Brake fluid flush any quick tricks

[Dieseler]

I just installed new rotors,calipers and pads when I went to top up the reservoir in the dark with a flashlight shinning on it I noticed a sespool of what looked like a muddy water stir up from the bottom of the reservoir.
It is apparent I have water in my brake fluid so it means I have to flush the entire system any " Quick Flush " tricks out there I can do by myself or is this a two man job.
Pump bleed....pump bleed....pump bleed.....damn I hate set backs.

 

[vasellers]

Speed bleeders, these are replacements for the bleed screw in the calipers/wheel cylinders. They have a valve to prevent sucking air back into them.

Hook a hose to them, run it into a container and make sure the end of the hose will stay at the bottom of the container. Crack open the valve and pump away. Remember to retighten them prior to removing the hose.

 

[dgangle]

You should always bleed your brakes when doing a brake service. Good PM.

I have heard good thing about the speed bleeders. Other options are gravity, vacuum or pressure bleed. Plenty of read on those if you have the inclination....here's one

https://forum.ih8mud.com/40-55-seri...er-motive-would-speed-bleeders-waste-too.html

 

[Dynosoar]

Use a turkey baster or very large syringe to pull all of the old /bad fluid out of the master cylinder reservoir. Then pour new stuff in to bleed out. Speed bleeds are a good thing too. Be sure you start with the left rear (US driver side) then righr rear, left front and finally the right front. If this is a 62 you also have to bleed your LSPV.


Dynosoar

 

[CTFJ]

I have tried numerous one-man bleeders and there is nothing better than just having someone step on the pedal. SO much faster.

If you are stuck on using a one-man bleeder (vacuum type), the biggest problem is getting a TIGHT seal on the bleeder nipple and the vacuum tube. I have had some luck using some heavy/axle grease to seal it. But again, it is not as fast or powerful as someone pushing the pedal.

Get a 10/12 mm flare nut wrench, if you don't already have one! Absolutely essential to not strip the bleeders.

Run a whole bottle on brake fluid through to make sure things are good.

 

[ntsqd]

Oh yes, there is something faster!!! How about a 4.2L vacuum pump?

Takes a bit of prep first though. You need an empty small peanut butter jar, one with a steel lid on it, some 1/8" or 3/16" copper or steel tubing, about 25 feet of appropriate size vacuum hose, and an epoxy like J-B Weld.

Drill two 1/8" holes in the lid, give yourself room to work.
Cut a piece of tube about 2" long and another long enough to reach about 1/2" short of the bottom of the jar while leaving ~1" sticking out of the top.
Scrape off the paint etc. around the holes in the lid.
Scuff up the tubes ~1/2" to each side of where they will pass through the lid.
Epoxy both pieces into the lid on both sides of the lid with about 1" sticking out of the top. Make sure that the long tube doesn't touch the bottom of the jar.

Cut a piece of hose about 2' long and attach it to the long tube. Attach the rest of the hose to the short tube. Use Dynosoar's turkey baster trick (HIGHLY suggest buying your own, borrowed ones seem to raise the ire of SWMBO) to fill the jar to just above the bottom of the long tube. Pour new fluid into the reservoir.
Attach the long hose to a suitable vacuum port on the engine.

Start engine.

Bleed brakes.



A note on this system; at idle the engine will pull air through the bleed screw threads. The only way to stop this from happening is to fill the threads with something. Grease will work, but remember that the rubber used in brake systems really doesn't play well with petro-chemicals. So if you use grease be really, really careful when applying it. The other option, if you can find some, is brake component assembly lube. Apply some of that to the threads and you're golden!

 

[IH8Wood]

My cheapo one-man-solution:
1. crack the bleeder open.
2. attach a piece of hose snugly to the end of the bleeder
3. put the other end of the hose in a large jar.
4. fill the jar with brake fluid so the hose is a couple of inches submerged.
5. Weigh the end of the hose down so it stays submerged.
6. Fill the reservoir, pump the breaks

 

[slcfj62]

Be very careful pumping the brakes if you choose that method of bleeding. When you bleed the brakes, there is no pedal back pressure, and the pedal will go all the way to the floor, which means the master cylinder piston is traveling in parts of the cylinder it doesn't normally go. This normally unused part of the cylinder will most likely have a little rust that will make it rough, especially if your master cylinder is original, or even just a few years old. The rust in the master cylinder walls will shred the O-ring on the piston, and you will be either rebuilding your master cylinder, or replacing it. I know this, because I have done it.

So, I recommend using a vacuum pump method. But if you do decide to do the pump the brakes method, put a block under the brake pedal at it's current maximum travel before you start. That way you won't exceed the normal brake pedal travel while you are pumping. This may take a little longer to bleed the brakes, but will save your master cylinder.

 

[slcfj62]

Oh yes, there is something faster!!! How about a 4.2L vacuum pump?


Cut a piece of hose about 2' long and attach it to the long tube. Attach the rest of the hose to the short tube. Use Dynosoar's turkey baster trick (HIGHLY suggest buying your own, borrowed ones seem to raise the ire of SWMBO) to fill the jar to just above the bottom of the long tube. Pour new fluid into the reservoir.
Attach the long hose to a suitable vacuum port on the engine.

I think I like this idea. I'm a little fuzzy on the 2 inch long hose though. I'm thinking this is the one that you connect to the bleeder valve, but 2 inches seems a little short. Maybe you have a pic of this guy in operation?

And I'm not sure why a little vacuum leak at the bleeder valve threads is a big deal. Since the vacuum is sucking fluid out of the brake lines, it should only make things a little less efficient as it mixes a little air with the fluid being sucked out? Or am I wrong and the leak is enough to stop the brake fluid from being sucked out altogether?

And finally, is the bigness of the capture jar (being larger than the can of brake fluid) how you prevent fluid from being sucked into the engine by the jar filling all the way up?

Would a little valve at the vacuum tube on top of the jar be a good idea, so you can switch off the vacuum between wheels?

I think I'm going to make me one of these.

 

[ntsqd]

2 foot long hose.

Air leaking past the threads isn't a big deal, but it will give you a false negative and could make you think that there is still air in the system.

The small peanut butter jar (I used a Laura Scudders, Chunky thank you very much!) has more volume than the small brake fluid bottle. Which is all that I ever buy. The bigger bottles cost less per oz. of fluid, but sitting on the shelf open (even with the lid on) will pull moisture out of the air and degrade the fluid before it can be used.
I just keep an eye on the fluid level and drain it when it starts to get too full. I've an idea that the engine will let you know that it's sucking brake fluid, but I really don't wish to find out!

Such a valve might be handy. I've not worried about it.

I can take a picture of the unit, but I don't have any of it in use.

BTW X-something on over-stroking the m/c and causing more problems than you solve.

 

[slcfj62]

Doh! I must have read that 10 times and still read 2 inches....and I even had my glasses on. Two feet makes sense. Really a neat idea.

 

[ntsqd]

Credit where due; Using the engine vacuum part of the deal is a friend's idea. He got really tired of pumping his Mity-Vac one day and had an epiphany.

 

[2mbb]

x what-ever on the speed bleeders.

You should change both brake and clutch fluid every two years or so, since brake fluid will adsorb water.

I also remove as much of the old fluid from the reservoir with a turkey baster, wipe the remaining crud from the reservoir, then fill with fresh fluid. the bleeding order should be the farthest wheel from the master cylinder to the closest, but the distance is measured following the brake line path: Left Rear, Right Rear, Left Front, Right Front. If you have a BSPV, then that is bled last.

 

[ntsqd]

Bleeding the LSPV last is curious. The portion being bled, as best as I can tell, is actually part of the front circuit. Assuming that is correct I'd want to bleed it before either front brake.

Could well be that the FSM calls for last, just seems curious is all.

 

[Dieseler]

Heres what I flushed out of the reservoir and the front lines 20 year old vintage fluid.
By the way I bought one of those quick bleed kits it has a check valve so air does not travel back up the hose the only thing is it has a small container which fills up fairly fast but it was a one banana job

 

[sandcruiser]

anyone know the 'correct' size of tubing?
I made some 1/4" .170 tubing work, but it didn't want to fit onto the nipples and I barked my knuckles several times while doing it, and I had to hold it on there while the patient wife did the pedal

3/8" seems very large.

Thoughts?

 

[slcfj62]

Heres what I flushed out of the reservoir and the front lines 20 year old vintage fluid.
By the way I bought one of those quick bleed kits it has a check valve so air does not travel back up the hose the only thing is it has a small container which fills up fairly fast but it was a one banana job

Good grief! That looks like used engine oil. I have never seen brake fluid that dirty. Definitely way overdue.

 

[stocksail]

Good grief! That looks like used engine oil. I have never seen brake fluid that dirty. Definitely way overdue.

Just did mine also with a new MC and it looked the same... with dirt and grit. Failure is imminent in that environment.

 

[orangefj45]

those might all be good ideas but you're not adressing the issue at hand; getting all the old contaminants out of there. to do so, you'll want to remove all the old brake fluid from the res and then remove it from the master. be careful not to crack the hose or plastic nipple. most of the contaminants will get caught between the double/wall setup inside the res. you can clean it out pretty well with a can of brake clean and an air blower. once you have that cleaned up, use a vacuum setup to evacuate all the old fluid from the rest of the system. then fill the master and bench bleed it. now bleed the rest of the system. doing so will flush the majority of the old fluid ( loaded with contaminants ) outta there.
if you don't clean out the res, then the fluid will look the same as the old stuff in no time.......

hth

georg @ valley hybrids

 

[Hertzogg]

I made one of the pressure type bleeders with separate caps for the 60 and the VW Westie. Just don't go over 5'ish PSI (caused a leak on the VW).

An example is here: The DIY $20 brake bleeder