Calling all Teves brake system experts!

Topic: Calling all Teves brake system experts! (Read 4143 times) previous topic - next topic

Calling all Teves brake system experts!

August 18, 2010, 10:10:25 AM

My thread on NATO got kinda hijacked so I figured I would start one here too. I just picked up an 87 TC with an extremely hard brake pedal. It is nearly impossible to stop.

The first thing I noticed is that there was an unplugged relay under the vacuum tree that goes to the pump motor. I also noticed that the line coming out of the reservoir was clamped off with a pair of vise grips. The fluid was also a little low. I topped off the fluid, plugged the relay in and removed the vise grips from the line. The pump motor now runs when the ignition is turned on but doesn't seem to build any pressure because it runs continually and the pedal never gets softer.

Is this an indication of a ruptured accumulator? Why would the previous owner have clamped the line off? I can find no leaks with the vise grips removed.

I used the article at NATO for troubleshooting. http://www.turbotbird.com/techinfo/TEVES%20II%20ELECTRO-HYDRAULIC%20BRAKING%20SYSTEM%2087-88%20TCs.htm

Here are some pictures of the unplugged relay and the clamped line location.

Calling all Teves brake system experts!

Reply #1 – August 18, 2010, 11:09:21 AM

Well, the pump running continuously and not building pressure,
sure sounds like a bad accumulator to me .
I hjve no idea why the vice grips would have been there

Calling all Teves brake system experts!

Reply #2 – August 18, 2010, 11:11:52 AM

looks like they were there so it would build pressure.

Calling all Teves brake system experts!

Reply #3 – August 18, 2010, 11:13:16 AM

I just read your other post , If you have another accumulator to try, it only takes about a minute to swap one out .

Calling all Teves brake system experts!

Reply #4 – August 18, 2010, 11:33:45 AM

Yeah, I have a whole extra power brake assembly the guy gave me. He hadn't even opened it from whoever he bought it from on ebay.

Calling all Teves brake system experts!

Reply #5 – August 18, 2010, 11:43:04 AM

I think you got a great score then :D

Calling all Teves brake system experts!

Reply #6 – August 18, 2010, 11:57:30 AM

I agree, a pretty good deal. Do you think I can unscrew this accumulator safely? Like there shouldn't be any pressure in it, correct? In either one for that matter.

Calling all Teves brake system experts!

Reply #7 – August 18, 2010, 12:03:11 PM

There shouldn't be any pressure in either one , you should have no problem .

I had just replaced my accumulator in my Mark VII when I sold it ..

I will try and remember where I got it , and post you a link

Calling all Teves brake system experts!

Reply #8 – August 18, 2010, 12:18:22 PM

I remember reading back when I had my Supercoupe that a place called Prior sold them but its been a few years now.

Thanks for all your help. I will post up results.

Calling all Teves brake system experts!

Reply #9 – August 18, 2010, 12:54:41 PM

I swapped out the accumulator balls but nothing changed. The pump still just runs continually but doesn't seem to build pressure. I let it run for about 45 seconds then pushed the pedal and it felt the same. How long does it take to charge up a fully charge it up? Maybe the pump is weak or another bad accumulator?

Calling all Teves brake system experts!

Reply #10 – August 18, 2010, 03:02:44 PM

Its should only take about 30 seconds to get pressure .

Calling all Teves brake system experts!

Reply #11 – August 19, 2010, 04:37:42 PM

Ok, so my pump is running when the ignition is on but it never stops, so I assume it never reaches the needed pressure because the brake pedal never gets softer. So I guess accumulator #2 is bad also, which sucks.

Now from my research, I can get an accumulator from a TC, Mark 7, or SC and possible some Buicks. Is this correct?

Calling all Teves brake system experts!

Reply #12 – August 19, 2010, 04:49:50 PM

how are you sure its the acc. ball and not something in the pump or something else in the teves unit?
Since you have a whole other unit, why not swap it all out and see what happens?

Calling all Teves brake system experts!

Reply #13 – August 19, 2010, 07:08:39 PM

Quote from: Loaded87IROC;332654

Ok, so my pump is running when the ignition is on but it never stops, so I assume it never reaches the needed pressure because the brake pedal never gets softer. So I guess accumulator #2 is bad also, which sucks.

Now from my research, I can get an accumulator from a TC, Mark 7, or SC and possible some Buicks. Is this correct?

Some Saabs, Mopar minivans , Cadillacs, Merker Scorpio and others the important thing is that the threaded nipples match up.

I do agree with BogusSVO you should try swapping out the other unit before buying any parts

Calling all Teves brake system experts!

Reply #14 – August 20, 2010, 01:32:55 PM

Hi all.

The accumulator is just a small fluid tank with an air (nitrogen actually) bladder inside to give the system some reserve pressure. When it goes bad you get a very quick cycle pump, and no assist after 1 pedal stroke. You lose capacity since you can't compress a liquid, thus the compressible bladder. The accumulator doesn't do anything else and has no moving or mystical parts in it. (Works just like the water tank on a well system in a house.)

It does hold up to 2000psi when loaded, so just make sure to pump down any pedal assist and leave the key off when removing it and you'll be fine. The factory always said 50 pedal strokes, but experience showed that you just want a rock hard pedal.