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Brake fluid on tire - cylinder need replaced?

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mikeamondo

Jedi Hopeful
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So... I feel I'm being initiated into the Bugeye club quickly! Not on the road yet and brakes have an issue... no worries! I'm ready to start turning wrenches on this little guy!

So when brake fluid pours out of the bottom of the rear wheel drum.... is that most likely a failed cylinder? I haven't pulled the wheel yet. Seller had a box of unused wheel cylinders so maybe that replacement was planned and never done. (and "pours" is pretty accurate... looked like the bleeder valve stream)

If so.... how hard is the job? Any specific advice prior to taking it apart?
Thanks!
Mike

Oh.... and if the reservoir drained before I discovered this.... should the whole system need bled or just that wheel?
 
If it is not the bleeder, a split pipe, or a flex hose, then it will be the wheel cylinder. It's great you already have replacement wheel cylinders. Just make sure they are the right size. Others will have to advise you what bore the BE wheel cylinders are (so you can confirm the new parts you have are correct) and what tricks there are for installing them.

Bleed the entire system, not just the one wheel.
 
So, it might be the bleeder where it connects to the cylinder, I suppose, or the cylinder itself. I guess I'll be able to tell when I pull the drum off. It's certainly coming out of the bottom of the drum... not from up where the line goes in...
 
I assume I'll need to bleed the clutch as well...? I've done brakes plenty of times... never done a clutch. Is the procedure the same? Where is the bleeder valve?
Thanks!
 
There should be an inspection hole in the side of the RH footwell (usually covered with a little plug) for the clutch. Pop the rubber plug off and you can get to the slave for the clutch. It can be pesky to bleed.
 
drooartz said:
There should be an inspection hole in the side of the RH footwell (usually covered with a little plug) for the clutch. Pop the rubber plug off and you can get to the slave for the clutch. It can be pesky to bleed.
Click to expand...

Wow.... 'inspection hole' ..... more like 'torture hole' ... I'm assuming that's why folks take out the psgr seat to make it easier.
So do I absolutely need to bleed that, given the current circumstance... (not certain the reservoir was empty)... or is it more that I MIGHT have to bleed that, and how would I know? Is it just the feel of the clutch pedal? If it has air, in the line, does it go the floor? Sorry to ask stupid questions.... this is day one with the car, and I don't want to spend hours on something if I don't need to.... rather eager to get him on the road for at least a little driving!
 
Those early wheel cylinders have a banjo fitting and the bleeder works off of that brass fitting. It's possible that either of the copper washers were reinstalled incorrectly and not seated. It's possible it just cam loose too. Make sure when you reassemble that you either replace the washers or at least lap then, and they will no longer be flat once used. You'll see what I mean when you go to replace the wheel cylinders. Make sure the bleeder points up at about a 45 degree angle when reassembled. The original rear wheel cylinder is a single piston aluminum body that would be a 7/8" bore. If you have disc brakes, you should use the 3/4" ones instead.

mikeamondo said:
So, it might be the bleeder where it connects to the cylinder, I suppose, or the cylinder itself. I guess I'll be able to tell when I pull the drum off. It's certainly coming out of the bottom of the drum... not from up where the line goes in...
Click to expand...
 
Since you don’t know how old the hoses on the brake lines are for safety sake I would replace them now since your opening the system safety fast !
 
Hoses yes, all three of them. The original LBC Guidelines called for replacing Brake Hoses every 2 years. They swell from the inside and brakes stop working. No external signs. Cheap insurance and part of regular maintenance. And Bleeding is much easier with a helper but failing that a Mity Vac comes in handy. Bleeding clutch can be a bitch. Clutch Fluid recommended is Castrol GT LMA Brake Fluid Dot 4. Do not use Dot 5 Silicone. Castrol changed the name on the bottle recently and it is now known as [h=1]Castrol Advanced Performance DOT 4 Brake Fluid Same stuff new name.[/h]
 
Ok... so the hoses makes sense. Just to clarify.... Do you always bleed the clutch anytime to open the brake system? I know they share the master, but can changing a cylinder in the brake line introduce air to the clutch side of the system? I moved the car last night back into the garage ... was able to shift into reverse and first, no problem. What happens when there is air in the clutch line. I feel I'm short of some basic info on how it all works here... how and when air can get in, and what happens if there is air in the clutch....
 
If you didn't use the clutch with an empty MC, it should be OK. If it won't go into gear, then you probably need to bleed it.
 
It definitely lets me shift into first and reverse and move the car.... so I think I'll focus on the issue at the rear wheel and the hoses and then see how it behaves.... probably will have to wait until this weekend now, tho... bummer.
 
There is a partition inside the reservoir dividing the brake and clutch side. Bleeding one will not effect the other.
 
Gerard said:
There is a partition inside the reservoir dividing the brake and clutch side. Bleeding one will not effect the other.
Click to expand...

Would that also prevent the clutch side from draining (and pulling air into the line) when you suffered a massive leak at one of the wheels? Such as a busted hose / pipe?
 
If you are driving the fluid can slosh from one reservoir to another.
 
I believe the partition is really just there to cut down on sloshing during spirited driving
I don’t believe it’s intended to imply it is two reservoirs
there is only one cap if this is a single circuit master
 
I disagree. The partition will prevent complete draining of the reservoir. For example, if you are bleeding the brakes and you drain the fluid such that you end up sucking more air into that circuit, the clutch side will not drain. Though it may somewhat serve that purpose as well, it's not going to do much in that if the reservoir is full.

lockheedPorts.jpg

SD Bugeye said:
I believe the partition is really just there to cut down on sloshing during spirited driving
I don’t believe it’s intended to imply it is two reservoirs
there is only one cap if this is a single circuit master
Click to expand...
 
I agree with Gerard. Had a clutch failure and the piston pushed out of the slave. Fluid went away fast but I still had brakes to get home on.

Kurt
 
Makes sense... unless you drove hard enough to slosh it out, it should stay in it's specific reservoir. Which would mean I shouldn't have an issue with the clutch... but I should bleed all four wheels, starting at the rear.... guess I have a plan of action! Thanks for all the replies! I'll update this when it's done.
 
That little divider is less then half the capacity of the master cylinder me I would not consider that 1/2’ wall much of a safety. Change all the soft stuff and drive with comfort well as much as you can with single circuit brakes
 
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