Hydroboost problem

[Hydratech®]

Unless there is a foreign object that has lodged itself into one of the ports, it sounds to me like the control valve inside of the brake unit has hung up in the bore that it slides in. There is an exploded view on this page: http://www.hydratechbraking.com/Hydratech/tech.html What I'm referring to is called the spool valve, which is actuated by the spool valve lever. The spool valve is about the diameter of a nickle and about 3" long - the clearance to the bore it operates in is half a thou, so any dust or particulate can hang it up.

I recall years ago we did have a customer send a brake unit back in to us to have it examined for this type of problem, and we did find a foreign black rubber port plug / vacuum cap had been forced with hydraulic pressure into the 18mm adapter on the driver's side of the brake unit in such a way to plug it solid. Please remove everything from the 16mm and 18mm ports and examine visually with a bright light and a mirror just to be sure nothing has possibly gotten in there. When all is proper, there is literally a high pressure port to high pressure port interconnect that would allow you to blow through back and forth with a blow gun with no resistance. It is an open center hydraulic device and the valve doesn't start closing until you are requesting brake assist by applying pedal pressure (which is how this thing works by applying PS pressure to the backside of the power piston to provide brake amplification).

If you find no foreign objects creating a blockage, and cannot flow through the HP ports freely with compressed air, there IS a way to coax the spool valve back into a neutral / release position without having to get into the unit. Bolt it back up to the firewall securely, reconnect the pedal rod to the brake pedal. Next, unbolt the master cylinder and coax it out of the way while leaving the brake lines still connected so that you don't have to deal with brake fluid. What you're going to do here is to have a second person get inside and lift the brake pedal upward with about 10-20 pounds of force (don't get tempted to apply more force as it won't help and may hurt). While your helper is lifting upward on the brake pedal, you will be taking a hammer and tapping inward on the master cylinder pushrod carefully - don't blast it with a two pound ball peen, all it's going to take is about the hit required to drive a smaller finishing nail into let's say a wall to hang a 8 x 10 typical picture. With the helper inside lifting up on the pedal + you underhood gently tapping on the MC rod = will dislodge a hung up spool valve. You should then be able to blow back and forth through the high pressure ports without resistance, which means you can now also flow PS fluid. If you go back and look at the exploded view again, you will also see that spool plug at the front of the brake unit that can be removed, but trying to get the little retaining clip out that holds this rascal in is a PITA and this little devil likes to grow wings and fly across the shop into neverland sometimes (we all wear safety glasses, right?). If you do choose to remove the spool plug out of the face of the brake unit, you will be looking for the spool valve inside to be able to slide back and forth in the bore that it operates in.

Give this a good read and then go apply the suggestions to the scenario and let us know how it works out - it *should* take care of business for you. Should you prevail, I suggest you see if you can locate some of this stuff: http://www.lubegard.com/~/C-198/LUBE...uid+Protectant and also suggest you place a magnet inside of the PS reservoir.

I'll keep my fingers crossed that we can enjoy this end result:


NOTE: I strongly recommend that you do not disassemble the casting halves to attempt service, due the risk of having the accumulator discharge up to 1600PSI of pressurized PS fluid. While there is a very low real time likeliness of actual injury, there was a case many years ago where a dealer service tech died of hydraulic injection into the artery in his wrist while attempting service on a hydroboost unit. This is why Bosch no longer provides individual service parts and requires complete replacement of the entire brake unit if anything what so ever is deemed wrong with this type of brake unit. If you are somebody else reading this and just have to get inside one of these brake units, please firmly depress the brake pedal 10-15 times to discharge any stored pressurized PS fluid in the accumulator cylinder on the side of the brake unit. If the brake unit is already on a work bench, please carefully wrap the brake unit in a thick towel along the casting parting lines / midsection before attempting to separate the case halves to catch any possible high pressure spray of PS fluid.

[George Zinn]

Originally Posted by Hydratech

Like Mike says, I'm always here at least twice a day. Lat-G members can always look at my profile and get in touch with me directly as a result. First, take a deep breath, relax, and know that you now have my attention - I will work with you to get your scenario straightened out right here.

99% of this type of concern stems from having the adjustable brake pedal rod set incorrectly to not allow the brake unit to acheive a full state of release when the brake is not applied. Go ahead and crack loose the brake pedal rod adjustment under the dash and back off the adjustment (lowering the brake pedal height adjustment considerably to make sure the brake unit isn't being engaged or preloaded when not in use) OR disconnect the brake pedal rod from the brake pedal entirely for diagnostic purposes. If the PS system comes to life and all is now well, then we all chuckle about how adjustable items are infinitely more troublesome than non adjustable items.

I have a few questions: What model number brake assist system? What type of vehicle? 1st gen Camaro? Or? What type of PS pump? What type of steering gear? The more you can tell me about your specifics, the more accurate I can be within the diagnostic discussion. In cases like this, I also like to advise that a complete bypass of the hydraulic brake assist unit be performed, as the problem may not be related to the hydroboost unit at all. You can either take the two high pressure lines loose of the brake unit and then play some fitting games to interconnect them, or the high pressure hose from the PS pump to the brake assist unit can sometimes reach the steering gear as an easier bypass solution. As stated in the very first part of the system installation instructions, the power steering system must be in 100% condition to operate the hydraulic brake assist properly, so let's make sure the PS is functioning.

Let us know what you find and we'll take it from there.

Paul,

Several are wondering about the apparent changes regarding "Hydroboost"?
Is there a way and is it still appropriate to contact you directly regarding applications not listed on the website. Some (including myself), prefer to deal with "The Man" (that is you, in case you didn't know).

Please let us know the way forward?

My current application is for a 66 Ranchero that currently has a single bowl w/drums all around, that will ultimately have disc all around w/dual bowl. Do you know if there is enough room and if not are you the guy to send measurements too?


george

[Scott Norris]

Ok,Here is the latest update,Finally went ahead and tore it down,Did not find anything in the spool valve,But did find a peice of trash{aluminum chunk} wedged under the leading edge of the power piston.Dont know if this was it or not,but went ahead and cleaned everything with brake cleaner lubed with PS fluid and reassembled.Installed but did NOT hook up to pedal yet.It seems to work OK. Anyone who has one of these,if you can put a shiftkit in you can work on this system.It is very simple.Thank you Paul.

[Vegas69]

I wasn't crazy about no corporate contact when I was considering hyrdraboost. Let's face it, NOBODY knows there product like the originator.

[GregWeld]

Originally Posted by Vegas69

I wasn't crazy about no corporate contact when I was considering hyrdraboost. Let's face it, NOBODY knows there product like the originator.

HUH??

[Scott Norris]

But I would like to add,Paul you do need a contact # or at least hold some classes for your dealers,I called 5 of them and they all had the same answer for me,I JUST SELL THEM ,I DON'T KNOW HOW THEY WORK,. BUT I'LL TAKE YOUR MONEY.Sometimes us less experianced guys are hesitant to tear into a strange system. But THANKS AGAIN for the help.

[Scott Norris]

O Yeah,while I had it apart I got rid of that tiny O-ring fitting and tapped it 1/8 pipe.

[Hydratech®]

THIS is what happened to www.hydroboost.com...

Now, upward and onward! Right? Having scraped that BS off of our proverbial boots, let's move along now with the new url of hydratechbraking.com... Right about this time, I notice that Detroit is starting to show the first signs of economic blight. Hydratech Braking Systems is growing, to the point where long term decisions have to be made - do we stay in Detroit or ? If we stay in Detroit, we may never have an opportunity to relocate if desired or needed, as getting an established crew to move is dicey. We decide that we need to get out of Detroit, as I saw the economic downfall coming (seemingly before most others wanted to acknowledge it). Without going into all the details, we located a nice parcel of property to develop that would handle our immediate and future needs a mile down the road from the Nashville SuperSpeedway. We commenced construction of a new shop, and half way through the build the economy tanks badly into what has now been coined "The Great Recession". Isn't that just wonderful - we just recovered from our previous folly, and now here comes the next wave of extra strength Ibuprofen. The construction company was not adhering to the plans and specs, and this causes the financing to go sideways as the bank is looking for any excuse to bail. Now the economy is tanked, and we are scrambling around to get alternate financing to finish the build (are we having fun yet?). Never mind that now we have also gotten sideways with the county, as it turns out they wanted our parcel of property for a new commerce center to build. Here we go again with more funds being spent with attorneys! Oh and did I mention the further expenses in having to operate in temporary industrial slots while everything is sorted out? Let's not overlook all of the mess in process to cause Crane, Holley and other notable companies to have to re-organize. Had enough yet? If you would even believe after all of this, there is actually more. I don't even want to get into how a previous machine company we used has recently been identified as having stolen our intellectual property and is now using our designs and patterns.

As you can imagine, all of this has led to us being closed to the general public. We now are "dealer only" as a result (and know that this has ruffled many feathers), but we need everyone to know that this is for no other reason than the survival of Hydratech Braking Systems. We hope that 2010 will bring a period of stability and a chance to get back on the right track. We do ask that you do the best you can to understand and bear with us, as we are operating under less than optimum circumstances. All this being stated, I ask that mainstream inquiries and general communications be handled through our dealers until further notice. If you have needs that cannot be properly handled through our dealer network, go ahead and send an e-mail in to "info at hydratechbraking dot com". I would also like to note that all installation instructions printed as of our move to TN have had the updated e-mail address listed on the last page, so that channel of communication has always remained wide open. Do please note that private messages on the forums will not work well as I do not log in when surfing through. I hope that every one that has read this now has a better understanding of what it has involved to bring Hydratech units into continued existence!

George, there is just not enough room between the firewall and the shock tower in your '66 Ranchero to install one of these brake units. The brake unit comes in at roughly 6 1/2" to 7" of installed length, and then you add the length of the typical master cylinder at 7 1/2" to 8" (grab a tape measure and see what you've got). The good news is that the American Brake and Steering "Electric HyPower" setup fits and provides similar levels of power assist.

Scott, I'm glad to hear that you have managed to straighten your brake unit out without any hassles.

[70rs]

Best of luck for you in 2010 Paul.

[monza]

Thanks for the informative read, all the best moving forward.

Love my Hydratech Brakes! Stopping is almost as fun as starting....