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Brake Bleeding with SpeedBleeders; WTH

Bundy

Bronco Guru
Joined
Jan 10, 2009
Messages
2,045
I don't know what I am doing wrong but I think something ain't right.

I replaced the M/C (which I bench bled), all the front lines for my 77' front end (vacuum boost) and left the rear lines, but they had run dry from the previous M/C. I also invested in the nifty Speedbleeders so I could bleed it myself.

I bled in the order everyone says, furthest away from the M/C to the closest, and after passing a two quarts of brake fluid I still am getting bubbles in the rear and front. There are no leaks anywhere and I can see that the bubbles are coming out of the speedbleeders and because they are supposed to be a "one way valve" I am assuming they are not drawing in the air.

Is it possible that I have that much air in the lines (new lines in the front, dry in the rear) that I need to run that much fluid through?

I also saw a thread about the rear proportioning valve- pretty certain it's not stock but do I need to do something with that before I bleed the system?
 

richparsonsx

Jr. Member
Joined
Feb 27, 2011
Messages
149
Stock there is no rear prop valve on my truck. I would wonder if all of your fittings are tight? Check your H Block. Sounds like WAY too much air pulling through for your system to be sealed up tight.
 
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Bundy

Bundy

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Joined
Jan 10, 2009
Messages
2,045
I never touched the H block though and I had brakes before. I double checked all the fitting connections... I did have to use adapters to go from the 3/16" brake line to the 7/16" stock rubber outer houses and they leaked at first but I tightened the adapter down VERY tight against the rubber outer and then made sure the 3/16" line was more than secured into the adapter.

I would think if it were pulling that much air I would have that big of a leak... but I guess not! LOL
 

73azbronco

Contributor
Bronco Guru
Joined
Nov 11, 2007
Messages
7,796
speed bleeders are great but can get clogged and let air back in. That would happen if the fluid is dirty. In any event, slow operation of brake pedal helps keep air from being drawn back into line.

My bet is you still have air in MC.
 
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Bundy

Bundy

Bronco Guru
Joined
Jan 10, 2009
Messages
2,045
Damn, I bench bled that hooker for at least 20 minutes, just as it said to so I hope it's not the M/C.

I didn't replace the rod that came with the M/C (guessing that is what hits M/C piston) because they are the same M/C but would it be possible it's not pushing the piston far enough to build up sufficient pressure to push the air out?
 

broncodriver99

Bronco Guru
Joined
Jan 27, 2008
Messages
4,780
Loc.
Glen Allen, VA
Damn, I bench bled that hooker for at least 20 minutes, just as it said to so I hope it's not the M/C.

Well there's your problem. You were supposed to bench bleed the MC not the hooker. ;D

My old '72 was the same way. I ended up getting one of those nifty one man brake bleeders with the vacuum pump. I think I ended up running 2-3 quarts of fluid through. Is the fluid coming out clean now? Sometimes you have to let them sit for a day and let gravity do a little work.
 

Pokey71

Bronco Guru
Joined
Feb 24, 2007
Messages
1,010
I agree. sounds like there was some crap in the lines.

I love the speed bleeders.
 
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Bundy

Bundy

Bronco Guru
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Jan 10, 2009
Messages
2,045
The old fluid was pretty nasty, but it was coming out clear on all ends (referring to the hooker again :D)... maybe gravity and some more bleeding will do the trick. I'm gonna try again when I get home.


The bleeders work awesome- I would be much more pissed off if I had to open and close the bleeder screw everytime.
 

rtj731

Sr. Member
Joined
Aug 20, 2007
Messages
407
For whats it's worth, I had issues bleeding mine and installed the speedbleeders, still had air.

I took it to a local tire shop $35 total to have them bleed the system with their equipment.
Well worth the $$ and hassle free.

Ps while bleeding it myself I found out that just a small turn of the speedbleeders was needed any more and air was able to pass back thru
 
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Bundy

Bundy

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Jan 10, 2009
Messages
2,045
For whats it's worth, I had issues bleeding mine and installed the speedbleeders, still had air.

I took it to a local tire shop $35 total to have them bleed the system with their equipment.
Well worth the $$ and hassle free.

Ps while bleeding it myself I found out that just a small turn of the speedbleeders was needed any more and air was able to pass back thru

I thought about that- they didn't come with direction but when I googled it said 1/4-1/2 turn... I was going 1/2 turns so maybe this time I'll try only going 1/4 turns and see if that helps.

I would take it to a shop, if only it were driveable (no shocks or brakes). I really wanted the satisfaction of figuring out a fundamental braking system but it turns out I suck at this :D
 

garberz

Bronco Influencer
Joined
Jun 24, 2007
Messages
6,856
Loc.
Conejo Valley, Ca.
Ryan, do you have the stock 76-77 proportioning valve? If you do, you'll need to take off the small cap on the end of it and pull out and hold the spring loaded rod, while your bleeding the fronts. For some reason, that valve will hold air if you don't. ;)
Mark
 

half cab

Contributor
Guru Bronco
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Dec 8, 2010
Messages
16,306
You said the rear lines were dry and you put new ones on the front right?Well I let mine set for several yrs and had to do same thing your doin MC to rear lines with pump bleeder and it took like 3 bottles of fluid before I got all the air out.I was starting to wander about it though and then air all worked out and now have better brakes than I can ever remember on it.Don't give up on that speed bleeder just yet.I believe you'll get it.

Gene
 
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Bundy

Bundy

Bronco Guru
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Jan 10, 2009
Messages
2,045
Ryan, do you have the stock 76-77 proportioning valve? If you do, you'll need to take off the small cap on the end of it and pull out and hold the spring loaded rod, while your bleeding the fronts. For some reason, that valve will hold air if you don't. ;)
Mark

I don't think it's stock- I googled pics of the 77-76 valve and they didn't look the same. The one I have is blue- will have to snap a pic of it when I get home today.



You said the rear lines were dry and you put new ones on the front right?Well I let mine set for several yrs and had to do same thing your doin MC to rear lines with pump bleeder and it took like 3 bottles of fluid before I got all the air out.I was starting to wander about it though and then air all worked out and now have better brakes than I can ever remember on it.Don't give up on that speed bleeder just yet.I believe you'll get it.

Gene

Thanks Gene- I bled em' for a good hour yesterday, twice over the whole system and there was STILL AIR in the system. Pissed me off! Either the speedbleeders don't work (brand new) or something with the proportioning valve isn't working or I need to mess with the valve to allow it to bleed properly (as Mark noted)
 

Skiddy

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Joined
Oct 8, 2003
Messages
11,557
but i bet your leg is getting stronger;D hope you get it figured out, i can't think of anything else either?:?
 
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Bundy

Bundy

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Jan 10, 2009
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2,045
but i bet your leg is getting stronger;D hope you get it figured out, i can't think of anything else either?:?

You got that right Skiddy!

On top of that, my dog is really pissed off because he watched me jump in and out of the bronco about 50 times and was wondering if were actually gonna go anywhere or not- I'm sure I'll come home to a dookie on the rug LOL
 
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Bundy

Bundy

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Jan 10, 2009
Messages
2,045
This is an H-block right? not a proportioning valve? Would this POS be holding air and giving me problems? I don't see it's point besides providing a union between the lines??

Is the cap in the middle for the brake warning light?
 

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Bundy

Bundy

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2,045
Alright, I found this tech article from Tom's that says
The H-block shown is the most common configuration on drum brake Broncos and is always confused with a proportioning valve. This IS NOT a proportioning valve. It's only a junction for the brake lines, which also serves as a brake warning light switch. It wasn't until 1976-77 that Broncos came stock with proportioning valves.

So all I need is an adapter and I can get ride of that thing?? Would it be impeding my ability to bleed the system??
 

Rox Crusher

Bronco Guru
Joined
Dec 13, 2008
Messages
2,772
I have a 77 so I will go look at my set up to compare it to the pic you provided above.

I don't know why they went to a proportioning valve in 76 / 77 but I bet they did it for a good reason (I believe 76 is when vacuum assist brakes were first made available?).

You say you have a 77 front end with vacuum assist brakes, but what year is your EB ? In other words, did you swap a 77 into an earlier model EB ? If so, maybe it still has an H-block but needs a proportioning valve.

Having said all that, I don't think this is the problem.

I had some bleeding ars aches when I converted to astro boost and the advice I got was to drive it for 500 miles and then bleed again to get the remaining air out. I don't know why or how but it worked for me.
 

dbevans2249

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Joined
Sep 21, 2003
Messages
610
Loc.
Buena Park, Ca.
Speed bleeders are good and I use them but they dont always work as advertised for me. I think that you may have more luck if you open the bleeders just barely enough to let fluid out.
 
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Bundy

Bundy

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Jan 10, 2009
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2,045
I have a 68' that the PO's PO put a 77' D44 w/discs and brake booster but there is no proportioning valve, only the old H-block from the drum setup. they just capped the H-block and ran new lines for the front. If that isn't giving me problems bleeding, I am not gonna eff with it.

Maybe I am opening the speedbleeders too far, but on my last effort I even had the bottom of the bleeder's line submerged in a bottle of fluid, was careful to not let any air back in.

Basically, if it isn't the H-block and I don't need a proportioning valve I'm finding a shop with the pressure bleeder LOL
 
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