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NickP
02-01-2014, 08:45 AM
Question: What effect on the performance of the system does the use of either standard flex hose or braided flex hose have?

I have a Kugel 90° pedal assembly (under dash) unit. I have reversed its direction due to interference with stereo and other items within close proximity. I am now in the process of lowering the master cylinder mount surface to gain two things – underside of cowl to master cylinder clearance and the required distance for remote reservoirs to master cylinder.
What needs to happen is the use of very short sections of braided stainless flex to the supply line for the ABS electric system. Normally, these lines are hard lines but the space limits assembly under the dash but would allow access were it a flexible connection.

I can purchase preassembled certified lines in #3 Flex Stainless but if the addition of too many of these types of connections lessens the pressure due to the dreaded bulge that has been talked about then I’ll have to take a different direction.

As always, many thanks in advance.

chevynut
02-01-2014, 09:25 AM
The expansion of the flexible lines doesn't really lessen the pressure, it just makes the pedal softer. If you push with the same force, you will get the same pressure out.

It seems strange to me that a hard line wouldn't fit where you can put a braided line. But I personally don't see any issues with using braided stainless teflon hoses.

If it's the supply line to the ABS system that's the issue, why are you worried about pressure? Is it the line from the reservoir to the ABS unit you're working on? Seems like a supply line should be larger than -3.

NickP
02-01-2014, 12:39 PM
Are you still using this: http://pic20.picturetrail.com/VOL97/465705/4874799/303392820.jpg

chevynut
02-01-2014, 01:53 PM
Yes Nick, that's still my setup. Only part of it is shown in that picture. I have -6 flex lines from the remote reservoir to the block on top of the MC, then another -6 flex line from that block down to the inlet of the pump. The outlet of the pump to the MC is fitted with a -4 hard line, because it's at 2500 PSI or so. Then I have two -4 flex lines down to the frame for front and rear brakes. I don't think they're going to be a problem.

NickP
02-01-2014, 07:30 PM
How does the top bar attach to the master? Does it have remote reservoirs?

chevynut
02-02-2014, 07:43 AM
The top "bar" is a small hollow reservoir that came with the master cylinder. It's actually made of 1" square aluminum tubing. The black rubber bushings are the seals and it has some tubes that go down into it. I welded the AN fittings onto it because it only had clamped hose connections and I didn't like them. The long hose in the pic is the one that goes to the remote reservoir I made. It sits right next to and above the MC. Here's the reservoir....it bolts to the cowl. I put a level sensor and a sight glass on it, and welded an AN fitting to the bottom. I hope to connect the level sensor to the Dakota Digital VHX gauges.

291029112912

NickP
02-02-2014, 08:44 AM
I wonder whos master cyl that is. Do you think it's theirs or do they purchase? Length from flange face to end? So the 1" Square tube has 3 bungs that simply slip into the three orifices with a rubber seal, right? OH, stroke depth?

Rick_L
02-02-2014, 09:11 AM
Nick, that's the part that leaks that I mentioned on the other board. It has to be "just right" to not leak. I think all that stuff is made by/for ABS, it's what's different about their system compared to the Bosch OEM Buick system that it's based on.

NickP
02-02-2014, 09:23 AM
What year and model Buick is that Rick? Can it be adapted to other uses? Again folks, many thanks for your replies.

chevynut
02-02-2014, 10:37 AM
Rick, the rubber bushings like that are used on many other master cylinders, including the C4 Corvette. Any master cylinder that has a metal body and a plastic reservoir uses some rubber bushing or o-ring. I don't know why they would leak...the one on my Silverado doesn't. I thought their stuff was some euro car application they based it off of. I've never seen anything like this on a Buick.

Nick, the top block came on my master cylinder, which is from ABS Power Brake. It was already assembled to the MC.

Rick_L
02-02-2014, 11:53 AM
I think the problem is that the ABS reservoir is bulky and is aluminum, the mass and center of gravity make it rock on the master cylinder. A plastic one is a lot lighter. The one I saw and helped repair seemed to fit loose on the rubber bushings with the original set of ABS parts. Fit better with the second set. As I recall the reservoir and bushings were replaced.

chevynut
02-02-2014, 11:59 AM
Nick, look here:

http://www.abspowerbrake.com/ehpm.html

Second pic down P/N 10-57

chevynut
02-02-2014, 12:03 PM
The one I saw and helped repair seemed to fit loose on the rubber bushings with the original set of ABS parts. Fit better with the second set. As I recall the reservoir and bushings were replaced.

Rick, where did you get the replacement bushing seals? I wonder if they can be bought from a local store, rather than from ABS PB, just for future reference.

Rick_L
02-02-2014, 12:33 PM
The friend I was helping got all the parts from ABS. You're probably aware of their customer service - they will come through but you may have to call several times and be patient.

The parts could quite likely be obtained from an auto supply, but what to ask for?

Back to your original question about the leak - since the 2nd round of parts fixed the leak, I think they just didn't fit right the first time. The reservoir could be wiggled on the master cylinder quite easily originally, a tighter fit after replacing the parts. So I think it's as much their parts as the extra weight of the aluminum.

The unit he has is the original version of the 10-56. Difference is that it's a rectangular reservoir rather than the goofy peanut shape.

Olderthandirt
02-02-2014, 07:50 PM
87 Buick Grand Nationals & My 88 Reatta had an electric booster pump below the MC.

chevynut
02-02-2014, 08:33 PM
87 Buick Grand Nationals & My 88 Reatta had an electric booster pump below the MC.

http://www.kirbanperformance.com/product_images/7021_lg.jpg

NickP
02-02-2014, 09:50 PM
Where would one find that whole setup?

Rick_L
02-03-2014, 06:41 PM
If I wanted an OEM Buick setup, I'd first try rockauto.com to see if they listed it.

The other thing I would do is check the Turbo Buick forums. There is more than one, don't remember how many, and it's been a while. I used to go to them for info on 200-4R transmissions when I put one of those iny Nova.

They won't talk encouragingly on the reliability of the Bosch system. Seems the preferred system on a Turbo Buick is a hydroboost. To me the only reason to choose the Bosch (or ABS) system over a hydroboost is if you don't have power steering or you have some bling reason for the ABS system. No power steering was the reason my friend chose it, plus he had a BBC with tall valve covers and no vacuum, so he couldn't run a decent vacuum booster.

chevynut
02-03-2014, 07:44 PM
My reason for choosing the ABS system was the hydroboost didn't fit where I wanted to put it. The ABS electric booster is 4" shorter. I hope I don't have issues with it, or I don't know what I'll replace it with.

chevynut
02-03-2014, 07:49 PM
http://www.ebay.com/itm/85-87-Regal-T-Type-Rebuilt-Powermaster-Brake-Unit-125-Refundable-Core-Charge-/350818286765?_trksid=p2054897.l4275

NickP
02-03-2014, 07:52 PM
This build is a 1977 Bronco. A one off or who knows. As you most likely are aware, a Bronco has little room to begin with Rick. Wanting a clean and smooth firewall, we have opted to hide those items under the dash. I just received the latest Wilwood front and rear brakes for it – very trick.
Presently, I have taken a Kugel 90° under dash unit, cut it apart and changed the direction from pointing at the passenger side to the driver side. I only have about 9” from the end of the MC adaptor plate to the inside of the cab. It’s been a challenge. I need a system that will give the needed pedal feel and operate the brakes. Wilwood has indicated that a simple 1” MC with no booster is all that’s required as long as long as the ratio is correct. I have sufficient room under the body in multiple places to place the pump and reservoir but using the ABC unit requires a MC that is just too long. It’s an arduous process but a lot of fun getting to find new and interesting parts to put together.
I looked up where that pic was from, one of the Buick places and it’s about ½ the price of the ABC unit but the MC is very tall with the reservoir attached. I may just try to purchase only the MC to determine how it all functions and how it can be modified to work if it can at all. I have to keep in mind that repairs that happen down the road need to have easy part availability for the customer. There’s a lot to remember when building something for another person.

NickP
02-04-2014, 09:27 AM
I think the problem is that the ABS reservoir is bulky and is aluminum, the mass and center of gravity make it rock on the master cylinder. A plastic one is a lot lighter. The one I saw and helped repair seemed to fit loose on the rubber bushings with the original set of ABS parts. Fit better with the second set. As I recall the reservoir and bushings were replaced.

Those bushing, are they rubber or some other product that is not adversely affected by the constant emersion in brake fluid?

Rick_L
02-04-2014, 08:15 PM
I'm fairly sure the bushings are EPDM rubber, the usual choice for brake fluid service.

NickP
02-09-2014, 10:05 AM
The top "bar" is a small hollow reservoir that came with the master cylinder. It's actually made of 1" square aluminum tubing. The black rubber bushings are the seals and it has some tubes that go down into it. I welded the AN fittings onto it because it only had clamped hose connections and I didn't like them. The long hose in the pic is the one that goes to the remote reservoir I made. It sits right next to and above the MC. Here's the reservoir....it bolts to the cowl. I put a level sensor and a sight glass on it, and welded an AN fitting to the bottom. I hope to connect the level sensor to the Dakota Digital VHX gauges.

291029112912

What size line from the tank to the master, #3? Also, reservoir capacity, does it match any particular requirement? I have a couple of reservoirs but they only hold four ounces on one set and six on the other set. How much fluid?

chevynut
02-09-2014, 11:18 AM
I used 6AN lines from the tank to the MC top, and 6AM from the top to the pump. That's the size ABS sent with the kit. I just changed it to use AN fittings.

I don't remember what reservoir capacity I used. It's buried under my fender right now. I think it's between a pint and a quart. It gets filled about 2/3 to 3/4 of the way, so you can see the level on the sight glass. The sensor trips quite a bit lower than that.