Brake bleeding 2 days in no results

Hello All!

I am at the end of 4 weeks of modding my 81Maxim650 (yes my name name says 82, after buying parts from Chacal I have found its an 81), I replaced the upper brake line and front brake pads as I went to 15" bars. Now for the life of me I cannot get pressure to build.

1. I have pumped over and over, but nothing.
2. If i cover the MC outlet i have pressure.
3. I do have fluid comming out of the bleed screw at the caliper.
4. If i go very slow with the lever it feels like it has resistance, if i go normal grab its like butter.
5. I do not have the "Old Faithful" effect, nothing sprays out of the MC with the cover off. Now am I to understand, the "old faithful" is just what it says, fluid under pressure flying out of MC? If so, i do not have that occuring.
6. I have bought the "one man brake bleeder" today, but the instructions dont say if i should prefill the container, or leave it dry? So which way is it?
7. I have been doing the pump 10 times, hold lever to bar, loosen bleed screw, fluid stops, tighten bleed screw, repeat. Is this correct?

Any help would be great as this project should have been done by now and its 90 in NH this week (not normal this late is season and really looking to ride with the new setup )

Thank you in advance!!!

 

Air can build up at the banjo fitting on the master cylinder (MC). while squeezing brake lever, crack open banjo fitting on MC and see if air burps out.

I use the Vac pump dry and have no problems.

As for the hand pump should only take a few minutes to get fluid flowing to the cup in the vacum pump.

Did you check the adjuster screw on the brake lever to make sure its contacting the MC. I had one come loose while doing some work and thought the MC was shot but on further inspection found the contact screw had backed out.

 

i have found MC masters just dont push enough volume for the relatively large diameter rubber lines, and the air bubbles dont get pushed down as effectively. you can run 3 qts. through and still have air. a power bleeder does a good job of "rushing" fluid through the lines and pulling the bubbles down and out.

 

They are tough to bleed if the MC isn't letting the plunger all the way back and even if it's working 100% they can still be a pain to bleed.

As the others have said, a vacuum bleeder is the way to go.
Similar to http://www.sears.com/shc/s/p_10153_1260 ... ckType=G12

 

The "MityVac" gets my vote for bleeding brakes. I've had mine for a few years now and can't think of bleeding an empty system without it. I also use it to check sensors on autos. Many uses.

D

 

I thought the sequence was: -open the bleeder-squeeze the lever and hold it-close the bleeder-release the lever-repeat...

I am not familiar with the pump 10 times method.

It takes a long time.

In case you're considering it, I don't recommend those speed bleeders. Didn't work for me. Maybe others have had better luck with them.

edit: I had a hell of a time bleeding the stock lines. After switching to stainless, it went a lot better. Backs up what Zookie said.

 

Thanks for the help!!

I tried using a syphon and pulling fluid through the system from the caliper bleed screw, about 5-6 times. This draind the MC, I stopped at 1/2 way to avoid pulling air, and everything is clean as a whistle. I then refilled the MC and went back to bleeding. I got to the point where I now have clean brake fluid out of the bleed screw, no air, but nothing in the way of a stiffening brake lever. Look like im off to Chacal for a MC rebuild kit!!

Thanks again for the assistance!!

-Mb

 

Try this before ordering new parts:

Open the top on the MC and fill reservoir... with bleeder valve closed, pull brake lever towards handle and tie off for 24 hours. Don't worry if the brake lever is in contact with the handle. The main thing is to have the brake fluid under pressure. Tiny bubbles will slowly release out the MC reservoir. After 24 hours, untie brake lever and check brake function. I have had excellent results getting the last bit of air out with this method.

 

Ok ski84 you got it! I will give it a go tonight when I get outta work and post my results Thursday morning.

Thanks alot!!!

 

My favourite subject

Did you re-use the old copper washers? No harm in doing it but sometimes some are past it to re-use. Look carefully at all the washers while you pump the MC, sometimes fluid sorta weeps past without being noticed (or gets disguised in the buckets of water we wash it off with). Sometimes you can even hear it.

PS. Just noticed you posted 'upper brake line'. That means you're still using the junction, right? If so, remove the junction from the lower triple clamp and move it about while you're bleeding (the brakes, that is). Air bubbles love to stay in there. Good luck!

 

Yep, I did use the original copper o-rings, and thats a good possiblity. They looked OK, but maybe they arent. Wonder if the local bike shop can support replacements?

I have wondered about that junction... I dont like it at all lol. It does look like an air bubble palace.
Whats it purpose? Could I just run 1 cable from top to caliper and eliminate it?

Thanks for the info classicracing!

 

Wait a sec...

ski84 you said bleeder valves.. Theses another one besides the caliper??? Where???

Oh boy... Am I going to be laughing!!

 

I forgot the 650 has a single caliper...sorry, I should have said bleeder valve. Procedure still applies with single bleeder valve.

 

Whew!! I was gonna say man I have been all over this thing lol!!

 

You tried using a siphon and "pulling" the fluid through the system? That should do the trick. These systems are real buggers to bleed. You absolutely must use some kind of vacuum device to "pull" the fluid through the system. Whether you use a "mighty vac" or some kind of syringe, you must pull the fluid through the system. You can forget about pumping the fluid through from the brake lever - your two days will turn into two weeks and you still won't have any pressure. Maybe that's an exaggeration - but not much. Keep us posted.

 

Yep, used a syphon tube that my neighbor used to bleed his bike. He said 4 pulls through his and he was set. Mine was no such luck. I am planning on doing the following:

Checking for weeps from orings
Pulling another 4-5 times through the system.
Getting pressure on the handle, leaving the MC open and tying the lever 'ON' for 24 hrs.

Will give you an update on what I find.

Thanks!!

 

Ok so on my 82 750 i re did my brakes. When I went to bleed them they would not build pressure like you said. What I had to do was fill the brake line with fluid first then the cylinder because it wasn't enough pressure to fill the line. After doing that they bleeded fine with the traditional method. So try that.

 

Sounds like it would make sense. Fill the pipe before pressurizing..
Well ok, I will then, fill lines, clean, check for leaks, try to bleed traditional. If no go, slap the "T". Still nothing, vacume, then go with the bungee trick.

You all are awesome! The amount of help has been excellent!

 

1st and foremost, this forum ROCKS!!!!

Big thank you to EVERYONE who helped me with information and tips on bleeding this system. Last night I FINALLY got the system bled and the front brake is perfect.

Upon getting home I walked up to the bike and saw 5 long drop trails on my tank, piants messed up, oh well, it will get repainted. The top banjo bolt o-ring was leaking just enough. (Good call classicracin!) I took off the bolt and cleaned the oring and retightened. Then, I opened the MC, topped it off, and i grabbed the syphon the nieghbor was using the night before. Micro, I agree, syphons are the ONLY way to get these systems moving!

SLOWLY pulling fluid through until the MC was 1/2 empty i stopped, refilled and pulled again. Doing this 4 more times upon removing the syphon, BAM fluid bleeding out nice and smooth. VERY SLOWLY turing the bars to get the MC flat I topped off and watched it bleed for 15 mins steday, no air.

Topped of MC just a bit more, and easily and evenly put on the MC cover. Making sure I was still running smooth for 2-3 mins after the lid was on, I slowly tightened the bleed screw and sure enough my brake is top notch.

Thanks again to everybody, special mention to ski84 who kept me trying instead of ordering parts.

If you want, I can definatley write up an XJ syphon bleed in 30 mins procedure, after this thread I think we all covered all angles of issues to check and came out with a positive result. Let me know, Ill gladly do it!!

Happily rolling today in 90 heat in NH!~!

-Mb

 

where are the pics with the apes installed? I want to see this bike