HELP No fluid to rear brakes

[84dragcutlass]

Okay so I'm stumped. My cutlass is getting finished up but I'm baffled by the last issue. I'm getting a trickle... no no make that a drip of fluid to the rear. The system is new, master cylinder, proportioning valve, blazer calipers, front hard lines, all soft lines, wheel cylinders. I can take the rear line off and hold my thumb over the rear of the proportioning valve when my boy is holding the pedal and I get a drip. Was doing the same thing with the old proportioning valve and master which was the only reason I changed them

 

[pagrunt]

Do you have the tool to replace the pressure warning switch out of the proportioning valve?

https://www.amazon.com/dp/B08N6C1YP3/?tag=gbody-20

 

[84dragcutlass]

Thats a new one on me

 

[motorheadmike]

HELP - Any brake bleeding tricks????

Hey guys. So I had kinda forgotten about the whole front hub/brake growling issue on the cutlass until last week going to the car show. It's quiet until 55mph+ and it's an audible noise and vibration too. Sure enough, I had my master cylinder to prop valve lines reversed as the pic motorheadmike...

gbodyforum.com

 

[CopperNick]

The factory instructions for bleeding the system have a note in them that the proportioning valve has to be released or put into free flow in order to bleed the brakes. There is a button on the one end that has to be depressed to bypass the proportioning function. When you go to use the brakes on the street, it will automatically kick back in when it feels or reads the all up line pressure.



Nick

 

[carnutjw]

Summit version:

Summit Racing SUM-760158 Summit Racing™ Proportioning Valve Tools | Summit Racing

Free Shipping - Summit Racing™ Proportioning Valve Tools with qualifying orders of $99. Shop Brake Proportioning Valve Tools at Summit Racing.

www.summitracing.com

Josh, I had a similar issue earlier this summer:

HELP - Brake Master Cylinder-no rear fluid

Soooo.... confession time. My Cutlass dash brake light came on one day in November 2021, no leaks or fluid loss, so I assumed the four year old "remanufactured" O'Reilly master cylinder (part #10-1738) had taken a crap. Replaced M/C, tried to bleed brakes but had no fluid coming from rear...

gbodyforum.com

Finally replaced the M/C(for the second time) and that fixed it as far as I can tell.

 

[64nailhead]

Verify the lines from the m/c to prop valve are clear and hooked up correctly on terms of locations. Pay close attention to the flares to be sure there is no way they are sealing off the fittings.

Gravity and vacuum bleed. Might take a day or longer.

Lastly, you should be able to blow shop air through the lines from the m/c to a brake bleeder. If your setup won’t let you, then there is your sign.

 

[84dragcutlass]

Thanks for the help guys. Amazing I've been working on Gbody's for close to 20 years now and still learning. I have honestly never had to mess with that button. But now thinking back i have never had a completely new system before or one that was completely dry so that's probably why i haven't ran into the situation. I'm going to order the tool and try again. Hopefully will be able to reset the proportioning valve that thing wasn't cheap.

 

[timo22]

I had the same issue with my Bonneville. I had done a frame off and replaced hard lines , hoses, cylinders and calipers. I had the same issue . I tried the button thing and actually have that centering tool but could not get it to bleed. Then I read where a guy said to drive in reverse and panic stop. I tried that a few times to no avail. Just when I was going to give up, I hung a u turn and had to stop and backup due the the narrow street. When I hit the brake after backing up, I heard a click and my brake light went out and I could bleed the wheel cylinders,


timo22

 

[stuckincincy]

I'll be watching this closely, I'm currentl dealing with the same situation. My prop valve tool just showed up today, still waiting on a couple other parts and I won't be able to try rebleeding until the weekend or early next week.