What to do with this sludgy brake fluid?

[bigalpha]

1976 DJ.

Almost got it running so now we need to address the brakes. The existing fluid is gelled up. Can we scoop this out, add fluid and flush the remaining stuff through the lines? Will the new fluid act like a solvent with this goop?

 

[Vanimal]

i would change the master for probably $20-30. you're going to go through quite a bit of brake fluid to disolve that crap, if it even works. at that point, the new master may be the same price as any fluids involved.

 

[bigalpha]

i would change the master for probably $20-30. you're going to go through quite a bit of brake fluid to disolve that crap, if it even works. at that point, the new master may be the same price as any fluids involved.

The crud in the MC is actually gelatinous, not solid, so we would be able to clean it all out before adding any fluid.

 

[emptypockets86]

That crud is nasty. Looks like someone added power steering fluid or the wrong type brake fluid in there. I'd replace the mc, flush the ever living hell out of the brake system, and hope it didn't take anything else out. I know you'd rather not replace it, but I doubt the seals in that mc are happy campers.

 

[GSequoia]

Here is what I would do:

Remove all wheel cylinders / calipers.
Purge brake lines with brake cleaner. Blow out with compressed air (assuming no lines have rusting issues, of they do replace them).
Rebuild or replace master cylinder.
Replace wheel cylinders.
Rebuild or replace brake calipers.
Bolt it back together.
Fill with fluid, bleed.
Profit.

When working on the brakes replace all pads and hardware kits. I would also look into replacing the wheel seals.

 

[5-90]

Ew.

If the sludge is that bad, the rubber in the system is probably chewed up. Plan on replacing the master cylinder, wheel cylinders, and soft brake lines - the hardlines can be flushed (I'd also see about getting a long, thin copper wire pushed through - run it one way, fix a pipe cleaner or something to it, pull it back out. EVERYTHING not replaced will want to be scrubbed, don't half-ass this one...)

 

[GSequoia]

Good point Jon, I forgot about the soft lines.

Replace them out of hand, by now they need it.

 

[bigalpha]

Thanks guys. I figured that full replacement is the final product here but I thought I'd check anyways.

 

[O-Gauge Steamer]

Given the state of the system and the, relatively, low cost for the lines, I would replace everything. Any crud left in the system will just start up the process again. How can you be sure you got it all? Even doing a solvent flush has it's issues...

I do not pull punches when it comes to brakes. The '48 CJ I had got everything new. Did not attempt to salvage any of it. IMO, not worth taking the risk...

When I say relatively low cost, it is in comparison to your life and the lives of those that might get hit when the brakes fail.

 

[GrimmJeeper]

Given the state of the system and the, relatively, low cost for the lines, I would replace everything. Any crud left in the system will just start up the process again. How can you be sure you got it all?

exactly. brakes are the one thing you can't half-ass, mess all you want with things that will make the vehicle not GO. Do it right when you're working with what makes it STOP.

 

[bigalpha]

Do it right when you're working with what makes it STOP.

We plan on doing this, thanks. Now to make a shopping list. Probably end up with reman'd parts. Don't really have a good place to rebuild them.

 

[GrimmJeeper]

I can't look it up for a DJ but if its the same as a CJ (likely) a reman unit will run you either 34 or 37 bucks at NAPA, depending on if its front disc or 4 wheel drums.

 

[kastein]

I'm with the rest, rebuild or replace everything.

Brakes and steering are two things I refuse to half-ass, unless it's to get home (and being very careful.) Everything else is negotiable because it means it stops going, but I want to be able to choose not to run into things, and failing that, choose what I'm going to run into... so brakes and steering are not negotiable.

 

[GSequoia]

Not run into things? I'm going to have to raise the :bs:

I'm with the rest, rebuild or replace everything.

Brakes and steering are two things I refuse to half-ass, unless it's to get home (and being very careful.) Everything else is negotiable because it means it stops going, but I want to be able to choose not to run into things, and failing that, choose what I'm going to run into... so brakes and steering are not negotiable.

 

[MoparManiac]

Yeah that's a flat out lie :laugh:

 

[kastein]

Like I said, I prefer to be able to choose what I run into :eyes:

Rocks don't file insurance claims.

 

[bigalpha]

Its got drums on all corners. We are going to replace the master, the wheel cylinders and the soft lines. We almost got it running, too.

The fuel supply line to the fuel pump did not get marked. Any good way to figure which line is supply without dropping the tank?

 

[GSequoia]

There is only one real fuel line, old carb/mechanic pump systems do not typically use a return.anynother lines off the sending unit are vents (possibly to a charcoal canister if so equipped). You can tell vent from supply pretty easily, you can't draw fuel from the vent (unless you're upside down).

 

[bigalpha]

There is only one real fuel line, old carb/mechanic pump systems do not typically use a return.anynother lines off the sending unit are vents (possibly to a charcoal canister if so equipped). You can tell vent from supply pretty easily, you can't draw fuel from the vent (unless you're upside down).

There is a charcoal canister and there are three lines running from the tank. One line runs to the fill tube, so I can rule that one out. The other two go to the top of the tank, though. I was just curious if there was some trick to it before we attempt hooking everything up.

 

[GSequoia]

You could pull the sending unit to see which goes to the sump. Or you could apply suction to the lines to see which one draws fuel (spit, don't swallow).