hi everyone, i am trying to get the brake fluid to fill lines from tag axle master cylinder to rear brakes. i have filled the master cylinder checked all the vacuum hoses. i am getting pressure to the bleeder valves (i can feel air pressure when brakes are depressed)but i cant get the fluid to fill brakelines. i have replaced te brakeline from master cylinder to the tee at the tag axle. i have tried to bleed them with the engine off and with it running.anyone have any idea what to do?

If you're finding air pressure at your bleeder valves when the brake pedal is depressed, there has to be fluid pressure in the system.

The only way I can think of that ouside air could be introduced into the hydraulic lines when the system is closed is if you're not closing the bleeder valve while the brake pedal is depressed. Leaving it open will suck air back into the lines when the pedal returns.

It's also possible that air was introduced into the main braking system when you replaced the line to the tag master cylinder.

Try this: crack the fitting at the tag axle end of your new brake line from the "T", & pump until you get fluid. Tighten that fitting then bleed the main brake system, front & rear. When you get no more air there, individually bleed the tag axle brakes, closing the bleeder valve at the end of each down stroke.

Make sure your master cylinders stay full throughout this process so you don't introduce more air into the system.

You have a lot ot brake line to fill, from the "T" on the drive axle to the tag axle master cylinder, & from there to both tag axle brakes. This may take some time. A remarkably small amount of air is removed by each stroke of the brake pedal.

Try pressure or vacuum bleeding.

You can also get a piece of tubing (I use clear) sized to fit snuggly over the bleeder valve nipple. Place the other end in a container partially-filled with fresh brake fluid.

Crack the bleeder, then depress the brake pedal slowly, release quickly; repeat.

This works for my trucks with ~144" WB - I don't know why it wouldn't work for longer runs...maybe olroy or bill h can comment.

That's the way to do it, Rusty. The length of the wheelbase shouldn't matter.

The way the tag axle brake system is set up on the P-30 suggests the system should be bled up to the tag master cylinder before you start on the tag. Any air in the lines up to that point will prevent the tag brakes from working properly.

I also have to go thru my brakes. If you all remember way back in April we found soft pedels and asked about master cyl.

Now we are getting ready to RV out of here come My and need to start down my list.

87 regal P-30 Chassis 454 with tag axle
93700 miles. That is 300 miles sinse we bought it last march from mike damm.

brake fluid reservore looks to be up by top of radiator but where is power steering reservore?

I am thinking about using a vacuum bleeder, Which one should I be looking at? I see a few for sale and not expensive for hand operated pump.

If I get this problem solved at least I will be able to stop without pumping 5 times first.


gordon

quote:

Originally posted by olroy:
That's the way to do it, Rusty. The length of the wheelbase shouldn't matter.

The way the tag axle brake system is set up on the P-30 suggests the system should be bled up to the tag master cylinder before you start on the tag. Any air in the lines up to that point will prevent the tag brakes from working properly.

------------------
Gordon B
1987 Barth 32' SE
454 P-30 Chassis
1998 Harley Electra Glide in Tow

quote:

Originally posted by gordonb:

If I get this problem solved at least I will be able to stop without pumping 5 times first.


gordon

Perhaps you should have an experienced professional do this.