The clutch is fluid-driven (hydraulic), and the fluid is brake fluid. The brake reservoir has a tube coming off of the side about 2/3 of the way down. This tube goes to the clutch. The idea is that the clutch can leak enough that it stops working right, but the brakes still have enough fluid to stop the car. After all, the only thing more important than going is stopping.

You have not discovered where the brake fluid goes, yet. But the clutch will fail first. You will need to bleed the clutch to get the air out of the system when you figure out what needs to be done to keep the fluid in the system. The brake calipers and the clutch slave occupy the same position in a block diagram of the respective systems, and they are an opening to the outside world for the brake fluid. You can have a leak from any of the brake pipes/hoses, or the calipers, or the same parts of the clutch system. You should be able to find the wet spot since you are using so much brake fluid so quickly. Indeed, if a caliper is the problem, you should see brake fluid around the inside of a tire, or tires.

 

I checked the inside of all 4 tired and wheels and no sign of fluid.

I did find fluid behind the brake pedal. I removed the plastic around the pedals and found brake fluid dripping from this part. I'm not sure what it is - could someone help? I dont see brake fluid leaking from the reservoir that I can tell without removing it.

Pics below.

 

Brake fluid can easily leak out the rear of the master cylinder into the brake booster.

There is a constant vacuum at the rear of the master cylinder from the booster.

Easy enough to pull the 2 nuts that hold the master cylinder to the booster and pull is forward to check for fluid.

Keep in mind the clutch gets its fluid from the brake fluid reservoir, there is a dam in the reservoir that sacrifices fluid to the clutch in the event the brake fluid gets look.

Having brakes is far more important than a working clutch if you could only choose to have brakes or the clutch.

You might need to replace the brake booster as well, these are failing on the E46 after about 10 years.

http://forum.e46fanatics.com/showthread.php?t=1057387

 

That makes sense. Thanks for the info. My car has idled rough for a while now. I'll look closer and see if I can narrow down this leak.

 

The weeping fluid you see on brake master cylinder pedal boot is a minor concern but that is not your problem. Leave that alone for now.

The clutch master is not integrated with the brake master***8230; its a separate part, located directly behind the clutch pedal. (plainly visible in your photos, to the left of what you've circled). From what I can see in the photos it's perfectly fine.

There is a 99% probability your clutch slave cylinder, or the hose connecting it, has failed. My money in on the cylinder, not the hose. You don't see it leaking because the fluid is accumulating inside the transmission bell housing.

Replace & bleed the clutch slave cylinder. (it's got a bleeder screw, just like your brake pistons) To make the job a little easier, pre-fill it with brake fluid before you install it.

Don't wait on this, accumulating puddles of brake fluid do not play nice with clutch linings.

 

The weeping fluid you see on brake master cylinder pedal boot is a minor concern but that is not your problem. Leave that alone for now.

Not sure this is the advice I would give.

As I stated, brakes are a much higher priority than the clutch.

If you cannot drive the car because of a clutch problem, you do not need brakes, however, if you are in a moving car, I would want brakes over a clutch any day of the week.

The OP clearly has 2 problems, whether or not they are related, who knows, but if the brake fluid was leaking and the clutch fluid part of the brake reservoir went dry, then this may be the cause of the clutch issue?

Brakes are probably the most important safety feature on the car, followed by a close 2nd with steering.

 

Thats the problem I am having now, figuring out if my issue is clutch or brake related. I haven't been able to narrow down where the fluid behind the brake pedal is coming from. I've taken all of the plastic off under the dash so I can see clearly and the clutch master looks fine to me. There has not been any fluid leaking onto the ground when I move the car.

 

The brake master cylinder has brake fluid dripping from it. I can't tell if the leak is coming from that part or above it, that is where my focus is as of now.

 

Like jfoj mentioned, I'm wondering if I have a brake problem and the fluid drains out which stops the clutch. I have not felt any issues with the brakes though, so theres that.

 

I recently had the same problem with my clutch sinking to the floor and it was the master cylinder that was failing, however the fact that you keep having to add Dot4 fluid to it makes me think that it might be something related to the master cylinder. Let us know what you find out when you find out exactly where the leak is coming from. I'd like to know for the future. Good luck

 

I'm going to start with the brake master and go from there. I will keep you all updated. Thank you to all that have replied.

 

Here is what you need to do, fill the fluid reservoir up fully and bleed the clutch, you may be able to do this by yourself gravity bleeding and just allowing the fluid to "flush" out the air, but it is best to have a helper.

Also I do not recall if the E46 clutch slave cylinder was the one with the bleeder screw in the wrong position where you really needed to remove the slave cylinder and flip it upside down to properly bleed it???

Usually the bleeder screw is supposed to be on the high side, not the low side, of the device with fluid being sent to it.

If you are able to bleed the clutch correctly, then I would think air was introduced in the clutch system because of the brake fluid dropping.

 

http://forum.e46fanatics.com/showthread.php?t=950408

Very easy to pull the slave cylinder & check it out***8230; you need to get to it anyway to bleed it.

If it's dry, therm I am wrong and you can move onto the brake master.

 

Ok***8230; we're both just trying to help a fellow E46Fan out here.

I've read many of your posts. You definitely have some good insights, a great depth of knowledge and have taken the time to share that with the community for many years***8230; I'm pretty sure your posts have even helped me out from time to time as well. Apologies if I have offended you.

I'm not at all discounting the leak nor did I say to only address it if it gets worse. Both are problems, both need to be addressed. OP is trying to solve the clutch issue which has rendered the car inoperable and that's what he/she has asked for help with. You have rightly pointed out that the brake master is leaking and we both agree it needs attention, but let's try to fix the problem at hand, which is the clutch. We might also agree that attempting to replace the brake master and booster might well be a job beyond the OPs capability, and best left to a professional. (perhaps I have now also offended the OP) My thinking is we help get the car operational again, and direct the OP immediately to a brake service professional for diagnosis of the master.

We have to think about how that air in the clutch system could have gotten there***8230;. the clutch slave cylinder is mounted at a considerably lower elevation than the brake master***8230;. If you think there is air trapped in the system between the clutch master and slave ( I sure do), then how'd it get there??????

 

burnette,

How'd you make out? Did you find the root of the problem?