Hydroboost

[CityHick]

Update: I installed the rear brake delay device, which involved redoing my rear brake line. The new brake line flare tool that I bought works pretty nicely - I have no more leaks. I bled the system today and went for a test drive. Braking performance is still lackluster.

On a positive note: my bronco now stops totally straight with the rear brakes no longer locking up before the fronts. There is no hint of any sideways influence under full braking. The problem is that none of the brakes lock up now. I can definitely tell that the fronts are doing "something" but it appears they're not doing enough.

I went through the process of adjusting the proportioning valve all the way from least pressure to max pressure. I can tell that the rears are braking sooner at max pressure than they are at minimum pressure, so I know that the adjustable valve is doing its job.

I've decided to invest in a brake line pressure gauge. I remain convinced that my front brakes are (and always have been) the root of the problem. I don't think they are grabbing hard enough. As I may have mentioned earlier in this post, I replaced the front pads as one of my earlier steps in the process. I have also pulled the front calipers off and ensured that. the slide bolts are lubed. I have no doubt that the booster is doing its job; the pedal pressure required to "floor" the brakes is significantly lighter with the engine running than it is with out the assist.

When I receive the pressure gauge, I will do further investigations and see where this leads. This entire past week I was pretty occupied with work and after-work activities so I had very little opportunity to look at this in the evenings. This coming week looks better. Next weekend I have plans to take my nieces to an event (something I don't get to do enough of, so I am taking advantage of the rare opportunity). So it may be another couple of weeks before I make significant progress again.

If I continue to have problems, I'm going to start searching for a shop or an individual who can do further diagnostics. So if anybody reading this is able to come help me, you'll be compensated at minimum with a nice meal and some tasty beverages - or cash if that's what it takes.

It did feel good to fire up the bronco and cruise around the 'hood today even with the poor braking performance... I am motivated to fix this once and for all; these warm (but not hot) days are prime Bronco driving weather. I'd really like to load up with gear and go get lost for a few days in the rig, soon!

[71BRONCO71]

It sounds like the Chevy brakes are the problem tony.
those came off a 1979 Chevy and your rear brakes are probably a lot newer style.
I was never impressed with the Chevy conversion on mine. I swear the stock drums worked better.
Now I run the larger Ford setup and i can lock the front up if I really try hard to.

[CityHick]

Sadly that seems the likely answer, Ryan.
I want to replace my steering knuckles anyway - a previous owner did some things to them that I don't like. This may be the second hint that I need, to push me over the edge to change to the Ford brakes and later model Ford knuckles.

[CityHick]

Update:
I added speed bleeders to all 4 calipers and bled the brakes again, the old fashioned way of pumping the brake pedal. This resulted in a much stiffer pedal than I'd achieved at any point before. It never felt spongy, just light and I figured that might be characteristic of the new system. I was wrong.

I was able to drive my Bronco to the gas station and fill up. First time it's left the neighborhood since October or November.

With the brakes now working, I proceeded with cutting the old shock mounts off and welding new ones on to clear the calipers. I ended up slicing one of the rear brake lines when the angle grinder got away from me. Whoops. Cannot find the same soft line as what came with the WH kit, so I will be ordering a replacement from WH and installing it sometime soon. Of course this means that I'll be pulling the master cylinder again, bench bleeding it again, bleeding the entire system again, and hoping for the best.

I will say that it felt great to drive my bronco further than around the block. This lengthy thread is finally coming to a close.
Thanks for watching.

[904Bronco]

Finally! Must feel Good Tony Congrats!!!

[GloNDark2]

Right on man! That is awesome. I have been thinking about trying the speed bleeders. Now just have to figure which ones with my mix of calipers. haha

[CityHick]

I am hoping to not have to bleed the brakes again for a long, long time. It takes forever.
Quick note - with speed bleeders, my vacuum bleeder device no longer pulls fluid through. So that's a bummer. And pumping the brakes takes a long time, too. Anyway... I spent a while this weekend dialing in the adjustable proportioning valve. Found the spot where the rears lock first (despite the aforementioned device which is supposed to limit that). Then turned it to where the rears won't lock at all. It seems fine - there's a lot more "nose dive" now when I slam on the brakes. Stopping performance is good but I think all the internet claims of slamming one's face into the windshield are drastically overstated...

Anyway... onto the next thing. My (old, old) BC Broncos heim steering linkage has long been annoyance. It is not an urgent fix, but it is something I'd like to replace. I'm going to hold off on this until someday when I decide to replace my front knuckles. I'll find a better steering solution at that time. Overall my bronco seems fine for now. but that just means something else is about to fail. lol. Until next time, folks...

[ba123]

Glad you got it going!

[ba123]

Finally got my own stuff installed. Haven’t run the PS lines or bled the brakes but the master is bled and in.

Gotta say, I’m surprised how crappy the bench bleed process went. I tried the little plastic adapter that looked the best for me (red ones) and they sucked. Literally! They sucked air somehow, even though tight. I made a nice big mess changing to the orange ones and those worked great.

not sure how many hundred pumps I did on the red before I decided it was time to call it. One side was good and the other was not.

[CityHick]

Finally got my own stuff installed. Haven’t run the PS lines or bled the brakes but the master is bled and in.

Gotta say, I’m surprised how crappy the bench bleed process went. I tried the little plastic adapter that looked the best for me (red ones) and they sucked. Literally! They sucked air somehow, even though tight. I made a nice big mess changing to the orange ones and those worked great.

not sure how many hundred pumps I did on the red before I decided it was time to call it. One side was good and the other was not.

YES! I've never had so many problems bleeding a master cylinder before. It took forever. I actually exchanged master cylinders once, in addition to exchanging the first booster after a very early failure. I am not at all impressed with this "kit". It appears complete, but imo the parts are a little scary. This is my life riding on this system...

I am once again fairly disenchanted with all things bronco. I've not so much as driven mine in months. I'd be tempted to let it go if someone came along with a fistfull of dollars...it's not for sale, I don't really have any intention to sell, but on the right day I'd probably let it go. It's kinda sad to see it sitting there unused.

I have a handful of other little annoyances to track down, some of which will probably result in excessive amounts of money being spent again, but such is life with a 50+ year old rig...

[ba123]

As I made more progress including buttoning up the lines, filling and pressure bleeding I did notice a couple things. I had problems with WH flares, a couple leaked and I had to loosen, tighten loosen again. NONE of my own flares leaked. I also got a bad front caliper from Napa, which they gladly exchanged for me and all good, but was a pain since the drivers front made it so I had to reveled everything. I made a custom pressure bleed cover by getting an extra cover and modding it and o don’t think you can bleed this system the old fashion way properly. Had to do it twice and took fewer than 5 minutes each time aside from clean up but highly recommend doing that. I plan on RE bleeding again after I’ve driven a couple hundred miles.

Overall, I like the kit. The prob with the master bleeding is Wilwood. The instructions could be better, and of course the glaring could be MUCH better. I hated the dumb little loopty hard front line from the bracket to the drop hose. I cut the fittings off and made a nice new one. I don’t see the point of those wonky loops.

[CityHick]

Interesting idea getting that extra cap. I may have to do the same thing...
You have some good parts in the background of that photo - Dakota Digital module etc.

[ba123]

Interesting idea getting that extra cap. I may have to do the same thing...
You have some good parts in the background of that photo - Dakota Digital module etc.

Thanks! I originally got the Motive adapter for this kind of master but I thought the idea sucked and decided to do this. Was about the same cost and absolutely perfect. There are two holes in the cap to let air in on top of the gasket so is can collapse down. You have to plug one and drill the other to make a fitting and then cut the entire inside out of the second gasket so fluid can go to both sides, or you could use two fittings. When you let air back into the system, the reverse pressure pushed the extra fluid all back and I got no overflow both times, but I’m sure the quick connect helped too since it seals when you disconnect. Then I just connected the cap and held it up to drain the line. And I used a fuel injection hose clamp for the hose.

On the Dakota stuff, yeah, I have plenty with my gauges and then a Megasquirt BIM module and also a Vintage Air controller box (not there though) and then also have Digital Guard Dog stuff in there for keyless, remote start, ignition disable, 4g gps tracking and using the lid to attach my gps sensors to, which should work though the plastic and then my fiberglass hood (I hope).

I had it all tucked away but doing a couple more things in there and making a big mess. Multitasking…

[CityHick]

While I like the idea of remote start (and use it on my daily driver, often), my Bronco is a manual transmission and I have visions of remotely starting it up in gear...
I'm interested in the Megasquirt ECU idea. I run a stock Mustang A9L ECU; but I have a 351w with a mix of Mustang and Explorer EFI components. It works, actually runs well but I've always been curious how much better it could get with some tweaking. Not to mention it does make me nervous running a 30 year old ECU (despite the fact that it's been refurb'd). I am a software engineer-turned-manager and thus my technical mind is a little starved lately. I like to tweak with stuff...

[ba123]

While I like the idea of remote start (and use it on my daily driver, often), my Bronco is a manual transmission and I have visions of remotely starting it up in gear...
I'm interested in the Megasquirt ECU idea. I run a stock Mustang A9L ECU; but I have a 351w with a mix of Mustang and Explorer EFI components. It works, actually runs well but I've always been curious how much better it could get with some tweaking. Not to mention it does make me nervous running a 30 year old ECU (despite the fact that it's been refurb'd). I am a software engineer-turned-manager and thus my technical mind is a little starved lately. I like to tweak with stuff...

No worries on the in-gear as long as you don’t bypass the neutral/park safety feature built into the remote start stuff. If you do and it’s in gear, it wont start. I use it all the time on my daily driver as well and really not sure how often I’ll use it on the bronco but since it wasn’t much more to add and not much more work, I figured it would be cool to have if I want it.

im really happy with the testing so far of this Digital Guard Dog stuff and since I bought so much stuff, they offered a better deal when I asked them directly and mentioned the prices on their site vs on Summit. I think that made it easier for them to call it price matching but they made me a much better deal. Not cheap but seems great. I haven’t yet turned the engine over with it, but it’ll also handle 40amps on the starter circuit so no problem wiring directly to my mini starter. Engine compartment is clean with no clutter, not even wiring seen.

For the Megasquirt, we’ll see how that goes but I think I’m set up for a first run soon. Was able to eliminate the MAF, since you don’t need it with a proper tune, I have a big BXR intake and larger injectors, I have trans temp and oil pressure with rules set up to the ecu. I have the ecu controlling my AC on/off circuit with delay and idle up and also have the ecu controlling my electric variable pwm fan. I thought about going pwm fuel pump and no return but decided to stop with the million things I’m already doing.

I also went coil near plug so have a coil per cylinder you can probably see 4 in that pic on the firewall to the right of the Hydroboost.

I went with Stinger PiMPxs for the Megasquirt ms3 and it does somewhat of a self tune that you just drive for 30 minutes and then you can fine tune what you want different afterwards. Also, I have it so that the BIM module shares information between the ecu and the Dakota Digital dash so just one sensor for each thing and they both get the information. Took a good amount of bench testing to get it all set up right but happy to share any info if you need it.