Bleeding brakes grrr!!!!

i have an 82 seca 750.. I have rebuilt master cylinder and calipers already.. I replaced brake lines today and tried bleeding with my mytyvac .. I can’t get any pressure to build up.. the reservoir is full.. i Teflon taped the bleeder screws.. I really don’t know what else to do.. I’m kind of just trying to donit on my own.. rather than pay someone.. any tips would be greatly appreciated

 

What about blowing fluid up from bleeders to master? Or is that dumb

 

do a search this is a very common topic for the 750

 

86 XJ700 Brake Bleed issue Resolved
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XJ750 bleeding brakes!!

Bleeding brakes

This brake is refusing to bleed

bleeding xj750 seca brakes

 

What I do to bleed the system.
1. get a large syringe from a farm store and about a foot of vinyl tubing (you can also use a 2-stroke oil mixing syringe).

2. Cut 6" of tubing and attach that to the end of the syringe. Remove the Syringe plunger. You now have a funnel to fill the master cylinder with.

3. Break loose all four bleed fittings (be sure to put down cat litter or drip pans).

4. Tie the brake lever to the grip.

5. Fill the master cylinder and syringe.

6. Wait overnight (or at least a few hours)

7. You should now see brake fluid coming out. Close the bleeders, and untie the brake lever.

8. Bleed the brakes as normal, starting with the anti-dive bleeders, then the brake caliper bleeders. Remove the funnel.

9. You aren't done yet. There will still be some air in the system. The next step cures that, no matter what method you use to fill and bleed the system.

10. Use a vibratory sander (no sanding pad) and slowly run it along the brake lines, calipers, and distribution block from bottom to top. This will move any remaining air bubbles up into the master cylinder. Tap (or vibrate) the master cylinder to get the air bubbles to come out of the return hole. This process can also be done with a box-end wrench or other similar tool, and tapping the calipers and lines (it just takes longer).

11. Do one final bleed normally, just to be certain that the calipers are fully bled.

12. Use a flashlight to check the fuid level in the master cylinder. It should be below the fill neck. Unfortunately there is no dip-stick or sight glass on this master cylinder, so unless you empty it and measure out the fluid you will need to just eyeball it. If the fluid level is too high the brakes can hydrolock and not release.

 

So I did the gravity method last night.. nothing seemed to have came out of bleeders.. I popped the brake lines and on one side I had fluid the other side I didn’t

 

I get no pressure when using mytyvac .. I Teflon taped bleeders

 

Brake fluid and Teflon tape do not mix suggest you remove the tape.

 

i beg to differ on that one. and if you put it on the threads where your supposed to it won't be in any brake fluid when your done

 

When you rebuilt the master cylinder, were you careful to orient the piston seal correctly?
Did you check the cable adjustment to be sure that the piston is getting a full throw?
Was the return port cleaned?
Was the bore polished?


Moving to the other end of the system:
Were the anti-dive units cleaned?

 

How do I clean anti dive system?

 

And not super sure what you mean by cable adjustment.. I’m sorry I’m a novice trying to make this Bike cool again

 

On the Seca 750 the master cylinder is cable operated, unlike most master cylinders (assuming that you still have the original, hidden master cylinder). There is an adjustment knob on the brake lever, just like there is for the clutch cable on the clutch lever.

The anti-dive is part of fork refurbishment. The brake fluid side of the system can't be fully cleaned without removing the unit from the fork, but you can blast brake system cleaner through the bleeder with the brake line removed to make sure the majority if any gunk is out of it. One of my concerns is that you might have some schmoo that still in the system, and got sucked up into the master cylinder, or otherwise is blocking a line.

doing-the-750-secas-forks-rebuild-now-a-how-to.18730

 

How about the brake cable adjustment? What am I looking for?

 

You'll want to turn the adjusting knob until there is just about 2mm of slack when you pull on the brake lever.

 

adjuster
https://www.partzilla.com/catalog/yamaha/motorcycle/1982/xj750rj/handle-switch-lever

cable
https://www.partzilla.com/catalog/yamaha/motorcycle/1982/xj750rj/handlebar-cable