Problem Bleeding Brakes

[Rush]

I am having trouble bleeding my brakes. Hopefully, someone has some helpful input.

I'm not able to build any pressure at all and I have NO fluid coming from any brake using a vacuum bleeder. I even used a shop vac to really get things moving. No luck.

Work I've done:
• Rebuilt rear brakes (stock drum brakes)
• Replaced one rear hard line
• Installed new T3 Micro Big Brake kit in the front
• Replaced one hard line in the front
• Fresh DOT4 fluid

More info:
• As far as I can tell, I have no leaking fittings, but it's tough to be certain since I can't get any pressure.
• Using the bleeders on the BMC, I was able to bleed fluid there.
• I loosened the brake line fitting going into the F and R ports on the BMC and fluid came out. I didn't take them off completely because I didn't want a big ol' mess.
• I spent hours tying to bleed the passenger rear brake. I finally moved to the driver's new front caliper. No fluid from there, either.

When I pump the pedal (at any speed) I can watch the fluid go down in the BMC but as soon as I release the pedal the fluid comes back up. If I hold the pedal down, the fluid stays down. I don't know if that's normal; this is the only car I've had where I can see the reservoir while pumping the pedal.
The BMC seems to be making a "pfft, pfft, pfft" sound after several pumps (see video).
https://youtu.be/5AlL3p7lPsg

Since T3 didn't send my brake pads with the brake kit, I made wood "pads" so I can bleed the system. I'm sure that's completely irrelevant, though.



Color me confused.

[gooned]

Try starting with a gravity bleed, just let it sit with bleeders open until they drip.

Bleeding brakes can be a real pain at times…especially on a new system.

[Rush]

I'll give that a whirl. Thanks!

Open to any other info, too!

[datzenmike]

Make sure there is a small amount of pedal play. Push pedal with thumb. It should move with little resistance for a few mm or 1/16" before there is firm resistance.

Loosen parking brake slightly.

Try loosening one rear shoe so there is more travel and fluid transfer. Rapidly pump the brake 2-3 times and hold while the bleeder is opened. Close and release the brake. Repeat.

[Rush]

There is a gap between the pedal & the clevis rod, so that sounds right, at least. My parking brake isn't hooked up because the cables are shot (hoping to replace them soon).
I just replaced the shoes, springs, pins, and wheel cylinders. I also cleaned and put a touch of lithium grease on the adjusters. I've gotten no fluid to any of the 4 corners so I don't think the shoes have moved from their installed position (I can turn the rear wheels by hand).

The front calipers are brand-new, never used Wilwoods, but no fluid there, either.

I was using my hand-operated vacuum pump at the passenger rear but since that was going nowhere after a few hours, I decided to rig up my shop-vac. So, even when using that, I got 0 fluid from the bleeder. Not a drop.

It almost seems like there's a blockage somewhere; but to all 4 lines? That seems like pretty long odds. In the video clip I posted above, you can see the fluid come back into the MC and it makes that weird pfft noise after several pumps. Where in the world would that be coming from without leaking fluid out at that spot?

Can that brake light valve thingie be blocked?
I should mention that I've read every thread about brake issues here before asking & while a couple are somewhat relevant unfortunately, I've not found anything particularly useful for my issue.

[datzenmike]

When the bleeder on the master is opened there is a definite high pressure spurt of fluid when the pedal is depressed????

[Rush]

There is. I’ve vacuum bled it a few times & it flows well.
I took the brake sensor thing out and flushed it with brake cleaner and it flowed just fine. Then I used air and it blew through fine so that’s not plugged as far as I can see.
I also took the bmc out and flushed it and did the same with air. It flows fine, as well. I took the piston out and there is no damage to the seals and the bore looks and feels perfect.

The bmc seems to pump fluid but it just fills back up when I release the pedal. Still no pressure. Is it normal to refill like the video shows? I can’t imagine what the problem is.

I’m still in the garage now fighting with it.

[bertvorgon]

Have you tried...just a thought...of opening ALL bleeders on the brakes ( not the master)

and see if gravity will flow some? It is kinda like you have an air lock, which is compressible, then when releasing the pedal, the compressed air volume just pushes it back!? When you pump, say for the back, do you have a bleeder cracked? OR the front for that matter.

I can hear you pumping quite quickly...that is not the greatest way, slow and steady pumps, that's at least how I do it on a "bled" system.

[Rush]

I haven’t gravity bled yet. I did pump the pedal quickly but i usually do that til i build a little pressure then I go very slowly.

I just got fluid to the passenger front. Is there a trick to Wilwood bleeders? They don’t bleed. I took one upper bleeder completely out & stuck the tubing in the hole then started with the hand vacuum. I got bubbles then solid fluid so I did the other upper bleeder on the same caliper the same way.

The fluid level dropped in the FRONT reservoir when I started moving fluid through that caliper. Doesn’t the front reservoir go with the back brakes? I’m wondering if I’ve got the lines to the bmc on incorrectly. It’d be kinda weird since they’re the stock lines & I don’t remember forcing them into place in the sensor thing but it’s definitely possible!. I’ll take a pic in a second.

[Rush]

[/url]

[bertvorgon]

Front reservoir goes to the back brakes.

Wilwoods will bleed like any other caliper, just more fluid to fill them. I always do the outer side first, then back to inner bleeder. I then go back and re-do, specially for the first time, gets the last of any air and bubbles from the top piston.

I think you need to check the lines!

The sensor is called a: "SHUTTLE valve". if one part of the system gets a leak, the SHUTTLE valve moves over, which then triggers the dash warning light, due to pressure in only one side, NOT EQUAL.

[Rush]

Got it!
I’m trying to find a pic of the line arrangement. There’s a drawing on carpartsmanual.com. I hope it’s right!

[Rush]

I can't find a decent photo of the master/shuttle to tell how everything is arranged. The drawing is different from what little I could find. Would someone be so kind as to grab me a clear photo of their lines (like I posted above)?

[bertvorgon]

I just checked a zillion files....can't believe I do not have a picture of that, so buried on my car. Sorry, if yah get stuck and no one else pops up, I might be able to get to my car tomorrow.

[Rush]

Thanks for trying, Keith. Don't knock yourself out over it. I'll keep digging through the Googles, I'm sure I'll come across something if no one chimes in.
Thanks again!