521 brakes issue

[mainer311]

Hainz, it’s amazing that any of your shit ever works.

[Crashtd420]

3 hours ago, banzai510(hainz) said:

As for the claim of bench bleed the master to itsself.??? whats the differece if I just keep refilling it. once the fluid leaves out the bottom of the master who cares.  the air in the lines will, get pushed out along the way till it come out steady with no airbubbles.

You got to hook it back up to the brake line anyways and still have to bleed that air out that might get back in there when screwing the nipple back on.

I never have bench bleed a master brake or clutch.

 

only time I had proplem was i had to put my finger over the hole inside when fluid to get it to suck then it worked.

I thought the same thing but I fought my clutch master to get a pedal ... I did the pump and hold method and used a vacuum, even at the same time... I had no air bubbles either and still no pedal, till I did what I described. Air can get trapped inside the master...

 

[mainer311]

Yeah Hainz, everyone bleeds the masters. I do it before I even hook any lines up to it. 

[thisismatt]

Bench bleeding (or just bleeding it before you hook up the line(s)), keeps you from having to bleed all that air through the system. Especially if you're not moving fast, that air is going to be constantly trying to go back up to the master.

[banzai510(hainz)]

13 hours ago, mainer311 said:

Hainz, it’s amazing that any of your shit ever works.

It seems to work. I dont know how or why other people have proplems

Learned most by watching my Dad doing brakes while holding the Flashlight

[DanielC]

521 brake slave cylinders only have one port for fluid to go in, and any air to get out.   When bleeding the slave cylinder, you have to let the pressure on the fluid push the shoes out against the retracting springs, and then wait for the springs to retract the shoes, and push the slave cylinder  pistons back .  This lets air in the slave cylinder back out the bleeder.

[banzai510(hainz)]

10 hours ago, thisismatt said:

that air is going to be constantly trying to go back up to the master.

thats why I use a long plastic clear line in a bottle and push thru till no bubbles

[Stoffregen Motorsports]

You can bleed the master by simply cracking a line to relieve the pressure. You don't really need to put the tube from the outlet to the reservoir.

 

Vacuum bleeders suck. No pun intended, but they don't work for shit. They help get the fluid moving in a completely dry system and are great for flushing a system, but for final bleed, nothing beats the two person method.

[banzai510(hainz)]

I never had good luck with the vacuum bleeders also

[datzenmike]

Me either but it got the fluid moving into the lines and then I could pump the rest through with my foot.

 

Another thing you could try is loosen off a front bleeder and leave open. This will allow a longer stroke of the master because there is no resistance from the front circuit to hold it back. Once you get the backs bled do the fronts. 

[Stoffregen Motorsports]

12 minutes ago, datzenmike said:

Me either but it got the fluid moving into the lines and then I could pump the rest through with my foot.

 

Another thing you could try is loosen off a front bleeder and leave open. This will allow a longer stroke of the master because there is no resistance from the front circuit to hold it back. Once you get the backs bled do the fronts. 

Yep, leaving one open is also a good idea. Sometimes I leave one bleeder on each end open and then cycle the pedal s-l-o-w-l-y up and down, to make sure the fluid is sucking into the master.

 

Pressure bleeding is another way, but it makes a giant mess.

 

I think the absolute best way to bleed brakes, though I've never tried it, is pressure bleeding from the bottom up. I've heard about it and it makes sense, because bubbles rise.

 

Aside from having the wrong size master, there has to be another problem here somewhere.

[wayno]

On 1/11/2022 at 9:14 AM, thisismatt said:

The only time I had this problem, after adjusting the shoes, was when my master was bad...

 

I also had this issue with a master that was rebuilt, before returning it I took it apart to see why it would not work properly, it was put together wrong when rebuilt, this is when I started to only buy the Centric brand, they are new and not rebuilt, never had anything from Centric not work properly.

[Arifaeth]

On 1/12/2022 at 1:17 PM, wayno said:

OK, I see a possible issue, you need to disconnect the emergency brake cable from the center pull near the cross member, it should have a cotter key or clip, once you disconnect it then adjust the rear brake drums again, then you will have to re-adjust the emergency brake cable to re-connect it.

This cable can be a pain, sometimes one has a hard time putting the drum on when installing new brake pads, the issue is the shoe is held away from the brake cylinder when it should be resting on it because of the tension from the cable.

 

I cannot say for sure this is the issue, but it sort of sounds like it could be the issue if everything else has been dealt with.

That actually sounds alot like what my shoes did when I put em on, they wouldn't sit quite right. I will have to try this