1990 Brake Issue

[KDirk]

Regarding the label, my good 88 has a factory original part and has the yellow label on the side, not the top. All the cars I've parted (two 89's and a 90 thus far, and the 88 I bought to part) had the side label, and no made in Germany sticker (indicating they were factory parts most likely). I think the Made in Germany sticker was added when the part was transferred from GM SPO to AC Delco distribution, but definitely after the end of production of Reattas as I've not seen an original on car with it. Heck, in 88 we still had West and East Germany.

 

The only version I've seen with the round label around the "bung" on top is the Jaguar part.  I suspect Jaguar had a different label applied to their version of the ATE accumulator than GM, Saab and others for whatever reason. In any case the one Flajunkie has posted looks original. 

 

 

 

[Barney Eaton]

The photo in post #36 is a good example for the fit of an original part... note that there is at least 1/8 in clearance between the accumulator and the cross brace.  

Many have commented that some of the available replacements are taller and the cross brace must be "shimmed" with washers to keep the accumulator and brace from rubbing.

 

Until recently, when replacements of unknown DNA started appearing, all the accumulators were made in Germany by Teves or their supplier/division Ato

There were no Delco accumulators, GM put the German manufactured parts in Delco boxes with the GM part number but all came from the above supplier(s) in Germany

[Guest flajunkie]

The measurements for the original are about 3.5 inches wide by 4 inches tall.

 

The aftermarket on eBay is 4 inches wide by 6 inches tall. That is way to tall and really too wide.

 

And people are using these on our cars?

 

 

[Digger914]

3 hours ago, flajunkie said:

The measurements for the original are about 3.5 inches wide by 4 inches tall.

 

The aftermarket on eBay is 4 inches wide by 6 inches tall. That is way to tall and really too wide.

 

And people are using these on our cars?

 

 

eBay can be a strange place to buy things and I saw this thing being sold as the delco 255---- for $100 more than the going wabco price. Go Figure

[Guest flajunkie]

I've just ordered an accumulator from an eBay vendor I trust.

 

I'll let all of you know how it goes.

[Blue90]

Missing from the discussion here is any use of used accumulators.  

I know there's no way to measure the charge left but they're easy to change and cheap in pick n pulls.

I have five in my basement; two look brand new.  

BTW, they all have a yellow label on the side and no white Made in Germany label.

S.

[DAVES89]

8 hours ago, Retired w/Reatta said:

Missing from the discussion here is any use of used accumulators.  

I know there's no way to measure the charge left but they're easy to change and cheap in pick n pulls.

I have five in my basement; two look brand new.  

BTW, they all have a yellow label on the side and no white Made in Germany label.

S.

See post 18 from Kevin [kdirk].

 

Edited August 31, 2016 by DAVES89 (see edit history)

[Barney Eaton]

i have considered building a tester for the Teves pump, pressure switch and accumulator.  It is low on the priority list as I do not own a Reatta with the system.

My main computer is in the computer hospital or I would make a sketch........ imagine this

Take a pump assembly and mount it on some sort of base.

Supply 12 v to it via a used harness.....have an on/off switch to stop the 12V supply

It would need a graduated fluid container that would feed brake fluid to the pump input

The line coming out of the pump to the booster would need......(1) a "T" fitting for a 3000 psi pressure gage   (2) a on/off (open/close) valve and the output would

empty into the fluid container.

This would allow you to.......

(1) test the pressure switch for the pressure when they would turn on and off the pump.

(2) the graduated fluid container would tell you how much fluid was being stored in the accumulator, which would allow them to be graded from bad to good

(3) with a timer you could also grade the condition of the pump

All of this would fit on a 12 in square base and would be self contained  

[waltmail]

8 hours ago, Barney Eaton said:

i have considered building a tester for the Teves pump, pressure switch and accumulator.  It is low on the priority list as I do not own a Reatta with the system.

My main computer is in the computer hospital or I would make a sketch........ imagine this

Take a pump assembly and mount it on some sort of base.

Supply 12 v to it via a used harness.....have an on/off switch to stop the 12V supply

It would need a graduated fluid container that would feed brake fluid to the pump input

The line coming out of the pump to the booster would need......(1) a "T" fitting for a 3000 psi pressure gage   (2) a on/off (open/close) valve and the output would

empty into the fluid container.

This would allow you to.......

(1) test the pressure switch for the pressure when they would turn on and off the pump.

(2) the graduated fluid container would tell you how much fluid was being stored in the accumulator, which would allow them to be graded from bad to good

(3) with a timer you could also grade the condition of the pump

All of this would fit on a 12 in square base and would be self contained  

Would this be for testing  junkyard units?

[Blue90]

On August 7, 2016 at 6:55 PM, KDirk said:

The other possibility if you are so inclined and have a large salvage yard nearby is to find a good used accumulator. Yes, it is a crap shoot and they are not terribly common but if you have a large U-pick or similar you may find one. Keep in mind that this is a short term solution at best as I'd not want to trust a used unit for very long. If you happen across a car with an intact Teves system, pulling the entire pump/reservoir/accumulator unit is highly recommended as you will then have all the major components less the wheel sensors.

 

I agree completely with Kevin.  The reason I brought it up is because of the scarcity and price of new ones that fit; it is another option.

I also wonder how many new Reatta owners immediately change out their accumulators; I imagine very few.  So in essence we're all driving around with used accumulators, and of unknown age.

 

It appears as if we have two different conversations going on here.

 

To flajunkie: The image in #36 shows an overfilled brake fluid reservoir.

[Blue90]

One of the keys to safe brakes in the 1988 to 1990 Reattas, I believe, is to do regular brake tests.  The results will vary from car to car (read accumulator to accumulator)  which is why it is important to do them regularly to get to know your car's eccentricities. 

If your brakes are working fine, regular tests will tell you BEFORE something catastrophic happens, as in the start of this thread.

I also live in a very humid climate and I flush my brake fluid every spring.

S.

[Guest flajunkie]

13 hours ago, Retired w/Reatta said:

To flajunkie: The image in #36 shows an overfilled brake fluid reservoir.

 

I was wondering if anyone would notice that. I checked the level before testing and it was actually lower than the full mark. The accumulator has been sitting there for days without any usage, so I am puzzled as to why the level increased.

 

Does anyone out there think there may be a different issue here, like a blockage at the accumulator? I don't really trust the local Buick dealer when they said they did the brake fluid change...as in did they bleed the system properly? It has been almost a year since they did it.

 

Thoughts?

[Guest flajunkie]

3 hours ago, 89RedSlate said:

A flat coffee stirrer from your local Convenience store, taped to vacuum hose or aquarium air line (my clear choice) then run to a ShopVac. The flat coffee stirrer slips easily under the float, and to the bottom. Way safer than risking removal of the hose and breaking a brittle plastic nipple.

 

 

 

What does this mean? Is it part of the bleeding process?

[Guest flajunkie]

Well, I made the change. After installing it, it took about a minute to pump up. After the pump stopped, I had her apply the brakes and within two pumps, the motor came back on, but for only a short time. It is doing this after every second pump of the brakes. I know the brake fluid level is low, but that should not affect the accumulator pressure.

 

Does this sound normal? Here's a video of it I posted on YouTube.

 

 

I'll post the install pics next.

[Guest flajunkie]

Installing the accumulator:

 

1) Clean off the area around the screw threads/base.

2) Find an allen wrench that fits the top.

3) Remove the two 13mm nuts that secures the brace. Be careful not to lose the clip for the cowl thumbnut.

4) Remove the accumulator.

5) Carefully clean up the thread area. CAREFULLY.

6) Lube the O-ring on the new unit with some brake fluid.

7) Install the new unit.

8) Hand tighten.

9) Use an open end wrench to snug up the base. (I didn't do this...I tightened by hand and could not remove it once the O-ring sealed.)

10) Reinstall the brace.

11) Turn on the key and allow the new unit to fill up.

 

[Guest flajunkie]

Fordrodsteven may have had it right before...maybe it isn't an accumulator problem.

[Guest flajunkie]

52 minutes ago, 89RedSlate said:

I would think- the larger the bulb, the more fluid capacity it has, so the pump isn't designed to keep that higher volume of fluid at the switch's set level, so it kicks on more. Does the new units' pre charge match OEM? Key off, 25-30 full, slow, complete pumps of pedal. Fill reservoir to "FULL" triangle. Key on, after pump stops, level should be 1/2" below triangle. 3-4 full pedal pumps to make pump run is average. Your switch appears new- is it? With system energized (accumulator full, pump stopped) can you hold the pedal down, without making the pump run again? (verifying no leaks)

 

A strap-type oil filter wrench works great for the accumulator (what I used)

 

 

If the accumulator works correctly, the pump should raise the pressure to over 2000 PSI and you should get more than two pumps before it kicks on again. I have asked the vendor what the precharge is. And no, I don't have a new switch; the car just looks new. I'll check for leaks in a bit.

 

Just checked. Holding the pedal down did not result in the pump starting.

 

But what was interesting, when the key was turned on again after it had been off for 30 minutes, the accumulator pump ran for over a minute, like it was charging a new accumulator all over again. What do you make of that?

Edited September 5, 2016 by flajunkie (see edit history)

[Guest flajunkie]

6 minutes ago, 89RedSlate said:

 

Yes, if the pump is working correctly. If the volume of the accumulators' fluid chamber is larger than OEM design, the pump would shut off prematurely, but then need to run more often, to keep that larger volume at set point. Maybe the pressure switch is weak? The only definitive way to test all of this- is with an in-line gauge, between master cylinder and accumulator.

 

I'm probably bass akwards here. There are many more Members here way more versed in the operation of the TEVES brake system than I am.

 

The precharge is 1100PSI - 80 BAR. If the pump pumps to 2500 psi, then it should work properly regardless of the size of the bulb. I think you may be on to something about the pressure switch. If it stops short, the system would respond just as it is now. Wonder where I can get one of them?

Edited September 5, 2016 by flajunkie (see edit history)

[Digger914]

2 hours ago, flajunkie said:

Well, I made the change. After installing it, it took about a minute to pump up. After the pump stopped, I had her apply the brakes and within two pumps, the motor came back on, but for only a short time. It is doing this after every second pump of the brakes. I know the brake fluid level is low, but that should not affect the accumulator pressure.

 

Does this sound normal? Here's a video of it I posted on YouTube.

 

 

I'll post the install pics next.

Everybody has their own idea of what a light tap to the brake peddle is, but it's light taps that simulate normal braking. If the peddle is being pushed all the way to stop like you've run it to the floor for a panic stop and from the squeaks on the video I'm guessing that's what was done, this sounds right.

Also looks like a pretty good fit for the accumulator,

[2seater]

I see a comment was just made about what constitutes a "pump". I have never had my system pass all the tests, primarily due to that same question. I have the larger Spinning Wheels accumulator, and I have verified the on and off brake pressures are correct. I get two pumps at most  and the pump will run for a short time and off. The brakes feel more solid than they ever have and I have had the car for 22+ years. I think the brake tests are a good practice to follow, and keep a record of your own vehicle and how it performs. I do not take the stated numbers as gospel.

[Guest flajunkie]

I agree with the above two replys.

 

I have a question for all of you with this system.

 

Go outside (sometime after the car has been out of use for over an hour) and pop the hood. Stick the key in the ignition and while standing outside, turn it to ON, not Start.

 

How long does the pump run or does it?

 

 

[Digger914]

Expect several time answers for this question. This is how mine works, if I haven't started the car for several days the pump seems to run forever, but it's a minute or less. When I turn the car off after driving and go back to it in an hour the pump will usually run for a few to several seconds. When I turn the key on let the pump run till it stops and turn the key back on in an hour or so my pump will sometimes run, the abs light is off in the first couple seconds and the pump is always off before the seat belt warning light goes out.

 

Just in case, two part numbers for the pressure switch, the three over two blade is 25530882, the five pin in the dice pattern is 25533700, one is for the 89, the other is for the 90, same switch, different plug connectors, I don't know why. 

 

 

[Guest flajunkie]

OK, back from the garage.

 

The fluid was really dark, so I had them do a complete brake fluid change.

 

After bleeding the brakes, they work fine.

 

More importantly, the ABS light is now off.

 

I listened to the pump run for almost a minute when the key was turned on. Seems to be the 'normal' for this car.

 

I'm not going to completely consider this closed yet, but it seems to be well on its way!

[Guest Kingsley]

1 hour ago, flajunkie said:

OK, back from the garage.

 

The fluid was really dark, so I had them do a complete brake fluid change.

 

After bleeding the brakes, they work fine.

 

More importantly, the ABS light is now off.

 

I listened to the pump run for almost a minute when the key was turned on. Seems to be the 'normal' for this car.

 

I'm not going to completely consider this closed yet, but it seems to be well on its way!

 

The physical dimensions of the various accumulators that are in play now have been fairly well documented.  In terms of volumetric capacities, the OE has a capacity of 15 cubic inches and the Hydac accumulator that has been mentioned here often has a capacity of 20 cubic inches.  These figures are imprinted on the side of the accumulator.

 

I may have overlooked it in previous posts but does the one you are now using have a volume figure imprinted on it?  Might be shown in fractions of a liter.

 

In any event, glad to see  that it is working well now and it does appear to fit nicely.

 

Kingsley Baker

Reatta Specialty Parts

[Barney Eaton]

The unit looks pretty good and the performance, per the video, also seems acceptable.

As Kingsley noted there is probably a difference in volume, not sure if the numbers quoted are total or the difference in the operating range. 

In one of the earlier post a 1000# pre-charge was mentioned....the factory unit is 750# minimum when new,  no mention is made of the max pre-charge.

This pre-charge also seems to have an affect on the fluid level drop. ...it is only dropping slightly from the time the pressure switch turns off the pump motor to the level/pressure where the pump turns back on.

I would be interested in the level drop from a complete discharge to fully charged.

[Guest flajunkie]

Well, hells-bells.

 

Turned the key to on this morning and the pump almost ran two minutes.

 

Not only that, the ABS light is back on.

[Digger914]

If the ABS light is back on and this is a game your ABS likes to play, I would start by giving the relay a gentle love tap. Crud in the ring teeth or a dirty or loose connect anywhere along the line can do the same thing, so move the car one half tire rotation so you get new sensor ring location and try again before you tap the relay and start checking wire connections.

 

2 mm volume is 25% more fluid than 1.5 mm and the pump only moves so much fluid per second, so a longer charge time to pressurize and re pressurize is to be expected. On the plus side, you have a larger pressure reserve and the pump won't run as often.

 

[Guest flajunkie]

36 minutes ago, Digger914 said:

If the ABS light is back on and this is a game your ABS likes to play, I would start by giving the relay a gentle love tap. Crud in the ring teeth or a dirty or loose connect anywhere along the line can do the same thing, so move the car one half tire rotation so you get new sensor ring location and try again before you tap the relay and start checking wire connections.

 

2 mm volume is 25% more fluid than 1.5 mm and the pump only moves so much fluid per second, so a longer charge time to pressurize and re pressurize is to be expected. On the plus side, you have a larger pressure reserve and the pump won't run as often.

 

 

I'll start playing with the ABS next. Thanks.

 

As to the accumulator, the pump starts almost immediately after the start of the second press of the brake pedal. I wonder if all these Teves systems have varying operational parameters.

 

[DAVES89]

I would just swap out the relay with a known good one. The relay you probably have is original and may have failed.

 BTW you need to list the year of your car on the signature line. We are now on page 3 and who can remember what year car you have.

 Anyway the 1988/89 Reatta has the ABS relay on the fire wall. On the '90 I believe it is in the console on the driver's side. It is probably the relay. I wouldn't think it is either the exciter ring or the ABS lead as you probably haven't really driven the car from the other day when you put the accumulator in. To be sure you could disconnect the battery lead for about 10 minutes. I believe that would clear brake codes.

 In regards to why the pump is running for 2 minutes someone smarter then me is going to have to address that one. It could be that you have a larger capacity accumulator, but then what I would do to test that is to turn the key to "on" [this is after sitting overnight] and time the pump from when it starts to when it turns off. Then pump the brakes until the pump starts to run, then time it again until it turns off. Keep track of the pumps.

 The most important thing is that the pump starts, runs, and then turns off. This is good.

 If it doesn't run you have no real braking power, if the pump runs all the time without shutting off you will burn up the pump. 

 

Edited September 7, 2016 by DAVES89 (see edit history)

[Guest flajunkie]

44 minutes ago, DAVES89 said:

I would just swap out the relay with a known good one. The relay you probably have is original and may have failed.

 BTW you need to list the year of your car on the signature line. We are now on page 3 and who can remember what year car you have.

 Anyway the 1988/89 Reatta has the ABS relay on the fire wall. On the '90 I believe it is in the console on the driver's side. It is probably the relay. I wouldn't think it is either the exciter ring or the ABS lead as you probably haven't really driven the car from the other day when you put the accumulator in. To be sure you could disconnect the battery lead for about 10 minutes. I believe that would clear brake codes.

 In regards to why the pump is running for 2 minutes someone smarter then me is going to have to address that one. It could be that you have a larger capacity accumulator, but then what I would do to test that is to turn the key to "on" [this is after sitting overnight] and time the pump from when it starts to when it turns off. Then pump the brakes until the pump starts to run, then time it again until it turns off. Keep track of the pumps.

 The most important thing is that the pump starts, runs, and then turns off. This is good.

 If it doesn't run you have no real braking power, if the pump runs all the time without shutting off you will burn up the pump. 

 

 

My Significant Other just called me and said when she came out of her appointment, the car started OK and the ABS light is now off.

 

I agree, this could be a relay.

 

The thing that troubles me is that this light also goes on if the pressure in the system is down below 2000PSI.

 

From an autozone writeup on a similar GM Teves car:

 

PRESSURE SWITCH

The pressure switch is mounted on the pump/motor assembly and serves 2 major functions, controlling the pump/motor and providing low pressure warning to the Electronic Brake Control Module (EBCM).

The switch will allow the pump/motor to run when system pressure drops below approximately 2030 psi (14,000 kPa) and will shut the pump/motor off when pressure in the accumulator is approximately 2610 psi (18,000 kPa). Should pressure within the accumulator drop below approximately 1500 psi (10,300 kPa), internal switches will both signal the EBCM and turn on the red BRAKE warning lamp. If the system re-pressurizes and reaches at least 1900 psi (13,100 kPa), the switches will reset.

 

Here is another good write up.

[Digger914]

Operational parameters of the system don't vary, how hard our feet hit the brake peddle and how long they stay on it varies from person to person.  Dealerships were required to buy the Teves test set, the pressure bleed gizmo was optional. We use our feet to test the system so our perception of results vary from person and because some pump to bleed, some gravity bleed and some vacuum bleed the fronts, we don't all and always get a good bleed of the valve pack, so after 25 years I would imagine that everyone of these works a little bit different.  

 

Using your foot in place of the tester, give the brake peddle your best and fastest nerves foot tap, just enough to flicker the brake lights, how many taps does it take to activate the pump? and how many more to light the ABS light?

 

 

[Guest flajunkie]

I haven't done the tap test yet. I did let the car sit and checked it a few days later. The pump runs about a minute or so and stops. Let it sit turned off for a few minutes and it pumps up in less than 10 seconds. The ABS light is still on.

[Guest flajunkie]

Update:

 

Today, I used a paper clip to check for ABS codes. The light did not flash, so I assume there were no stored codes. I read here you need to check them before the light can reset. By the way, the red brake light turned off just after the car started.

 

My lady took the car to an appointment. The ABS light was on all the way there. She tried turning the car off/on at a street light but the light stayed on.

 

After her appointment, about two hours later, she started the car and the ABS light went off immediately after engine start. She drove back home stopping twice for errands and the light always turned off after engine start.

 

If I was a betting person, I'd bet it is back on in the morning after the car sits all night and the accumulator leaks down.

 

Does anyone have any ideas? It is obvious the fuses are OK and the controller board must work, and the sensors are probably OK. Maybe the ECBM has some intermittent power issue? Or maybe the accumulator leaks down because there is some small leak in the braking system?

 

Thoughts?

[Guest flajunkie]

Just now, 89RedSlate said:

First of all- is this the original 26 year old Accumulator? Under hood temperatures where you are, coupled with (probably) running the AC, and the lower air flow of stop-and-go traffic, and then heat soaking when shut off- could all cause an older Accumulator to increase it's pre charge, thereby temporarily satisfying the pressure switch enough to cause normal operation.

 

The next step I would perform is that when the yellow ABS light is off- immediately attempt to read the ABS codes, following

instructions found HERE.

 

If the ABS stays on, it is most likely the Accumulator. A quick way to check the thermal idea- get a blue freezer pack, set it on

top of the accumulator. Give it time to cool, even wrap a damp rag around the whole unit, to chill it. After about an hour- if the

ABS is still on while started & driving (cooler removed) then the theory of a discharged Accumulator is more likely.

 

It's the new accumulator. I didn't think about reading the codes with the light off. I'll see if I can do that. Thanks.

[Guest flajunkie]

OK! Got the codes, but not sure about them.

 

Jumper in Key on:

ABS flashes 2 times then pauses black.

ABS flashes 7 times remains solid ABS.

 

Remove and replace jumper:

ABS flashes 9 times then pauses black.

ABS flashes 10 times remains solid ABS.

 

Remove and replace jumper:

ABS solid.

 

So 26 and 99???

 

26: Rear inlet valve

99: Isn't on the table

 

Now what?

 

As to the accumulator, the vendor claims "The Nitrogen precharge pressure on the new accumulator is 1,160 PSI (80 BAR)."

 

 

[Digger914]

Dirty/sticky switch possible, relay contact most likely. Pressure to turn off the pump is higher than pressure to run ABS, as your pump turns off I lean towards the ABS relay first, dirty sensor rings or connect to sensor cables second, dirty contact at pressure switch more likely on lower mileage car than bad switch, but pull plug connect and look for moisture from brake fluid just in case, otherwise plug and re-plug connector to switch several times to get fresh clean connect. Same for relays.

 

Was writing this when you posted codes, reseat plug connects to valve pack on brake assy and ABS controller several times and try again.

[Guest flajunkie]

From another TEVES site:

 

26 Rear Inlet Valve (Disconnect 7 pin connector on Valve Block, measure resistance Pin 7-3, 5-8 ohms service harness, other reading replace valve block).

 

99 Electronic Controller (Clear memory Read codes … get 11 or 99 replace Electronic Controller)

 

"The types of codes present here will be basic system faults which will cause the Amber Anti-Lock Warning Light to remain lit even after 4 seconds have elapsed on the Self-Test...Two things to be aware of though. One, if the first code received is in the 20’s, service the indicated fault. No other codes can be outputted to the code reader if a 20’s fault exists. After servicing the 20’s code repeat getting codes from the Electronic Controller. Two, the memory can be cleared only by reading all codes present, all faults being corrected (anti-lock warning light off) and the vehicle being driven above 25 MPH."

[Guest flajunkie]

1 minute ago, Digger914 said:

Dirty/sticky switch possible, relay contact most likely. Pressure to turn off the pump is higher than pressure to run ABS, as your pump turns off I lean towards the ABS relay first, dirty sensor rings or connect to sensor cables second, dirty contact at pressure switch more likely on lower mileage car than bad switch, but pull plug connect and look for moisture from brake fluid just in case, otherwise plug and re-plug connector to switch several times to get fresh clean connect. Same for relays.

 

Was writing this when you posted codes, reseat plug connects to valve pack on brake assy and ABS controller several times and try again.

 

So pull all of the connectors off the brake assembly and inspect?

 

I noticed a while back that the locks for the connectors were off. Someone has been messing around with them in the past. Probably the %$#@ that sold us the car or the last Buick mechanic we had look at it a year ago.!

[Guest flajunkie]

4 minutes ago, flajunkie said:

26 Rear Inlet Valve (Disconnect 7 pin connector on Valve Block, measure resistance Pin 7-3, 5-8 ohms service harness, other reading replace valve block).

"...Two, the memory can be cleared only by reading all codes present, all faults being corrected (anti-lock warning light off) and the vehicle being driven above 25 MPH."

 

So this means the codes DID clear because the ABS light did go off today.

 

Since the code 26 came out of the ABS today with the ABS light off during engine running, the Rear Inlet Valve must be an issue. Could this valve leak internally to cause the pressure to drop off? Where is this valve?

[Digger914]

The valve is internal  and it could leak, or a bad connection to the valve pack or controller could be telling the controller that the valve is bad. Get the plug reseated good and tight and use some cable ties to hold it tight. Might want to check around your controller for signs of wet, sometimes convertibles leak at the strangest places.