Alright guys I'm at my whits end and need some advice on a brake problem.

I was having problems with the brakes on my wife's Ody so I decided to rebuild the brakes (rear caliper and master cylinder). Before rebuilding the brakes I would have to pump the brakes up before they would work. This to me was an obvious sign the seals in the master cylinder were probably shot. The rear caliper started leaking after I replaced the pads so I decided to rebuild it too.

Now that I have rebuilt the master cylinder (front and rear with kits from Honda), neither the front or rear brakes will pump up at all and there is virtually no resistance when the brake handles are squeezed. I have bled the brakes with a vacuum pump and have drawn two full bottles of brake fluid through the entire system. No bubbles are visible in the vacuum lines so I believe I have all of the air out of the system. With the bleeder screws open and a line attached to the screw, I can pump the brake fluid from the master cylinder into my vacuum catch jar by squeezing the brake levers. But when I close the bleeder screws, there is no resistance. I have checked and there are no visible leaks anywhere in the system.

What the !@#* am I doing wrong? It feels as if there is virtually no fluid in the system.

P.S. Please excuse the swearing!

Thanks, Rand

Had a similar problem once. Seems air got stuck in the brake line. I jacked the rear end as high as possible and let it sit over night. Then I came back and kept working at it. I was told another member had to stand the whole machine up vertically. Keep working at it and you will get it.

Got to be air in the system somewhere or somehow the master cylinder is not primed? I was even thinking of a way to somehow vibrate the master cylinder to get the air out! I was amazed at how much crud was in the system when I flushed it! The fluid was actually brown in color! I have left it alone for the night before I take a sledge hammer to it and really cost myself some more time and money!

Try pushing fluid in the opposite direction from the bleed screw back to the reservoir

Tried pushing the fluid back through the bleed screw with no luck. Worked on the front for about 2 hours and it still will not pump up. Once I get rid of the 66 VW in my garage I will have room to try to stand it in end or something. Right now space is limited and I am working on it on the trailer.

I take it you used a hand vac to pull fluid thu lines and remove air from system. If this was done and you have no pressure something is wrong in the rebuild of the master cylinder( pressure pump).One way to tell for sure is to attach hand vac to bleeder put some .10 vac pressure on it and open bleed screw slightlyto see if fluid is pulled then tighten the bledder screw back in until the .10 of vac is held. Them add pressure from master cylinder by working handle and see the handle pressure increases and vac is lost. If not its for sure your master rebuild.

Heres a pic.

Forgot to ask if you used any solvents during rebuild. It will damage new seals. If used to clean you must reclean with brake cleaner and use brake fluid to assemble.

No cleaners used in the install of the cups on the master cylinder rebuild and brake fluid was used to lubricate the seals before installation. As you mentioned, solvents will harden the cups and they will not seal properly. I pulled the master cylinder off again to check to see if some idiot (me) put the cups on upside down or something. Everything is installed correctly and lubed with brake fluid. On the bench if I seal the discharge end of the master cylinder and depress the piston it pressurizes.

Not sure if I understand what you mean when you are saying to pump the brakes with the bleeder screw closed and watch the vacuum unit for a pressure increase. Unless I missed something (probably), I'm not going to see any pressure increase on the vacuum unit when I pump the brake handle if the bleeder screw is closed because it is attached on the end of a closed bleeder screw. Where are you attaching the vacuum unit once the bleeder screw is closed?

I can actually pump fluid through the system with ease if I leave the bleeder screw open and pump the brake handle. Something else I find weird is that with a vacuum of 20 on the system and the bleed screw open almost 1/2 turn, it doesn't draw fluid through the lines easily but if I pump the handle it flows through like a fire hose!

Look like I'am the idot. I sometimes do not read right. I read and thought it had fluid thu system and no pressure at handle or pressure with bypass.

To clear up bleed screw thing: After most air bubbles are removed using .20 of vac pulling fluid thu. I then tighten the bleed screw 100% to cut off fluid then pump up to .10 and crack bleed screw untill vac starts to drop then every so slightly tighten untill system hold .05 with out compleetly tighting the bleed screw and then pump handle. Under pressure from handle it should pump past loose fitting( bleed screw) and remove and remaing bubbles as well as make sure master cylinder rebuid is good. This will cause the vacum to drop on the guage as fluid from the handle pressure is pushing fluid into the catch cup. An increas in pressure results in loose of vacum and via versa. If the master wil not push past the loose bleed screw the master rebuild is having a bypass situition in it( back wash). Sometimes when I'm loooking for air in the system its the mastercylinder and this is how I found to be the best to fiqure it out. I use this last step in the brake bleed and yearly fluid change to check the static of my brake sytems for the new year.

Does the master cylinder hold pressure once applied ?

Yes: go to break calipier

Does master cylinder have pressure but bleeds off?

Yes: check for air and then see what point if any it back washes useing described method using different vacum strenghts.

Odyssey. 1 Master cylinder for front and rear. Does the fronts work and hold pressure?

Fronts hold and work: check lines from master to calipier.

Lines ok: flush with alchole and refill and check.

Does the master have and hold pressure but the calipier does not work?

Yes: install pressure guage on bleed screw or reworkk rear calipier.

Me: go back and reread post.

Went back and reread. "

Now that I have rebuilt the master cylinder

(front and rear with kits from Honda), neither the front or rear brakes will pump up at all and there is virtually no resistance when the brake handles are squeezed.

I have bled the brakes with a vacuum pump and have drawn two full bottles of brake fluid through the entire system.

No bubbles are visible in the vacuum lines so I believe I have all of the air out of the system.

With the bleeder screws open and a line attached to the screw, I can pump the brake fluid from the master cylinder into my vacuum catch jar by squeezing the brake levers. But when I close the bleeder screws, there is no resistance. I have checked and there are no visible leaks anywhere in the system. "

My conclusion is a bypass in the master. try the vac verses pressure and see if the master can push pat the leak( loose bledder holding vac). Its like having a loos fitting that don't leak untill pressure is added past it's static point of resistance.

Good luck and keep us posted. Last thing is if you take master apart check Id of bore. over sized cups of hone of bore may be in order. Last but not least try diff mastercylinder if it does not pressure up.

Adnoh, I hope you don't feel I'm implying your an idiot because it's probably me! I can't figure out a lousy simple brake system! If my response sounded smug or anything I apologize. I was slightly pissed of at the !@#* braking system when I replied back.

Thanks for the clear up for the brake bleeding tips. Makes sense to me now.

I did manage to get the rear to work just fine after bleeding the system again and adjusting the cable to the master cylinder. The fronts are still not pumping up.

Anyway, after thinking about this for quite some time last evening and realizing the crap that was in my master cylinder and the rear caliper probably reflects the condition of the front wheel cylinders (duh), I am going to buy kits to rebuild them before I proceed any further. I am probably just chasing my own tail right now anyway! I am also going to take your advice and flush the entire system with alcohol before I try this whole thing again after the wheel cylinder rebuilds.

I checked the diameter of the original pistons that were removed from the master cylinder and compared them to the pistons in the rebuild kit and they are only about .003" difference so hopefully there is not that much wear in the master cylinder body. This Odyssey hasn't a lot of use, its just that no one has ever bothered to service the braking system. The brake fluid had the color of a good strong tea and the master cylinder pistons had a build up of a paste like substance around them. The rear caliper was full of crap and the seals started leaking after I changed the pads so part of my front brake problems is probably crap in the system.

Rule #1... Don't be in a hurry to get ready to ride for the weekend!
Rule #2... Never overlook the obvious! If the rear system was full of crap then its a good bet the front is too!


I'm going to go riding this weekend with the family so I will post after I dive back into the problem again.

Thanks again, Rand

Before you go any more on the fronts stop and do this, adjust both adjusters on each wheel until the tire wont turn, you want the brake shoes to be evenly adjusted so tight that the wheel wont turn, then bleed and adjust the cable until you get it where it builds pressure and the lever feels hard, after that then back off the adjusters a few clicks on each wheel at a time until you can now rotate the front tires by hand but you can still feel them dragging slightly, then take the Ody for a ride and try the front brakes if they work ride around with pressure on the front lever dragging the brakes hard, to get the drum brakes to work right you need to wear them in, the shoe needs to match the drum, wear off the high spots, once they are matched good you wont need to adjust them much and they will work perfectly.

Key notes


The brakes will probably NOT bleed correctly until you adjust them tight as I described above, this is the same for the Pilot.

The front brakes will NOT work worth a shit until they are worn in and adjusted properly, once worn in and you get past the initial adjustments they are pretty much maintenance free.

Once you have them working and before you make any final adjustments you want the leading front bake shoe to contact the brake drum first then the rear shoe, meaning back off both rake adjusters slightly rotate the drum, squeeze the brake a few times, rotate the drum listen you will be able to feel when they are just about not dragging then adjust the leading front shoe until it drags slightly more than the rear shoe.

On your first test ride I would adjust them so they drag hard when you try to rotate the wheel, not so tight that the wheels will drag in gravel when your driving but dragging enough if you jump and get the front tires off the ground you will see the tires stop spinning whilst in mid air, what this does is accelerate the break in and makes your life much happier, the wear I am talking about here is not enough to worry about, I replace the front brake shoes on my Pilot 14 years ago, I use my front brakes 99% of the time for stopping, the shoes are still not worn out, worn noticeably but not ready to be changed, so don't worry about letting them drag a little to speed up breaking them in.


Once your past the above step and do the final adjustments you might notice one side adjusted different than the other, that's normal, you might also notice when you rotate the drum it will drag 1/2 a turn then turn free (not drag) that's normal the drum is probably slightly out of round, it will all wear together and work properly over time.

What I have noticed in the past with the brakes I have adjusted for my friends is always the same, they NEVER adjusted them tight enough to start with then had nothing but problems from then on.

Each time you adjust one of the adjusters you need to pull the brake lever 3-4 times before adjusting the next adjuster.

Once broke in the brakes will work perfectly and lock up if you squeeze hard enough on a hard surface, locking up is not a good thing either that's why we have anti lock brakes on cars, just wanted to note their is enough braking power their they will lock up when adjusted right.

Hope this helps.

Ah Ha! This makes sense because as I was trying to bleed the brakes I could hear the wheel cylinders clicking inside the brake drums so I know fluid is moving and expanding the wheel cylinders. I am probably guilty of not having the brakes adjusted properly.

It sounds like if there is no air in the system then there is enough volume of fluid displaced to activate the wheel cylinders completely even if the shoes are not adjusted properly. Throw a little air into the equation, the air will easily compress and not allow brake pad to drum activation.

It sounds like the Ody's master cylinder's fluid displacement volume is so small that there is little to no room for error. Anyone have any idea what the displacement volume is?

Thanks Hoser! I'll try this before I try anything else.

Rand

NO way did I take it as you were calling me an idot. Just tring to help. I can not count the times I was an idot and bone head while wrenching. By chance did you see my post on my rear shocks were I put the tansion spacer on upside down and the rear kiced sidways as I launches off of face of jump. Heck that is why we post up to get other take on it and share. To quote "H" there no dump question except the one you don not ask. It does sometimes make us fell stupid but that's half the fun of it. Ah to learn something new and have fun, that's why I do it. Plus good breaks is a must. All the power in the world is no good without great breaks. IF you stop and think about accerlation and breaking, Breaking is more important. Thank aboout how long it takes to get to full speed from a dead stop and then think about how long it take to decelerate from full speed to to a dead stop. Now that's engineering. Gret breaking account for a 30% increase in power. Plus as you build power the breaking force and tire tracion ratings needs to be taken into account.

Bla bla bla, Glad to here your breaks are coming back to you. Good working breaks equal a safe operating bike.

Well I finally have front and rear brakes! It took a while but I finally got all the air out of the front brake system!

First I adjusted the front brakes as Hoser mentioned but I still couldn't get the master cylinder to pump up after bleeding the system three times with a vacuum pump. I did however find that the front brakes were grossly miss adjusted. Both sides were way too loose!

What I did next was to leave the brakes adjusted tight then put about 20 inched of vacuum on the system and while completely collapsing and holding the brake lever against the steering wheel. I then slightly cracked the bleeder screw and let it almost completely drain the fluid reservoir. It was then that I got a lot of fairly large air bubbles to pass through the system. It was then that the brake lever started to pump up slightly. After doing the same thing to the other side the brake lever would pump up a bit more. I then used the old tried and true method of pump the handle and then crack the bleeder screw with pressure on the brake lever.

Thanks for everyone's help....

Rand

How do they stop have you had a chance to drive and adjust them?

Not yet. Hope to be able to test them this weekend.

no complaints and i am glad it sounds like you got it worked out BUT just for the record:

I am a firm beiever that no air /bleeder pump is ever "needed", i personally have never used one effectively, i believe they work but have never needed one to solve any brake issue i ever had. and i ride alot

I have to agree I have never needed anything but the master cylinder to bleed a brake system, I do have a vac bleeding system I use to bleed brake systems but its used to bleed working systems, I bleed all my brake systems once a year so they have fresh brake fluid in them, if nobody is home to push the petal then I am stuck using the vac setup, I try to avoid using it but sometimes I have to, works great for fluid changing

On the 350 air seems to get trapped easily seems gravity and time works well to make the air move to the high point in the system so it can be removed IE tip the Odyssey up on one end and tap the brake lines and or let set over night.

Not a Oddy but I cannot get the spungy feel out of the front brake on my WR426. Tried everything from cable tie the lever overnight, remove the caliper and elevate over the master cylinder,push fluid back from the slave cylinder nothing works. There must be a pocket within the caliper that holds air?

Ted,try to heat up the caliper,lines, with a hair dryer,sometimes heating up the fluid/air gets it mobile.

One of the things that may have helped was after I tightened the brake shoes against the drums, I left the bleeder screws open on both sides. When I came back a couple of days later to bleed the system, fluid had drained out one side and not the other. This may have left a way for the air to work its way out of the system.

After fighting this issue I would have to agree that while a vacuum pump is great for a system that doesn't have air in it, there is no substitute for the old pump and hold method.

Rand

or a hose is bad


i have had even pull the pads out and pump the piston out near the end, becareful cause it can pop out, then open the bleeder on the caliper while compression the piston

Thanks Barry and Hare I will give that a go as its something I haven`t tried.