Early bronco proportioning valve install

This will be your point of no play. Bolt the master cylinder to the booster. You should always bleed the master cylinder to get rid of any air. Air in the master cylinder will go straight into the brake lines and make it that much harder to bleed the system afterwards.

Pick up a simple kit from your local parts store, which will include various size fittings and 2 rubber lines. Thread the fittings into the master cylinder, attach the tubes and loop them back into each reservoir.

Just cut them and bend them back into the reservoirs. If you are bench bleeding use a large screw driver to push on the master cylinder Keep an eye on the brake fluid level and add fluid as needed to be sure the tubes stay submerged. When you stop seeing bubbles the bleeding is done. Brake fluid is almost as bad as paint remover.

You may want to lay a rag under your master cylinder while bleeding to avoid spilling any fluid onto painted surfaces. The H-block shown is the most common configuration on drum brake Broncos and is always confused with a proportioning valve.

We highly recommend getting new brake lines. The brake lines we carry fit perfectly and made the install simple. If you need to adjust them be very careful not to crimp or make any sharp bends. Always use flare wrenches when working with brake line fittings. Normal open end wrenches can round off the corners. Brake lines seal using the flared seat at the end of the lines, not the threads. Attach the supplied vacuum hose to the check valve at the booster.

I haven't done the MC mod on the factory MC, but if you do a search you'll find it fairly easily. First pic is an H block, second is a prop valve. Tiko Bronco Guru. Joined Jul 9, Messages 1, I just did this about two weeks ago. Joined Apr 18, Messages 2, Loc. This is where I put mine. DirtDonk Contributor. Joined Nov 3, Messages 41, Nightstick's is a clean install considering he's got headers.

And that's the kicker sometimes, as header tubes can get real close to a frame mounted prop valve. I prefer the higher mounts like the others showed for that reason alone. But add to that the more easily accessible spot, and you have a winner.

Really though, how much access to you need for a part you may or hope to never touch again over the life of the truck? But protection from heat is always a good thing. I think most opt to custom make their brake lines to fit it up high, but there are in fact kits to mount this "stock" type valve up on or near the master as well. It's an item we should be carrying in my opinion, but still only have the stock type frame mount brackets as far as I know. Yes, they can be utilized together for ease of plumbing, but I'm pretty sure that most install a prop valve in place of the original H-valve and not in addition to.

So not sure if there is much data on what works best and why. Heck, most of this stuff ends up being custom modified by the end-user anyway! Good luck. DJs74 Bronco Guru. Joined Apr 1, Messages 1, DirtDonk said:. I appreciate the advice guys. My preference was to mount it up near the MC, however my kit did not come with that mounting bracket, I know they are easy to find, just want to wrap this project up. If the H-block needs to come out which seems to be the suggested method it makes sense, to me, to just remount the new pro valve in its place down on the frame.

My hope was to avoid working in that area at all but it doesn't appear that anyone knows for sure how the pro valve and H-block would work in conjunction but my suspicion is, not well.

Unless I can get a bracket to mount to the MC in short order I'll probably just mount it to the frame. EarlyElway said:. DJs74 said:. I think the principle behind the new proportioning valve is to distribute fluid appropriately to the two different philosophies of the brakes types But that is an assumption based on reading not doing DJs Well fellas I got it in last night and it really wasn't to bad.

I ended up cutting some of the old brake lines as I couldn't break the flare net loose. I have all lines hooked up except one short one for the front brakes. I should have that done tonight and be ready to bleed the lines and see if it all works. Thanks for all your help. Turn the ignition switch to On so that the brake light switch is lighted up. If the problem that caused the light to trip was in the front, start at the rear wheel cylinders.

If the problem was in the rear brake system, start at the front wheel cylinders. Start by bleeding one of the wheel cylinders and attempt to bleed it until the brake pressure valve resets and the light goes off. If the light turns off and then back on, you have bled too much and will need to bleed the opposite wheel cylinder to compensate if you were bleeding the rear wheel cylinder, you will need to move to the front and vice versa.

Once the bleeder is tight, release the pedal and pump it a few times to make sure the light stays off. If the light stays off and the brake pedal is firm, the job is complete.