Hi, guys.
I learned a week ago that I'd be taking a long trip in two weeks(next weekend) with a heavy trailer, helping a friend move.
I took a short trip with my trailer, and found that while my trailer worked just fine, my brakes were a bit lacking.
Especially when doing some slight pumping of the brakes, to keep things cool on a long downgrade.
After running out of vacuum boost a couple of times, and having to really stomp on the pedal to get some brakes, I decided to go with a hydroboost conversion.

Now, to be fair, I'm sure my vacuum booster is probably worn(though it didn't seem to be leaking), and my vacuum pump isn't producing like it used to, but if I'm going to spend money on new stuff, I figure I should do things "right"!

So I didn't.

All the hydroboost topics around here talk about a reasonable conversion, involving a Hydroboost unit off a F450 of the same vintage, an upgraded pump reservoir, etc. Using anything else wasn't recommended.

So that's exactly what I did.

See, I saw that the price of a new Hydroboost unit was at least $250, plus all the hoses and parts. When I went to my favorite wrecking yard and found that they had an '03 E350 based transit van with 6.0 diesel and a hydroboost unit, I asked how much for the unit, brake pedal, pump etc.
When I was told $80, I decided that I would just have to make it work.
(Note: I ended up not being able to get the pump off, so the guy gave me a discount... $50 for everything!)

Here's the main unit, as it stood when I got it:
imgur: the simple image sharer

I then went to work on modifying it, as time allowed, after work. Note that I'm a machinist, so I had access to some decent tools.
I pulled a spare (shot) brake booster and MC from my scrap pile for measurement purposes.

When I measured everything I found:
1. HB Hole mounting pattern was off. The difference was small enough I couldn't make an adapter plate easily, but large enough to make it a pain to fit.
2. Pedal shaft was too short, but surprisingly the hole at the end was the same size.
3. HB->MC pin was sticking out too short.
4. HB->MC bolts were too far apart on the HB unit.

I started with #2. Cut the shaft, made a small cylinder with holes at each end for the shafts, and enough spacing in the middle to space it out. Added a couple of set-screws to keep the whole thing together: imgur: the simple image sharer

#3 was solved with a little bullet-shaped cap which slid over the end of the existing HB shaft, and slid into the MC hole: imgur: the simple image sharer imgur: the simple image sharer

#4 was solved by wollowing out the holes in the HB until it fit. I clamped the whole thing upright in a mill and just slotted the holes.
Final: imgur: the simple image sharer

Finally, I had to solve #1. I did it by beating the original bolts out of the plate, and drilling out the holes to 5/8". Even that wasn't quite enough, but that plus a little wollowing in the truck did.


Yesterday, I got to installing it.
I unbolted the MC from the old booster, then unbolted the booster. Yanked the booster without causing any other problems: imgur: the simple image sharer
(Note: I used my DeWalt 18 Impact driver, with a hex->3/8" adapter, long extension, 3/8" impact-grade universal and socket to do this. Took like a minute to get *all* the bolts out.)

Wollowed out the holes, got it bolted into place.
The upper pair of holes worked OK, the lower ones were still too low. I just marked and drilled new holes in the HB attachment plate for the lower ones. It was a total pain getting the thing together by myself; if you can do it with help, it will be a lot easier.

I then attached hoses - I attached the pressure line from the pump to the side closest to the pedal, marked X, and the line to the steering unit to the other side, marked Y. Return lines got Tee'd into the existing return line.
imgur: the simple image sharer

Note that I never drained the PS fluid or anything. I just wiggled the old return line off the pump, plugged my Tee into it, plugged the return line into the tee and called it good. Yes, it was slowly pouring fluid for the few seconds there was no line on the bottom of the pump, but I only lost a couple of oz.

You can see my tee here:
imgur: the simple image sharer

I tightened everything up and tested it out.

Now, as it turned out, I did it wrong. My hoses were backwards!
It still worked... somewhat. I had some power brakes, but turning the steering reduced my braking, and while it was drivable, it didn't seem any better than my old vacuum booster. The PS pump was also screeching whenever I'd touch the brakes, and it sort of... ran out of power slightly down the pedal.

This evening, I started making a video to show you all about it, and ask for advice, when I happened to start turning the wheel while holding the brakes... and as I did so, my foot started going down. I realized things were backwards, and the fluid going through the PS was what was powering my HB unit.

Swapped the hoses, started her up... nice, consistent pedal, massive amount of boost... totally effortless. I can lock the wheels up without a huge amount of force, and *easily* throw everything not nailed down forwards. It's also quiet, until I give it a lot of pedal.
It's *perfect* now.

In the next few days I'll upload my videos of how it works.


But in the meantime... I get to drive awesomeness! :P

 

Just make sure the rest of your brake system is up to the higher pressures-

 

I would not trust the extended push rod with set screws. Got a welder?

 

pics done work for me

 

X2. Being a machinist means it shouldn't be hard to make a longer push rod I would think.

 

Actually, I'm not too worried. My extension is solid in the center portion, the actual 'extension' part.
It would actually work just fine without *any* set screws -- pushing on the pedal results in direct metal shaft-spacer-shaft linkage; when releasing the pedal, the bottom shaft will push up on the pedal, keeping support.
The only reason for the set screws is to allow me to /pull/ on the pedal if I ever need to, and keep things together during installation.

Now I *might* weld a bit of shaft in there at some point, but this is actually stronger than any weld, and as I'm not relying on any set screws to do anything important...

Note: videos will hopefully be up Tuesday; things have been hectic.

 

Finally got my videos uploaded:

With lines backwards:
<_< That moment when I realize that I connected it wrong.


With lines correct:

 

Glad you got it figured out, sounds like a good upgrade. I may do HB myself someday if I ever run across the parts.

 

Lol... I did something similar, and retro-fitted a Super Duty HB onto my '94. Not something I would ever tackle again, even though the second time around would be much easier since there wouldn't be anything left to figure out.