TheSamba.com :: View topic - brake oil leak. what's wrong with this unit?

Wed Apr 15, 2009 5:32 pm

I've noticed my brake oil level was getting low too soon after fill up. I looked around under the reservoir and found where the leak was happening. Can you tell me what gets wrong with this unit usually so I can check on it? This unit is located right behind the brake pedal as you can see in the pictures. Thanks in advance.

right side view

left side view

Wed Apr 15, 2009 5:36 pm

That's the clutch master cylinder, if it's leaking you replace it.

Wed Apr 15, 2009 5:54 pm

mightyart wrote: That's the clutch master cylinder, if it's leaking you replace it.

no repair?

Wed Apr 15, 2009 5:59 pm

Well if it's leaking out the boot:
http://www.busdepot.com/details.jsp?partnumber=251721401A

Wed Apr 15, 2009 6:02 pm

You can buy a rebuild kit with new o-rings and stuff for about 5 bucks...But you gotta ask yourself one question "do I feel lucky?"

Wed Apr 15, 2009 6:35 pm

tangstadt wrote: You can buy a rebuild kit with new o-rings and stuff for about 5 bucks...But you gotta ask yourself one question "do I feel lucky?"
Waste of time___get a new one. Wonder where the fluid went? Look under your carpet. All that fluid will start to eat the paint on the floor. Have fun cleaning that mess.
It's a right of passage___we have all gone thru it.

Wed Apr 15, 2009 7:05 pm

Bill W wrote: tangstadt wrote: You can buy a rebuild kit with new o-rings and stuff for about 5 bucks...But you gotta ask yourself one question "do I feel lucky?"
Waste of time___get a new one. Wonder where the fluid went? Look under your carpet. All that fluid will start to eat the paint on the floor. Have fun cleaning that mess.
It's a right of passage___we have all gone thru it.
Yeah! I was able to find the leaking area quick because the carpet was wet on the floor.

Wed Apr 15, 2009 9:48 pm

I kitted mine not too long ago, but I can't remember where I found the kits. They were pretty cheap, like $10 or $11 apiece for the master and slave. A little hard to get the piston back in with the new seal, but not impossible. Should last as long as new.

Wed Apr 15, 2009 10:46 pm

It's hard to tell from the pics exactly where the leak is coming from. If it is coming from the boot on top, then get another clutch master cylinder. If it is leaking from that fitting then the fix could be as simple as a new copper washer on either side of that banjo fitting. Clean that area and watch while the clutch pedal is depressed.

Andrew

Thu Apr 16, 2009 9:12 am

Andrew A. Libby wrote: It's hard to tell from the pics exactly where the leak is coming from. If it is coming from the boot on top, then get another clutch master cylinder. If it is leaking from that fitting then the fix could be as simple as a new copper washer on either side of that banjo fitting. Clean that area and watch while the clutch pedal is depressed.

Andrew I checked to see where it s leaking. It doesn't show in the picture but there is a rectangular box thingy above the clear hose. Looks like two bolts are holding it and the bottom bolt is squirting the oil out when I pumped the pedal.

Thu Apr 16, 2009 11:18 am

If I'm not mistaken, then the two left bottom holes simply mount the clutch master. The bottom right is the banjo hyd connection and the top rubber fitting is where the fluid enters from the reservoir. I'm pretty sure the two mounting holes were blind and didn't enter the hyd area at all. If you think the fuel is coming from the bottom of those holes, I would clean it off thoroughly and check again. Perhaps it is leaking from the boot area in a non-visible way and collecting at the bolt.

Andrew

Thu Apr 16, 2009 11:44 am

Is it dripping or squirting? If it is actually squirting around a bolt hole then there is a crack or casting flaw and total replacement would be the only option. Replacements are available through many sources.

Thu Apr 16, 2009 6:41 pm

Andrew A. Libby wrote:

If I'm not mistaken, then the two left bottom holes simply mount the clutch master. The bottom right is the banjo hyd connection and the top rubber fitting is where the fluid enters from the reservoir. I'm pretty sure the two mounting holes were blind and didn't enter the hyd area at all. If you think the fuel is coming from the bottom of those holes, I would clean it off thoroughly and check again. Perhaps it is leaking from the boot area in a non-visible way and collecting at the bolt.

Andrew
You are right
I checked again. It was very hard to see upthere from the pedal area but found the leaking hole on the boot. oil pumped out of a small hole on the boot... what to do now? replace the whole thing?

Thu Apr 16, 2009 6:51 pm

Since you don't seem real familiar with this part of a car, you would probably be way ahead just to order and install a new master cylinder. Swapping them out is very easy, takes little time, and only a few tools.

Thu Apr 16, 2009 6:56 pm

Yes, new clutch master is in order. You'll also want to bleed the system of air after replacement.

Andrew

Thu Apr 16, 2009 9:01 pm

ok! thanks for all your help guys...

Fri Apr 17, 2009 5:09 am

I recommend an OEM stealership unit. Tried an aftermarket one and it failed after 3 months.

Tue Nov 03, 2009 12:49 pm

Looks like I have the same thing going on with my '86 Vanagon, but I am a bit confused. Why would the clutch master cylinder be leaking brake fluid? I checked the reservoir and it was at the min, so I assume the fluid on my carpet is brake fluid. Also, assuming I do need a new clutch master cylinder, should I also go ahead and install a clutch slave cylinder as the busdepot suggests...

"It's been our experience that if your clutch master cylinder has failed, your clutch slave cylinder is not far behind..."

or are they just trying to sell me an extra part?

I'm not very mechanically inclined, but I have been learning alot so far between reading the forums here and looking through my bently manual. Anyway, any help or advice would be greatly appreciated, and in the mean time is it alright to drive? The brakes seem to be working just fine, but if there is a chance the brakes could give out, I would rather keep it parked until I get this fixed.

Thanks!

-Dave

Tue Nov 03, 2009 1:29 pm

Dave, the brakes and clutch share the same resevoir. Should you replace both the clutch master and slave at the same time? I would. They can be a bitch to bleed. Both operate the same amount. If you replace both, you can mark them off your to do list. If you don't mind redoing the clutch bleeding when the slave lays down, then replacing only the defective part is fine.

Tue Nov 03, 2009 1:42 pm

rsxsr,
Thanks for the reply, I suppose I will go ahead and replace both. Have you ever replaced either of these parts? If so, how difficult was the job?