know one knows what the hell it is… its a weird problem…

It may be a pilot bearing problem. I read an article about clutch/trannys and it said that pilot bearings are often neglected when doing clutch jobs and when they fail (bearing either breaks or comes out of the crank) it causes weird clutch issues?

has anyone had problems with aftermarket slave cylinders(napa or whatever). I have gone through three in the past year.