brakes wont work

I'll probably be trying this in the spring since I don't have a pump!

 

Go to Harbor Freight, in person or online, and buy the mighty vac for $30.

 

Wizard Says to Duct tape the clear vacuum line into a shop vac hose. Start up the shop vac and pull brake fluid through until you see it coming. Thighten your bleeder screw and you got it. Let us know if that works for you.

 

That's one heck of a vacuum pump alright.

 

The information withdrawn by bobe7316

 

thanks guys. man this weather has me down for the moment, i get home and its dark and wet. i will try everones tips asap, and il let you know how it goes for me.
i dont have a high spot in the brake line next to the master.
i did try the trick bill and it didnt work for me
a mighty/shop vac sounds like a mighty good idea mr wizard.

 

ok after some more old fashoned bleeding not to mention my buddy who thinks he knows everyting about bikes gone i think i was able to get it. now it wont start so i cant really verify till i get this electrical prob sorted out!! :evil:

 

Brakes work! The problem was the screw that goes through the lever was installed wrong! The lock nut was on the wrong side. Well at least I kno I got every last bit of air out

 

brakes are better but still dont work. so if im not leaking fluid anywhere and have only a very few tiny little bubbles coming out of the clear tube , the only ting it can be is the master right? cause calipers are solid not leaking, all hoses are tight junction block is blown trough, i have been bleeding teh brakes sence i started this thread, only ting left is master itself cause i did rebuild it. what do you think?

 

can anyone post a pic of there master and hand lever along with the screw from the hand lever to the piston for me?

 

On my 82 XJ650 I also got it with no front brakes. Got bottle, put brake fluid in bottle, attached tubing from bottle to bleed screw. Opened up bleed screw and slowly squeezed. I squeezed till all air bubbles came out of master. Worked perfectly. Another problem I had later was the front brake started to slowly lock up. It turned out to be the little tiny hole in master that would not let fluid back in master.

 

Sure if need be; might take a little while though.

What are you looking for? The relationship between the adjusting screw and the lever?

It will vary from bike to bike and because of personal preference, for instance I have mine adjusted to add some free play to the lever since the rebuild.

Concern:

Those few tiny bubbles mean the system isn't fully bled yet they're what you're trying to get rid of.

This takes a while. My own personal theory is that the rough machining on the inside of the caliper bore tends to trap "microbubbles" in the machining grooves, making the initial bleed a serious PIA.

But if you're still getting bubbles, you're not fully bled yet. Be sure to wrap a turn or two of teflon tape on the bleed screw (don't block the hole) to prevent air from coming from around the threads, producing "false" bubbles.

 

kwiski, i have used your method many a time. i have a one man bleeder i got from autozone which consists of a bottle filled with fluid and you squeeze close valve and repeat. is that what your refering to?
fitz, i will def try the teflon tape cause im tired of brake fluid dripping all over the place this will probably get rid of the little bubbles too. as far as the pic i just want to see where everyone is putting the lock nut.

 

Level the Master Cylinder.
Pull the Cover and Rubber Diaphragm.
Test the Master half-full.
Pull the Brake Lever. Watch for Fluid squirting-up, ... like a fountain.
If the Fluid squirts-up high, ... you need to Service the Master Cylinder.

One Man Bleeders.
A One-man Bleeder works OK for awhile.
Modify the One-man Hose to guarantee a Air-tight fit.

Add 3-Inches of Rubber Windshield Washer Hose to the Vinyl Hose of the Bleeder.
You join the two hoses with a Hose Union.

You have to work to get the Windshield Washer Hose on the Bleeder.
But the tight fit guarantees no air will re-enter the system.

 

hey rick yeah i do get the fountain but only aftersome pumping if i go and just squeeze the handle once i wont have a fountain. so is that good? also i rebuilt the master so unless i got the wrong kit which i doubt cause i compared the new with the old closely i must have a bad master casing am i right?

 

No, but you may still have a plugged port.

In the bottom of the master cylinder are what appear to be two "false drillings."

Look VERY CLOSELY at them; one of them has a teeny tiny hole in the bottom of it. That hole has to be clean clean. I use a single bristle plucked from my HD parts-cleaning brush, and grasped with a pair of hemostats to poke the little hole clean. (Don't operate the lever with the bristle down the hole, the cylinder moving will pinch it.)

One good sized speck of crud and the hole will need poking again.

Some "fountain" is normal, especially if you jam on the lever quickly. (Don't.)

You won't get good brakes until you have no more bubbles coming out the bleeder, pure and simple.

Getting these things completely bled is an exercise in frustration; I've rebuilt more motorcycle front brake systems than I could possibly count, but '80s Yamahas are the biggest PIA to bleed that I have EVER seen. I went through the same BS when I put SS lines on my SR500s, back in the day. I honestly think it's the bloody machining grooves in the caliper bores; I've NEVER had as much of a ring-tailed hassle in over 40 years bleeding brakes as I've had with these, period. Norton, Triumph, BMW, Honda-- all relatively straightforward, bing, bang, bled. Not so '80s Yammies.

Every one was a PIA.

EVENTUALLY you'll get it; I have found that once you get "decent" brakes, a few heat cycles and then a re-bleed will net you some nice fat bubbles. Put a hundred careful miles on and re-bleed; do it again after another 200-300. THEN it will feel like you're grabbing a rock, and you'll need to ADD lever play like I did.

 

A "Swell" ... is Normal.

A show that looks like a miniature "Old Faithful" indicates a problem.

The Fluid in the Cylinder needs to be pushed OUT of the Cylinder by the Front Hydraulic Seal. When that Seal is OK, ... the Brake Fluid gets Pushed and Pressurized in the Lines ... and the amount of Fluid BETWEEN the Front and Rear Seal stays constant ... some getting "Moved" into the Reservoir.

When the FRONT Seal FAILS, ...

Brake Fluid is NOT forced OUT of the Cylinder and down to the Lines.
HYDRAULIC PRESSURE increases BEHIND the Front Seal.
Brake Fluid is FORCED out the Cylinder Replenishment Orifice and "Fountains" up out of the Orifice under pressure.

When you see "Old Faithful" when you grab the Brake Lever.
You NEED a Master Cylinder Rebuild Kit.
All the Kings Horses and all the Kings men, ...
ain't getting you good brake pressure again, ... without the Kit.

 

He rebuilt the M/C already. Unless the bore in the M/C was corroded, pitted, or excessively worn and went unnoticed, the master should be OK.

apsolus, how carefully did you clean/examine the master cylinder when you rebuilt it? How was the bore? It might need to be honed; if you can't get pressure at all and keep getting the geyser Rick describes then you may need to pull the M/C down and look in the bore.

I still think this is simply a case of the "nearly impossible to get the bloody thing bled from empty" syndrome that a whole lot of folks have posted about; it takes a whole lot more doing than one would think.

 

You'll have to look closely at the Bore of your master Cylinder.
It helps to have a Pen Light.

The Bore should be Clean and Not Pitted or Scored.
If you find an accumulation of light-colored matter on the surface of the Bore; it needs to be removed.

Super-heated with a Pencil Flame of a Torch will disintegrate the build-up and turn it into dust.
The foreign matter can be scraped away. Don't damage the Bore.
Tiny pitting can be Honed.

Fabricate a Hone.
Duct Tape the edge of a Sheet of 800 Finishing paper to the surface of a Dowel.
TIGHTLY Roll the Sand Paper around the Dowel.
Add another Sheet if the Roll isn't a TIGHT Fit in the Bore
Be sure the ROTATION is in the Direction that will Rotate the Paper NOT Unwrap it on the Dowel.

Put a 1/2" Wrap around the Tape to keep it tight.

Use WD-40 as a wetting agent and Rotate the TIGHTLY FITTING Rolled-up Sandpaper in the Bore.
Move it In & Out creating a Cross-Hatched Pattern on the Bore until the Pitting is gone.

 

nice advice gentlemen i will def try your trick rich.
bigfitz i hear ya on the bleeding after i check the master again for any abnormalities ill get back on it, thanks again guys