brake fluid change

What's up fellow biker dudes and dudettes,
I could use a little help with what i thought would be an easy and straight-forward project -- changing my brake fluid for my front brakes. Earlier this week I popped the cap on my front master cylinder only to find nasty brown sludgey brake fluid inside. I immediately removed that nasty fluid from the master cylinder and i also removed the cable at the caliper and pumped the rest of the sludge out of the line. I've got my new Dot-5 H/D fluid in hand and refilled the reservior and buttoned everything back up. I'm now trying to "pump" the line and bleed at the caliper bleeder and I am getting absolutely nothing - no air, no fluid...nada.

I've since pulled front brake line to make sure it's not clogged..and i can pass air through it so that seems ok. I'm running s/s lines by-the-way. What's interesting is that I can actually pull the line off the caliper below and pump the lever and still get nothing...no air, no fluid.

I'm wondering if I've made my fluid change extra difficult due to my emptying the entire line and cylinder before adding new fluid. I didn't expect this to be so tricky... I saw in a separate post a discussion about "reverse bleeding" which sounds interesting. I'm gonna go to an auto part store and look for one of these oil cans that would allow me to pump fluid reverse through the bleeder valve. Any advice out there would be appreciated.

ride on brothers...

-j

Some of that sludge may have gone into the caliper(s). Meaning that you may have to make sure that they are also clean inside. Meanwhile keep on pumping.

Originally Posted by harleyjay

" I've got my new Dot-5 H/D fluid in hand and refilled the reservior and buttoned everything back up. I'm now trying to "pump" the line and bleed at the caliper bleeder and I am getting absolutely nothing - no air, no fluid...nada. "

-j

I think what you have is an air lock. When you put the cap back on it was like putting a straw in a glass of water then putting your thumb over the end. If you lift the straw the water will stay in the straw, remove your thumb and the water runs out. Take off the cap, open the bleeders and gravity will get most all of the air out.When you see solid fluid running out of the bleeders close them down.When doing this be sure the master cylinder does not run empty. Top off the master cylinder and install the cap. Now pump the brake 3-4 pumps and hold it compressed. Open the bleeder***Be carefull the fluid will be under presure and it WILL shoot out in a stream*** Do this 1-3 times for each caliper and you should have a good feel on the brake again. When doing the pump part be sure the master cylinder does not run dry. You can only get 1-2 bleeds out of the master before it goes empty.

Hope this helps

I just did the "reverse bleed" thing on my '03 Fatboy a couple weeks ago to completely change my fluid. It must be easy since I've never bled a brake in my life and it worked just fine. At least it did after I figured out how to coordinate opening and closing the bleed screw with pumping the fluid out of the oil can.

Thanks for the very helpful replies on my posting. I ended up having to take my bike in the shop and had the master cylinder rebuilt. I was able to get pressure in the line but my caliper began to lock up again even w/ the new fluid. At that point I took it in the shop and they had to rebuild my master cylinder.

anyway...i'm just glad to be back on the road again...

vroom...

-j

I seem to be having the same problem you did. I disconnected the line from the master cylinder when i pumped the brake I got no fluid out of the cylinder, I reconnected tried gravity with nothing. Could it be that the cylinder is gone? any help would be appreciated.

Does anyone have any information on DOT 5.5 brake fluid? Has H-D approved it? I read somewhere that it is an improvement in some ways over DOT 5 fluid. Can't remember where I read about it now.

Originally Posted by tbrimer1

Does anyone have any information on DOT 5.5 brake fluid? Has H-D approved it? I read somewhere that it is an improvement in some ways over DOT 5 fluid. Can't remember where I read about it now.

Dot 5 is dyed purple to designate it from the other types. The problem with it was that it changed color to an orange muddy color when it contacted O2 - it oxidized. Silicon was supposed to do away with the problems that the alcohol based Dot 3 has, which absorbs moisture and rusts the inside of the brake system. The 5.5 appears to attempt to solve the colorant oxidation issue.

HD will be very slow to approve this improvement since they will attempt first to claim that they discovered the problem - then they will need to get the Chinese to make some of the new fluid for them and bottle it. Then HD will approve it at THEIR price so us HD customer can buy some....

Bill C.

I wonder if anyone may get some inkling that HD is pi**ing it all away with their attitude and manners. They are run by people with no regard for the bike owner/rider. We are nothing but an open wallet to them!

I did the same thing to my front brakes. The fluid was real dirty so I drained every thing and I run new fluid through until it came out clean. If you get the system completely dry it takes forever to get fluid to come through. Get a brake bleeding kit and hook it to your bleeder valve and start pumping. It may take 10 or 15 minutes to get fluid to come through but it is a lot easier that pumping your brake lever several hundred times. The pump is only about 20 bucks at your local auto store.