I need to find out from those of you who have bled your clutch hydrolics whether you noticed the slave cylinder moving back and forth when pushing the clutch down. I am NOT talking about the required movement of the piston in the cylinder to operate the clutch, I am talking about the entire cylinder moving along with the piece that it is bolted to. It appears to be bolted to metal which is attached to the clutch housing, so I don't see how it could be moving back and forth. I have replaced another master cylinder and I am still having difficulties getting into gear. The clutch is engaging all the way at the floor so it does not want to go into gear. Once in gear, it does not creep, but the engine shakes a little. The slave cylinder appears to be functioning fine with a lot of movement at the piston. But it "rocks" back and forth about half an inch when pumping the clutch. I have bled the hell out of the system and don't think there is any air left in it.

Any info would be great.

Thanks!

 

try pushing the piston into the slave cylinder(keep it in) and then bleed the system. sometimes air gets trapped at the end of the slave cylinder and you can't get it out.





the lil' trick is actually on the bmw instructions.
good luck!

 

I will definitely try that. Thanks...It's weird, I'm on my 3rd master cylinder in about 8 months without excessive driving.

I hope that explains the difficulty getting into gear, but can anyone remember seeing the slave cylinder and the part it is mounted to moving about 1/2 inch either way while pressing the clutch? It seems so odd to me...

 

IMHO the cylinder should not be moving!

Did you say it's bolted to a sheet metal bracket? I'd take that off and look for a crack........

 

Does it seperate from the section of transmission that it is bolted too? The only part that should move is the rod with gaiter on it and the lever coming out of the transmission. The body, the plastic housing with the hose attatched, should be solid.

How did you determine three failed master cylinders?

 

I determined the first one by changing a slave cylinder. It didn't fix it, so I changed the master cylinder. That fixed it. I also was able to determine it by trying to bleed the system. If the master is not working, when you try to bleed it, the fluid in the reservoir goes up and down even with the valve on the slave opened. No fluid would come out of the slave cylinder valve. I have theorized the failure of the master cylinders to an overheating problem I had. My car overheated and at the same time the master cylinder went out. This has happened twice already. I think the added heat under the hood caused the rubber seals in the master cylinder to fail. I have hopefully fixed the overheating problem.

I will definitely check again to see if anything is broken.

 

Are you talking about the clutch master cylinder? I am pretty sure that is inside the cabin, hard to visualiz that over heating. I'm on my fourth slave cylinder now. Mine leak past the piston until they fail. I am looking for an alternative metal cylinder now. I'm not sure if it is the aftermarket clutches or if the part is a POS, but either way I've had enough. I'll either retrofit something from work or build my own. The last failure cost me my second gear synchro.

 

Oh yeah, what were the symptoms that you were having?

 

Instant change in the clutch feel and it instantly would not go into gear. When I checked the coolant, the reservoir was empty from one day to the next. I don't think the actual master cylinder overheated considering that it is attached to the clutch pedal in the cabin, but the fluid getting extremely hot could possibly cause the cylinder to fail. It is the only possible connection I can find. This happened on two separate occasions where the master cylinder failed and the coolant was very low and the car came to temperature twice as fast as usual.

 

I will be looking at the mounting of the slave cylinder tomorrow...hopefully it is a simple fix....

 

How did it go? I am trying to do the same thing. Mine the slave cylinder had a torn boot and was dribbling brake fluid on the ground.

Bleeding with slave compressed, pressure bleeder, gently pumping clutch pedal a few times, no air bubbles in line, then buttoning it up.

After bleeding it several times I got it to the point I can get it in in gear(s) with a little force. I will take it to a nearby shop I have an appointment with tomorrow and have them do it.

https://www.northamericanmotoring.co...slave+cylinder

 

Well, I thought it was the master cylinder since it was the same symptoms as last time, but it wasn't...now I'm on to much worse problems I think. My slave cylinder is pushing the lever at about a 30 deg angle. So it is not getting the full length of movement it is supposed to be getting.

Here is what confuses the hell out of me: I noticed the angle before I removed the slave cylinder. I removed it so that I could compress it all the way and get the remaining air out. After I do that, I bolt it back on and the damned thing is pushing completely straight! I try the clutch and it feels like it is new...exactly the way it should feel. So I put it together and drive around the block, and it is perfect...for about 5 minutes. I got to a bumpy section of road and all the sudden the pedal gets stiff and it is difficult to get it back in gear. It is exactly like it was before I thought it was fixed. So I take everything apart again and see that the slave is pushing at an angle. I will try to get pictures tomorrow. I have tightened down all of the bolts and the slave is no longer moving back and forth.

Has anyone had this problem before? I am assuming that the problem is inside of the clutch housing. Since the slave is connected right., I think the problem is in the angle of the rod that connects the lever that is being pushed by the slave cylinder. There is nothing else that could change the angle...I'm about ready to drive this car off of a cliff...without me being in it...of coarse.

 

After taking mine to a import shop today, they say it is the master cylinder and will have it done tomorrow. I was getting about 1/2 clutch pedal till it became firm. Then still difficult to shift.

I find it odd that both went at the same time?!? We will find out tomorrow.

 

I have heard of one cylinder causing failure in the other, although I don't really understand how that could be possible.

 

Just got my car back. If one or the other fails you are best just replacing both. Each are ~$70.

My slave was visibly leaking, the master showed no indication of failure. I did the work right and was only getting 1/2 clutch pedal.

Only replacing one is subjecting yourself to a huge waste of time when you will likely need to replace both for not much money.

 

Well, it makes sense that they'd both wear out at the same rate, since they both move the same number of times.

My understanding of the OP's problem was that the slave cylinder was moving around, which it should not do...........

 

It moves around kind like it is on a swivel. This is why you need that special tool to compress/bleed it to hold it square. Or make one like this.https://www.northamericanmotoring.co...slave+cylinder

 

im having sorta the same problem.....my pedal was fine with the stock clutch and flywheel and i recently changed my setup to a clutchmaster stg3 and findanza flywheel and now my pedal is super soft. i had no pedal to about half way down and it grabbed on the floor....i gravity bled it and once i cracked the bleeder on the slave alot of fluid just started coming out so i let it go for alil and closed it up.. got some pedal back but not like it was stock even though i have a stronger pressure plate. had my neighbor swing by to pump the pedal while i tried bleeding it and got some more stiffness out the pedal but now its grabbing in the middle and still feels softer than stock

this is getting me so frustrated since i never open the lines when i did the clutch.

 

Hmmmm you would have to refer to a higher power that has done a lot of clutch setups. Like Randy, Chad or some of the other shops.

If bleeding it in the manner you did made it better....it may need to be re-done properly. Which requires a pressure bleeder, and fully compressing the slave cylinder. You will need to make a tool like I did. Pumping the clutch does not work like doing the brakes.

Why you have to do this after your clutch work? I dunno.

 

hey guys....this is UKSUV posting.....you can go through a few slave cylinders and finally get it right. and you dont need a pressure bleeder to do it right either. make sure to fully compress the slave cylinder and keep it there. then manually bleed it like you do your brakes. when u are done and still cant get it into gear dont force it. what u need to do is pump the clutch about 5 times really quick to build pressure and then it should slide into gear. i had this problem for like 3 days of driving it and then all was fine. there is air that gets trapped in there and u just cant get it out. so when u shift gears just be real easy and take the time to pump it 5 or so times...trust me it will work...

 

i will try and look at this post since im never on NAM anymore.....hit me up on the uksuv pm if u have anymore questions. i quicky read over the post but i think i got the jist......as i am doing the same thing on kalbones car at the moment....

 

Here is a simple tool I made to compress the slave whilst bleeding.

 

FREAKING BRILLANT!! My homemade one was more traditional (read) PITA, this would have made my slave bleeding (4times) easier!!

oh and this thread is old..

 

Love that tool! I was really disappointed with the longevity of the plastic slave cylinders. I actually bought one for a '90 Chevy S-10 pickup, (around
$20). I'd used one of these on a TR4 V8 conversion a few years ago. You have to make up your own brake line since it doesn't have the equally crummy snap-fit connector, but you get a proper cast iron cyl (instead of Mr. Leaky) with a proper metal bleed valve (instead of Mr round-off and finally break-off). Just my opinion.

 

A few things! Since I have had a Low Pedal Engagement since the car was new! First, the problem with Compressing the Slave is getting it back on compressed! The piston can leave the cylinder by itself!

What I did from my motorcycle problems is first pressure bleed the slave which will end up with about 1/2 to 1 inch of Pedal Play. I then took an adjustable rod (Snow broom for the car) and adjusted it so that the Pedal was the floor and the bar was against the Steering wheel. Let it sit overnight and slowly release the pedal. This got me to about 1/4 inch which is about 6 MM. This works by compressing the fluid which forces the trapped air in the cylinder back up the tube to the MC.

I am still looking for a smaller piston Cylinder to give me more movement on the clutch stroke. I know this will increase the pressure needed but I simply want to have an Higher engagement point!