i need to vent....ls1 brake swap struggle

[70chevellemalibu]

Hey guys i need to vent....this struggle wont go away, i have search all of google and forums and they all somewhat say the same thing like bleed the master, use a syring style and backfill the system, keep bleeding, keep bleeding etc.

70 Chevelle with Factory 4 wheel drums.
Converted to LS1 front and rear with alot of help from Tobin.
1" C3 master
Factory 11" booster
Adjustable proportioning valve in the rear circuit.
Factory lines with factory distribution block.

So i started my swap last year:
Phase one:
-front LS1 calipers factory rear drums
-i had 3 bad factory rebuilt master cylinders in a row
-changed out the factory drum distribution to a Disc/drum proportioning valve it caused me "BRAKE" light headaches due to not being centered and it was a pain in the ass i ended up removing it a reinstalling the factory drum distribution block and installed a adjustable proportioning valve in the rear circuit.
-i finally was able to drive the car but it definitely wasnt the braking i thought it was supposed to be but it was effective and reliable.

Phase two: 2017
-install the rear calipers.
-figure out the rear parking brake.
-bleed brakes ---> no pressure horrible.
-i figured out that the factory "front" line was thicker ID line and that it was going to the rear circuit instead of the primary location on the C3 master. So i switched out the lines so that the thicker ID line went to the primary location on the C3 master and put the smaller line on the secondary location on the C3 master.
-leaks in some of the fittings
-leaks fixed
-gravity bleed unsuccessful I tired to do it for a few hours, i then got a vacuum pump to pull fluid and let it suck for about 15 mins and still no fluid.
-my nipples are all in the up position
-there are no visible leaks
-i rebled the master just to make sure.


i am lost, tired of bleeding brakes, tired of this car, tired of smelling like brake fluid.

any help or thoughts are greatly appreciated.

[dhutton]

Wilwood has a nice distribution block with integrated prop valve. I use this often with good results.

Have you asked Tobin?

Don

[70chevellemalibu]

no i feel crappy for constantly emailing Tobin.

[silo84]

Have you replaced all of the flex lines?

I had a similar problem with my Camaro, the rear flex drop line to the axle was plugged and didn't allow any fluid to the rears.

[70chevellemalibu]

All my lines are new. Steel hardlines and Flexcore stainless likes from Kore3

[dhutton]

I'm suspecting that factory drum distribution block. At least that is what I would replace first.

Don

[rickpaw]

.

-my nipples are all in the up position



Sorry, couldn't resist but to laugh at that statement. :)

In seriousness, I went thru similar issue with brand new brakes on a friends 65 mustang. I've tried gravity/vacuum bleed for hours with no success. At the end I went with the tried and trued 2-person bleeding process.

You may have to enlist the help of a 2nd person. Nothing to loose at the moment.

[CapSS92]

I also agree with the two person idea. My kids learned to hate bleeding brakes cause I would make them pump the brakes 15 times over and over lol. Always worked like a champ. :)

[70chevellemalibu]

thanks for all the support, i bought some speed bleeders to help me out when i am in the garage solo.

I will be back in the garage this weekend....wish me luck.

[70chevellemalibu]

okay after a few hours of gravity bleeding, vacuuming the lines and the good old two person method i have brakes......BUT the travel is too far in my opinion.

if the travel is measured between 1 and 6 inches, 6 being at the floor boards and 1 being the pedal not being touched by your foot. The pedal moves freely till 4 and starts braking 4.5-5 which is basically bottomed out and doesnt feel right.

Now i have a deep push rod master cylinder and a deep push rod with my brake booster. I measured my old master cylinder depth vs the new C3 master and its the same depth therefore i dont think it a push rod issue.

What would increase the "pedal" feel to make it seem that the car is braking at the 1 inch mark and gradually increases pressure as the depth increases?

thanks

[F-Body International]

Maybe you just want to build a simple system...get rid of the booster setup and run the brakes manually. Tobin should be able to tell you the proper sizing for a master cylinder.

Just an idea.

[ctcz28]

Wow, what a pain. I don't particularly like bleeding brakes either and always have to do this without help. It sounds like you still don't have the MC properly bled even though you've done it several times. If you have a stepped MC you have to allow 15-30 seconds between strokes when bleeding it or you won't get all the air out. I recently purchased a A-1 Cardone brake bleeding syringe. A couple of strokes in each port and you're done - no more bubbles and the tool is really inexpensive. Years ago I gave up on the other methods of bleeding brakes and bought a Motive power bleeder. It really works great and in my opinion worth every dollar you pay for it. I wouldn't be without one, makes the job an easy one-man task. Is your porportioning valve all the way open when you're bleeding the brakes?

[Rick Dorion]

Plug one circuit (front or rear) at a time to narrow down where the problem is. It's always a pain for me when bleeding a new system. It seems there's always one little cling-on air bubble that makes life miserable. Amaing how a tiny bubble can have such a huge effect.

[dhutton]

I have had great luck using a Phoenix reverse bleeder that I bought on eBay.

Don

[70chevellemalibu]

so i plugged each circuit and the pedal was firm in both front and rear....confusing.

I decided to unplug both circuits and bleed the master cylinder in the car. I did the plugged port method first no air, i then did the open port method using some brake lines with fitting going from the ports into the master reservoirs. I got a good 10-15 air bubbles in the front and a ton of fizz coming from the rear which never really stopped.

I reattached the lines to the calipers and did a rebleed working my way around the car, rear was good! i get to the front pump pump pump (x10) hold, open the bleeder screw no air first pump was a dead pedal again but would get hard on the 2nd or 3rd pump. Eventually it stiffened up but i feel it can be better yet.

any thoughts on why i get a dead pedal on the first pump and it gets hard on the 2nd and 3rd pump......Let me guess more air somewhere right?

[csouth]

I have had great luck using a Phoenix reverse bleeder that I bought on eBay.

Don

Don,

Which version do you have? I've been contemplating a purchase of one.

Chris

[pist0lpete]

This sounds alot like deja vu to me:

https://www.pro-touring.com/threads/116681-Brake-Bleeding-Troubles

I was able to achieve somewhat acceptable travel and feel but like you I think it can be better. The only thing I haven't tried is reverse bleeding. I plan to give that a shot.

[dhutton]

Don,

Which version do you have? I've been contemplating a purchase of one.

Chris

Sorry, just saw this. This is the one I have:

http://www.ebay.com/itm/Phoenix-Systems-2003B-Reverse-Fluid-Injection-Brake-Clutch-Bleeder-/400905891584?hash=item5d57da6f00:g:gPYAAOSwpDdVNVK u

Don

[70chevellemalibu]

update:

I got some air out the master by bleeding it on the car and running a tube from the port fitting back into the reservoir.

Ive driven the car a handful of times and the car does brake, brake pretty decent BUT the pedal is to the floor by the time the car starts to stop. In addition to this if it try to do a brake stand the engine overpowers the brakes and i just drive forward.

There is definitely something not right here......

another bad master cylinder? more air? not enough vacuum to move the booster?

i dont know what to do anymore.

[70chevellemalibu]

after a sleepless night is it possible that because my front brake lines appear to be twisted i have lost flow due to restriction in the line?

[chuckd71]

Wilwood has a nice distribution block with integrated prop valve. I use this often with good results.

Don
This is what I have, used with and without hydroboost. I like it.
I'm guessing you bench bled the master? Sometimes that can be more important than one might expect.

[70chevellemalibu]

well its fixed.

I brought in a fresh set of eyes.....he pressure bleed the system, we manually bleed them and oh man the pedal was rock hard after a few test drives and setting of the prop valve i was smiling ear to ear. In addition we adjusted the brake pedal with the adjustment rod so that the brakes would activate within 1" of dropping the pedal instead of 6-8".

i now have full confidence in the car which is great.

[andrewb70]

Conclusion. Pointed up nipples + two men = rock hard

LMAO

Glad you have it working well!!!

Andrew

[Peter Mc Mahon]

So what was wrong? Just air in the system?

[70chevellemalibu]

air stuck somewhere and moving my pedal made a huge difference.

Even after he bleed the system and before he moved the pedal, it was decent at best better than before. He told me that he could adjust the pedal and that make world of a difference. Basically if the pedal travel is 1 - 10, 1 being at the top and 10 being at the floor the car starts to brake at 2 instead of 8 like it did before.

Doing this i think increases line pressure sooner therefore you start to brake sooner.