Ok so I just got this truck on a trade.
84' Ram W150 w/ a 318
I got the truck running and did all the general tune up stuff.
The guy told me that just the one rear brake was bad and it had new lines.

However I found that all the rear lines where shot and leaking as well as bad shoes. So I replaced everything from under the driver door all the way back. New Lines, brake hose, more lines, wheel cylinder, springs, shoes, drums.

I bled the brakes and still had no stiffness in the pedal.
So I decided to replace the calipers and pads.
Replaces those and tried to bleed again.

Now this is where I am getting no where.
I cant seem to get any fluid to come out of the brakes lines while I'm bleeding the calipers.

Am I missing something?

I am about to go and replace all the front brakes lines from the calipers to the control check, the brake control valve check, lines from the control check to the master cyl, and the master cyl.

I am wondering without spending another entire day and more cash under the hood, if I am just missing something.

Any help would be great.

PS I have tried vacuum bleeding the brakes too, I get no fluid on the front calipers and all the fluid I want out of the rear wheel cylinder bleeder valves.

Thanks!!

 

Have you checked at the master cylinder?

 

If you have a metal coat hangar, you can snake it down the lines to see if they're clogged. just a thought.

 

Only the front of the master, the second brake line is old and frozen into the master. But when I removed the lines closest to the grill and pump the brakes I get pressure and fluid squirting out.

Now I dont know how to "check" it properly though.

BTW, anyone know if you can purchase a new hydraulic check valve at Autozone, ect... or is this a dealer part?

 

If the lines where clogged wouldn't the brakes still get pressure just that wheel wouldn't work. I would think at least.

 

maybe.
Have you tried pumping them like 500 times? We changed the breaks on an astrovan a few years back. It took me like 3 hours to finally get the break pedal to not be hitting the floor with just minimal preassure. drive back and forth slowly, hitting the breaks hard every time. After a while the pedal got to be "spongy", and a while later it was where it was supposed to be. Had to add just a bit more fluid afterwards though.

I have NO idea if this was an actual method or if someone was pulling my leg and it just happened to work, but it did.

 

Hi,

You can check for a bad master cylinder by having an assitant slowly depress the brake pedal while you check for air bubbles in the master cylinder.

Also, how are the brake hoses's that lead to the calipers? Do they have bulge's in the lines? or did those lines ever become kinked, restricting the flow? That would explain somewhat of why you arent getting much fluid from the caliper bleeders. In most cases though, if those brakes hoses were kinked, the piston on the caliper would not retract. This is just some food for thought for you.

Im also assuming you are keeping an eye on the master cylinder as you bleed them right? Just dont let the master cylinder go empty or you will need to bleed that.

Hope this helps.

 

Thanks for the reply's so far, yes I made sure not to run the master dry.
The hoses looked fine to me.

Basically I am getting zero fluid coming out of the bleeder valve.

Tomorrow I am going to put a tube into some brake fluid and see if I am even getting air out of the bleeder when I have my dad hold down the pedal.

Im wondering if that proportioning valve has closed off the fluid to the front.

 

make sure you bleed them in propper order. passenger side rear, drivers side rear, passenger side front, drivers side front. this is the most efficient way of bleeding your brakes or you could break all the bleeders open and let gravity do its thing just make sure to keep an eye on the fluid levels and for which bleeder scews are starting to bleed.

 

I am assuming you are not pressure bleeding the brakes if I am wrong please advise.
The metering /proportioning valve will not allow fluid to go to the front brakes until the rear brakes seat against the drums. That is why the bleed sequence is important. Are your rear brakes definitely bled well enough to make the rear brakes move out against the drums and allow fluid to go to the front calipers? All metering valves do not have proportioning valves but since you have disk brakes you do. All proportioning valves that are working properly are self centering while metering valves alone must be re-centered after bleeding.
The master cylinder on our trucks has separate primary and secondary piston assemblies for the front and rear circuits so it could be the master cylinder. The front compartment is for the rear brakes. If you remove the rear line and replace it with a short piece of brake line that curves up and dumps back into the rear reservoir you can bleed and check the the master cylinder.
Does the interior brake warning light come on when you first turn on the key as it should? Does the light go off as it should or stay on when you start the engine and hit the brakes?
Proportioning valves the last time I checked were still a dealer item only but that has been several years ago.
Since you have vacuum, pull a vacuum on the front caliper and see if it holds. If it does then you can crack fittings along the line to find out where and if a line is plugged up.
I my opinion I would never replace a caliper without replacing the hose. The heat of the caliper is very hard on these hoses and you can't tell if one has collapsed inside by looking at it due to their construction, they have an inner and outer hose.