Hot Rods Brake Help

I am trying to identify the system design for these brakes. I have sent pictures to many experts and no one can identify the system design. At times the pedal becomes extremely hard, no assist. I expect its a faulty pressure accumulator (black sphere). Has anyone seen this type of system before? Thanks!

 

That's a GM master cylinder, it appears with the pressure accumulator it's a hydro-boost system. Looks to be a big mess. With a bunch of different unions. That's kinda scary.


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It is scary! I get what you're saying but it does Not have power steering so how can it be a hydro boost system?

 

Where do the hydraulic hoses go?

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Those hydraulic hoses, what are they for then. That is some weird stuff for right there


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They go to the M/C and prop valve. See pic. The black sphere is the accumulator. I have only ever seen these on high end cars like Mercedes and Maserati (and the occasional Buick).

 

Electric power brake booster.

 

The reservoir is in the trunk (top pic). The actual M/C is under the floor so the hoses run from the reservoir to the M/C. I just don't know what the silver can (cylinder) is under the reservoir.

 

The reservoir can be anywhere, as long as it is bled, and has no leaks.

The silver can is the electro-hydraulic pump that provides boost pressure.

 

Wow, thanks gimpyshotrods!!!!! You win! I don't immediately see any electrical wiring, but maybe I am just not seeing it. That "silver can" I referred to might be the electric motor. I need to crawl up in there and look. You have helped a ton! I have read that these accumulators are notorious for going bad. I'm glad I bought a spare!

 

Thanks again gimpy!!! Have you used or installed this system in the past? What else should I know about it?

 

There should be an electrical connector on it somewhere. Feel around.

 

You are going to hate to hear this. No, I have not installed them.

I have removed two systems that had failed, at the pump. The owners balked at the cost of the repair. At the time, a replacement pump was almost $1000.00.

 

I have a 1988 Buick Reatta and your system, though not exactly the same, reminds me of the Reatta ABS system. If you go to reattaowner.com forum you will find a troubleshooting procedure that might help you out. There are also very knowledgeable people at the Buick Reatta AACA forum. I can mention a few other Buick sites but it all becomes redundant. I suggest you check it out and you might glean some information that you can use to help solve your problem.

 

Well, actually that does help, if not scary. It is par for the course with this car...nothing is as it seems. At least I know what I'm in for. Thanks again. Wish you were closer. I'd have you replace it too. I already backed into someone when it failed. Ouch!

 

Will do, Thanks!

 

Wow. Just did my research and what a hot mess! What options do I have? Hydro boost is a no go....no P/S. Why not just manual brakes? My Nova had them and never an issue.

 

I'd pull that system out of there quicker than you can say Rube Goldberg !
Brakes should be simple and redundant with as few fail points as possible. Manual...got to be better than what you have now and parking lot safe too.

 

No issues whatsoever with manual brakes. As long as the pedal ratio is good, and the master cylinder bore is appropriate for the calipers and/or wheel cylinders, it's all good.

Do you know what specific brakes are on all 4-corners?

 

It does not surprise me that you've removed two systems. I'm not a fan.

 

Thank you all! Great help from everyone.

 

If you can fenagle the space, HAMBer @55willys sells remote boosters that run off of engine vacuum, provided that you have enough engine vacuum. They don't have a specific home-location, as long as the are plumbed and bled properly, and, of course, have no leaks.

http://www.jalopyjournal.com/forum/threads/remote-mounted-hydro-vac-units.1002886/

Not sure you have the space. That thing is pretty busy under there. It could go in the trunk, I suppose.

 

1) overall length 13"
2) length of center 4.80"
3) length of end 4.09"
4) diameter of body 5.50"
5) centerline to side of plumbing 4.13"

Or:

1) overall length 15.11"
2) body length 9.84"
3) end length 5.27"
4) body diameter 7"
5) centerline to side of plumbing 4.48"

 

I'd be thinking manual brake conversion.

 

IF that does not require cutting up a finished car, to fix the pedal ratio.

 

Yes. Looking back to post 15, he will be mixing up some paint to fix some damage anyways.

 

I had to pull the tank to install the in-tank pump for EFI so I had it repaired and repainted a few weeks ago. But I do have a lot of paint left over.

 

Good attitude, @Wes Rager! I like that.

 

If you whip up a little diagram of the brake pedal, showing how it is configured, including these dimensions:

Pedal pad center to pivot center.
Pushrod pin (on pedal arm) to pivot center.

...we can figure out the ratio, and what changes would need to be made, in the least intrusive way possible.

 

Thanks for your help! I will get the dimensions in the next few days.