Some hydraulic clutch system problems Options

[Coomer]

My car has been driving me nuts lately. For a long time, I've had some troubles shifting into first gear when I'm stopped. Sometimes I'd have to let the clutch pedal out and then push it in again to get into first when stopped. I replaced the slave cylinder, and it made things slightly better.

Now though, the problem is worse. I can't get into first very easily again, most often after the car has warmed up. Also, gear shifts are much more notchy, and I have to pause when shifting from first to second because it's so bad.

Today I adjusted the rod on the master cylinder so that it's pushing the piston as far as it can, but it didn't really make a difference. I also bled the clutch system and it made no difference.

I figure it's probably my master cylinder. I have no leaks anywhere in the system.

My question is, how exactly does a master cylinder fail? Do the rubber seals deteriorate so that fluid can get by the piston as it's pushed in? Does water/contamination get into the system over the time, rusting the cylinder walls so that there's a small gap where fluid can get through? Keep in mind that I have absolutely no leaks anywhere in the sytem.

And if my master cylinder is bad, should I get a cheaper replacement unit from somewhere like Autozone, or should I go for an OEM Toyota one?

Also, my problems get worse as the car warms up. Could the fluid be boiling from slave cylinder or the hard line being close to the header?

Also, do you think a braided stainless steel clutch line would help? Does anyone know if a MR2 or Supra clutch line could fit our cars?

[Bitter]

yes, master cylinders can fail without an external leak. what happens is fluid leaks internally past the cup seals to the wrong side of the piston as you push on it. easy test is to put your foot down with moderate pressure and hold it there, if the pedal slowly sinks down all the way, then you've got a leak internally.

you could rebuild your stock cylinder if the bore looks good, its pretty easy to do once you get it apart it'll make sense and toyota dealer might stock the rebuild kit or be able to order it. if the bore is damaged then you'll want a new cylinder assembly, autozone or whatever is probably just fine. pretty hard to **** up that part

stainless braided line WILL give you a firmer clutch feel, same way the lines work on your brakes.

yes, you can boil the clutch fluid, how near the exhaust is it? if when you grab the line it feels burning hot, good chance your fluid is getting too hot and might be boiling. you can make a heatsheild from some aluminum flashing or heat wrap the exhaust components to reduce the heat transfer.

if theres anything else, i could probably answer or help you find an answer.

[cheeco]

over time the rubber cup seal in the MC wears out and fluid gets past it. put the car in gear and hold the clutch down, if the car wants to stall after a bit and there are no fluid leaks then the MC seal is worn. toyota does sell rebuild kits which run about $30, a new MC is about $100. also the housing is aluminum, so no rust and dont hone it if you do a rebuild.

[Coomer]

What's odd is that if I hold my foot down with moderate pressure and hold it there, it won't slowly sink at all. Also, I can put the car in gear and hold the clutch in for a long time and it won't stall or do anything.

[Bitter]

that is odd, but try a lighter pressure. sometimes its touchy, it'll leak sometimes and not other times, or it really is the heat boiling fluid. make a heat sheild of aluminum flashing or wrap where the heat is coming from.

[Predator]

are you really sure your clutch is your problem?, i sometimes too have a problem shifting to 1st and gotta double clutch just to get it in somewhat smoothly, i'm pretty sure my sync rings is the cause for my problems

[Bitter]

yea, a bad synchro is a possibility. 2 parts RedLine and one part BG SynchroShift. its called the "Scott Grey Mix". he works over at RRE and I've heard good things about that mix curing gears that are hard to get into and smoothing shifts. you can use penzoil syncromesh, i hear its pretty similar to the BG but easier to find. i think the redline to use is MTL.

[Coomer]

I do know that my second gear synchro is going bad, but my gear shifts in all gears recently got much notchier, making me think that it's hydraulic system related.

And next time I drive I'll check to see how hot the line and cylinder get...then probably make a heat shield.

[eggman40]

man you just described the EXACT same problem ive been having with my car for the last couple of months. 1st gear is really hard to get into sometimes once the car is warm. but the rest or the gears go in relatively smooth once the car is moving. I thought it was the clutch fluid so yesterday i replaced it with some dot4 fluid with a higher boiling point. I also added some Lucas additive to the tranny. It helped a little bit but im still having trouble with it. I want to try the stainless line and see it that helps any.

what do you guys think is more likely to be the problem? the slave cylinder is just not pushing the fork far enough? or could it just be the master cylinder like it was stated above. thanks for the help, i would love to solve this problem.

[uberschall]

sa-a-a-ame problem here too. bought it with the car.

i just bled the clutch...it helped a bit, but i'm also going to switch to synthetic gear oil.

[94celicadude]

well i experienced the same problem, adjusted the rod for the pedal, helped when cold, then even replaced the entire clutch master cylinder, and still the same problem, so in the end replaced clutch and its all working correctly now. Not saying that your clutch is bad, but that sounds like the symptoms i had when i needed a new clutch, so if nothing else that could be it. If not good luck.

This post has been edited by 94celicadude: Oct 23, 2006 - 9:57 PM

[eggman40]

i dont think is would be my clutch, its only been used for about 1200 miles, and i havent been hard on it yet.


For the rest of you guys, does your clutch work on occasion? or is it always giving you trouble. On the way home today, my clutch was doing ok for alot longer than usual, but then decided to f up later on. If you guys find a solution, please post as soon as possible. thanks!

[Coomer]

I think I can eliminate the hydraulic clutch system out as the problem. I was playing around with the adjustment for the piston for the master cylinder today, and all it really does for me is change the clutch engagement point. I think that means my hydraulic system is in good shape.

Maybe something broke in my tranny, causing everything to get really notchy overnight.

I'll try changing fluid this weekend maybe, but I doubt it will help much.

[Bitter]

well like i said, if it only happens when hot be sure to isolate the clutch system from sources of heat. also try that trans fluid mix. it may just be your shift cable is out of whack and is missing a little bit?

[eggman40]

Hey guys i had a question, for the twos r us steel braided clutch line, does it only replace the rubber line from the master cylinder to the hard line, or does it replace the entire line from the master to the slave cylinder? Look under transmission for st185 thanks

[Coomer]

I really don't think it's the clutch system though, because I can make the clutch disengage without pressing the pedal too far in if I adjust the piston so that it's pushing more fluid through the system.

And now that I've been driving it for a couple days, I have noticed that it's more notchy all the time...typically I drive the car so slowly when it's cold that I don't really notice the notchiness.

I may try that mix, and I will try making a heat shield...though I kind of doubt it'll solve my problems. I'll see and post back here.

[ra65_22re]

this happened to me as well. i checked everything and double checked but it was my clutch. it had totally fallen apart. well the pressure plate had lost two of the springs but it made my life of going through gears a pain. now its all good. hope you find out the problem coomer

clutch prob

[Delta_Phoenix]

I do know that my second gear synchro is going bad, but my gear shifts in all gears recently got much notchier, making me think that it's hydraulic system related.

And next time I drive I'll check to see how hot the line and cylinder get...then probably make a heat shield.

I'm not sure about your tranny specs, but many manual transmissions do not use synchros in first gear.

[Coomer]

I do know that my second gear synchro is going bad, but my gear shifts in all gears recently got much notchier, making me think that it's hydraulic system related.

And next time I drive I'll check to see how hot the line and cylinder get...then probably make a heat shield.

I'm not sure about your tranny specs, but many manual transmissions do not use synchros in first gear.

C52s do though.

[94celicadude]

i have personally rebuilt a c52, and they DO use synchros on all gears, like i suggested earlier, all those symptoms sound like a faulty clutch, and even though it may feel like its engaging and disengaging properly, it still will make the shifting notchy.