Hydroboost Planning

[85lebaront2]

Ya'll are right - memory loss is a pain!

Anyway, the mystery is solved. I have the wrong bracket installed. It is a C2 bracket that has never been broken and is nicely powder coated. Bill - do need such a bracket for Darth?

Below is a pic with a C2 bracket on the top and a Saginaw bracket on the bottom - with a Sag pump installed. (That's the bracket and pump Jonathan sent to me - thanks again!) Note that the Sag bracket has been neatly repaired where the bottom tab was broken off - probably because someone didn't install the plate behind the water pump. And note that the C2 bracket is still broken - and I know why it was broken as it was on Huck and had no backing plate.

Also, note that the Sag bracket only has holes for three bolts, even though the pump itself has four bolt holes. The Ford application didn't use the fourth bolt hole. And therein may have been why and where I erred. I knew that a Sag pump has four bolt holes, so I assume I looked at the three brackets I have and realized all three have three bolt holes, but didn't look at the spacing. Given that I picked the best of them - the one that hadn't been broken. (That's my excuse and I'm sticking with it. )

But obviously I chose poorly. So now I'll have to blast and PC the Sag bracket. Sure glad it was caught at this point as that won't be all that big of an issue. However, I'll then need to sort out the pressure hose, although Jonathan has given a good solution.

And then there's the return, and both Alfie and Jonathan have said just teeing it into the normal return will work. Or, I could either try to find a hydroboost reservoir or braze a return fitting into this one.

Now we are back on track! Thanks for bringing me back gently.

Glad you found it! No, I have a nice blasted and clear coated C2 bracket, it is sitting on the new engine. I thought I had a picture of the C2 and Saginaw brackets side by side, but I haven't found it yet.

[Gary Lewis]

Glad you found it! No, I have a nice blasted and clear coated C2 bracket, it is sitting on the new engine. I thought I had a picture of the C2 and Saginaw brackets side by side, but I haven't found it yet.

Thanks, Bill.

I got to looking at the hoses coming out of the hydroboost unit and decided I'd check out the 1995 FSM to see what it shows. And in order to make that easier I carved those pages out of the FSM and put them here: Documentation/Driveline/Brakes and then the Master Cyl's & Boosters tab, then the Factory Shop Manual Sections tab, and finally on the Hydroboost tab.

Here's what it says in the Description And Operation section:

The Bendix Hydro-Boost brake booster is a hydraulically operated brake booster powered by the power steering pump (3A674). The power steering pump provides the fluid pressure to operate both the hydraulically powered power brake booster (2005) (hydro-boost)and the power steering gear (3504).

A hydro-boost reserve system (accumulator) stores sufficient fluid under pressure to provide at least two power-assisted brake applications in the event the power steering pump fluid flow is interrupted.

The brakes can also be applied manually if the reserve system is depleted.

Model identification is stamped into the power brake booster housing near the power steering right turn pressure hose (3A717). With the Hydro-Boost at rest (engine (6007) on, brakes released) power steering fluid flows from the inlet port, across the number 3 land and through the outlet port to the steering gear. In this position, steering pressure created by the steering gear and power steering pump is isolated from the boost cavity by the spool valve. Lands 2 and 4 block this steering pressure which prevents activation of the unit.

Any leakage goes directly back to the power steering oil reservoir (3A697)

And here's what it shows for the plumbing of the F-Super Duty Chassis Cab, and you can see the C2 pump with the two returns, one on the neck for the hydroboost and the other on the back bottom of the reservoir:

Here's what it shows for the Commercial application. Note that they use a tee for the returns.

[ArdWrknTrk]

Thanks, Bill.

I got to looking at the hoses coming out of the hydroboost unit and decided I'd check out the 1995 FSM to see what it shows. And in order to make that easier I carved those pages out of the FSM and put them here: Documentation/Driveline/Brakes and then the Master Cyl's & Boosters tab, then the Factory Shop Manual Sections tab, and finally on the Hydroboost tab.

Here's what it says in the Description And Operation section:

The Bendix Hydro-Boost brake booster is a hydraulically operated brake booster powered by the power steering pump (3A674). The power steering pump provides the fluid pressure to operate both the hydraulically powered power brake booster (2005) (hydro-boost)and the power steering gear (3504).

A hydro-boost reserve system (accumulator) stores sufficient fluid under pressure to provide at least two power-assisted brake applications in the event the power steering pump fluid flow is interrupted.

The brakes can also be applied manually if the reserve system is depleted.

Model identification is stamped into the power brake booster housing near the power steering right turn pressure hose (3A717). With the Hydro-Boost at rest (engine (6007) on, brakes released) power steering fluid flows from the inlet port, across the number 3 land and through the outlet port to the steering gear. In this position, steering pressure created by the steering gear and power steering pump is isolated from the boost cavity by the spool valve. Lands 2 and 4 block this steering pressure which prevents activation of the unit.

Any leakage goes directly back to the power steering oil reservoir (3A697)

And here's what it shows for the plumbing of the F-Super Duty Chassis Cab, and you can see the C2 pump with the two returns, one on the neck for the hydroboost and the other on the back bottom of the reservoir:

Here's what it shows for the Commercial application. Note that they use a tee for the returns.

I think I'd be looking for a barbed brass Y in the big box plumbing section.

At least that way both returns have the same chance and balanced flow.

[Gary Lewis]

I think I'd be looking for a barbed brass Y in the big box plumbing section.

At least that way both returns have the same chance and balanced flow.

Jim - That seems to be the easiest approach for the return.

Having said that, I'm confused again. Do you remember which tube you cut? In other words, did you cut it off the steering gear or the power steering pump? (I think it was probably the one to the steering gear?)

I ask because something is not adding up. First, Jonathan says the line from the pump to the booster on the SuperDuty shouldn't fit the Saginaw pump. But this looks to be a perfect fit as the line has a tip that should engage in the o-ring perfectly. And it screws in nicely.

But here's the C2's outlet and it doesn't have that o-ring. Is it the right fitting?

I thought I could clear this up by going to the '95 FSM's diagram shown above, but that confused me even more as it says the connections are to the Power Steering Oil Reservoir, Power Steering Right Turn Pressure Hose, and Power Steering Left Turn Pressure Hose. Huh??

So I looked at another drawing in the FSM and it seems to say the front one is the return, the middle one the supply, and rear one goes to the steering gear. Does that seem to make sense? The middle one is the one with the fitting still on it and it seems to fit the Saginaw pump nicely.

And if that is the case then the line I need is the one from the hydroboost unit to the power steering gear.

 

[ArdWrknTrk]

Jim - That seems to be the easiest approach for the return.

Having said that, I'm confused again. Do you remember which tube you cut? In other words, did you cut it off the steering gear or the power steering pump? (I think it was probably the one to the steering gear?)

I ask because something is not adding up. First, Jonathan says the line from the pump to the booster on the SuperDuty shouldn't fit the Saginaw pump. But this looks to be a perfect fit as the line has a tip that should engage in the o-ring perfectly. And it screws in nicely.

But here's the C2's outlet and it doesn't have that o-ring. Is it the right fitting?

I thought I could clear this up by going to the '95 FSM's diagram shown above, but that confused me even more as it says the connections are to the Power Steering Oil Reservoir, Power Steering Right Turn Pressure Hose, and Power Steering Left Turn Pressure Hose. Huh??

So I looked at another drawing in the FSM and it seems to say the front one is the return, the middle one the supply, and rear one goes to the steering gear. Does that seem to make sense? The middle one is the one with the fitting still on it and it seems to fit the Saginaw pump nicely.

And if that is the case then the line I need is the one from the hydroboost unit to the power steering gear.

I'm fairly certain that I cut the line off the sector box.

I didn't have a crows foot.

As for the rest.... if the line fits, wear it.

I have not enough experience.

I've only done a couple of swaps (long ago)

I used a van line for the E-350 donor and tweaked the hardline S at the box so it fit life an F-series.

No Hydroboost there.

[Gary Lewis]

I'm fairly certain that I cut the line off the sector box.

I didn't have a crows foot.

As for the rest.... if the line fits, wear it.

I have not enough experience.

I've only done a couple of swaps (long ago)

I used a van line for the E-350 donor and tweaked the hardline S at the box so it fit life an F-series.

No Hydroboost there.

If the cut one is off the sector box, which seems to be the case, then I think the line from the pump to the booster may work. It has to be twisted a bit to connect, but I may be able to help that some.

I'll do some more checking tomorrow.

[Ford F834]

If the cut one is off the sector box, which seems to be the case, then I think the line from the pump to the booster may work. It has to be twisted a bit to connect, but I may be able to help that some.

I'll do some more checking tomorrow.

Gary, I’m not remembering all of the gory details but I’m pretty sure that the C2 fitting won’t seal right on the Saginaw and it will leak. When I did mine that end was cut off, and replaced with a universal union and a fuel line fitting that matched the van Saginaw hose end:

[Gary Lewis]

Gary, I’m not remembering all of the gory details but I’m pretty sure that the C2 fitting won’t seal right on the Saginaw and it will leak. When I did mine that end was cut off, and replaced with a universal union and a fuel line fitting that matched the van Saginaw hose end:

Jonathan - In your first pic is the cutoff end the one off the C2 hose? If so, do you have one that shows the business end of it? Yours looks to be flat or maybe flared on the end similar to the fuel line one in the 2nd pic.

But my fitting has a tip on it that sticks out, and it has a taper that seems to be perfect for the fitting on the Sag pump. Which doesn't make sense as it came from a C2 pump.

You didn't send the hose from the van, right? Do you remember what year? Perhaps I could persuade the local parts store to order one in and then make me a hose like that but with the correct length.

[Ford F834]

Jonathan - In your first pic is the cutoff end the one off the C2 hose? If so, do you have one that shows the business end of it? Yours looks to be flat or maybe flared on the end similar to the fuel line one in the 2nd pic.

But my fitting has a tip on it that sticks out, and it has a taper that seems to be perfect for the fitting on the Sag pump. Which doesn't make sense as it came from a C2 pump.

You didn't send the hose from the van, right? Do you remember what year? Perhaps I could persuade the local parts store to order one in and then make me a hose like that but with the correct length.

Sorry Gary, I don’t think I do have any other pictures of the C2 end that was cut off... but I don’t remember a tapered cone on it. That is opposite of the flare on the Saginaw line, but I don’t see a flare inside the pump fitting anyway. I don’t think that is where the seal happens. I think it is the shoulder and O-ring on the Saginaw line that holds the pressure. I have no ideas if the cone and O-ring would seat and do the same thing? 🤷‍♂️

[Ford F834]

Jonathan - In your first pic is the cutoff end the one off the C2 hose? If so, do you have one that shows the business end of it? Yours looks to be flat or maybe flared on the end similar to the fuel line one in the 2nd pic.

But my fitting has a tip on it that sticks out, and it has a taper that seems to be perfect for the fitting on the Sag pump. Which doesn't make sense as it came from a C2 pump.

You didn't send the hose from the van, right? Do you remember what year? Perhaps I could persuade the local parts store to order one in and then make me a hose like that but with the correct length.

And to answer your other question... no I did not send the van line since it was not for hydroboost. It was extremely short and went straight to the gearbox. There were no Ford vans with hydroboost that I know of. The vehicle was a ‘95 E350.

1. You could try what you have, but I would wrap it with rags in case it leaks it won’t spray and make a mess.

2. You could have the end changed like I did, parts and labor to crimp on the universal union was a bit over $50. The steel line is cut-to-length which saved me on my long I-6.

3. Order the Chevy line (~$20) and return it and try #2 if it does not fit or work for some reason.

4. There is supposedly a way to adapt the fitting, but my understanding was it wasn’t just a single part, and I was unable to confirm exactly what I needed and adding more joints that could leak didn’t thrill me.