Jump to content

Brake Accumulators... are they all the same? 1991 vs 1989?


Recommended Posts

Is the pressure gauge a standard tool? Where do I get one? Once hooked up, what am I looking for,  pressure, procedure. Thanks as always for your help Hemi!

The gauge set is a Miller Special Tool Gauge Set 6163 that was used at the dealer for testing the ABS accumulator and system pressures.

Basically, with the gauge hooked into the system, you would want to observe the gauge AS THE IGNITION KEY IS TURNED ON TO RUN.

If the pressure IMMEDIATELY jumps up to somewhere around 600# to 800#, and then climbs quickly to 2200# then the accumulator is good.

If, on the other hand, the pressure just begins to slowly climb from 0# and steadily continues to 2200#, that tells you the accumulator is defective.

The 2200# range is where the pump is turned off automatics.

With a good accumulator, each time you press the brake pedal, the pressure will drop a little until after 4-5 pumps the motor once again turns on and brings the pressure up to 2200#.

With a DEFECTIVE accumulator, the pressure will drop drastically the first time you press the brake pedal and will likely go to 0# on the subsequent pump.

post-83939-0-26807200-1441646314_thumb.j

  • Like 2
Link to post
Share on other sites

Just a little alteration to the explanation above. The pressure actually drives up to 2500# and then drops down to around 2200#

The brake pedal pump test can best determine a totally 'dead' accumulator as the pedal becomes 'HARD' on the first or second pump.

If you still have a reasonable pedal after 4-5 pumps, the accumulator is at least still somewhere close to good.

  • Like 2
Link to post
Share on other sites

Thanks, awesome advice as always Hemi. I suspect that the key is the fitting that goes between the accumulator ant the system. I see some for sale on line and would like to get one. Layman question....what is the thread size for the male and female ends of that fitting? 

Edited by vonblood (see edit history)
Link to post
Share on other sites

The subject of accumulators for the TEVES Mark II ABS system has been addressed quite a bit on the Buick Reatta AACA Forum.. 

 

Starting back in January, there was a lot of disappointment when the AC Delco accumulator became unavailable.  Shortly thereafter, one of the regular Reatta Forum.contributors, Ronnie, did some searching and discovered the HYDAC accumulator sold by Spinningwheels-sc in Florida.  This company has been selling this accumulator since 2010 and imports them directly from the manufacturer in Germany.  It is compatible with the TEVES Mark II system on the Reatta and has been widely accepted by the community.  The HYDAC unit is slightly less that 1/4" greater in height than the OE and, on the Reatta,  it is necessary to shim up one side of a cross member to avoid contact with the top of the accumulator.   

 

The OE accumulator had a specifiation of 15 cubic inches imprinted on it and the Hydac unit has a specification of 20 cubic inches on it.

The greater capacity will cause a larger, around 3/8", drop in the fluid level in the reservoir when in use but this does not impact performance.

 

I am not familiar with the configuration of the TC's TEVES ABS unit but chances are very good that the HYDAD accumultor will work well within the physical configuration.of it.

 

In use in the Reatta the HYDAC accumulator performs quite well and is in use by many owners. 

 

Initially, the Spinningwheels-sc sold the HYDAC unit for $135 plus shipping but the price on their latest order is now $155.00 plus shipping.  There are some re-seller(s) of the HYDAC accumulator who price the unit significantly higher.

 

www.spinningwheels-sc.com    Contact is Diane or Victor  Phone (352) 732-5013  Fax (352) 732-6537  Orders can be place through their website.

 

They are very straight forward folks and give excellent service.

 

The discussion of the  non-availability of the OE ABS accumulator for the TEVES Mark II ABS unit on the AACA Buick Reatta Forum started in January of this year and the most recent was made in July of this year.  The post has had 172 replies and 8,478 views.  Technical aspects of the Hydac unit are discussed extensively.  Might be worth a look.

 

Should the question be on anyone's mind, I have no financial  interest in the sale of the HYDAC accumulator. 

 

Kingsley Baker

Reatta Specialty Parts

Edited by Kingsley (see edit history)
Link to post
Share on other sites

I just bought one of the Hydac accumulators for my one TC that I've been working on. This car already has a Hydac on it, but I can't get more than 3 pumps or so out of the pedal before the pump comes back on. The ABS works fine, but I don't want to take the chance. I am also replacing ALL of the soft lines while I'm at it. We shall see if this makes a difference!

 

I have already replaced the pads and put an entire quart of fluid through the system flushing it.

Link to post
Share on other sites

I just bought one of the Hydac accumulators for my one TC that I've been working on. This car already has a Hydac on it, but I can't get more than 3 pumps or so out of the pedal before the pump comes back on. The ABS works fine, but I don't want to take the chance. I am also replacing ALL of the soft lines while I'm at it. We shall see if this makes a difference!

 

I have already replaced the pads and put an entire quart of fluid through the system flushing it.

DON'T WORRY about how many pumps it takes to make the pump come on.

3 pumps is enough to lower the pressure to a point that will reactivate the pump.

Link to post
Share on other sites

Ah..ok. I have read a few places that we should be seeing 5-10 "pumps" "stabs" "taps"....whatever of the pedal before the pump reactivates. The Reatta guys use the drop in fluid level as the accumulator fills, but that doesn't seem to work for us.

 

So, I need to get a guage then and test it? I *REALLY* don't want to pull that accumulator if I don't have to.

Link to post
Share on other sites

Ah..ok. I have read a few places that we should be seeing 5-10 "pumps" "stabs" "taps"....whatever of the pedal before the pump reactivates. The Reatta guys use the drop in fluid level as the accumulator fills, but that doesn't seem to work for us.

 

So, I need to get a guage then and test it? I *REALLY* don't want to pull that accumulator if I don't have to.

Do you actually think you have a problem? You said " The ABS works fine, but I don't want to take the chance. I am also replacing ALL of the soft lines while I'm at it."

 So, leave well enough alone. It sounds like you are in good shape.

Link to post
Share on other sites

Hemi, I honestly don't know if there's an issue. The brakes seem to work great, honestly. The ABS works (I've tried it a few times on purpose). I just don't want the system to crap out because the motor had to keep running or something.

Link to post
Share on other sites

 

Perhaps Febi 01817 is not a direct fit, but nonetheless is a fit. Today I got the accumulator with a remade nipple and it works fine. At least no worse than the old one. 
Braking is good, pedal is precise, ABS works good. 
 
It seems everything is good apart from the fact that the pump engages every two hard/deep pushes of pedal.
 
The reason I decided to replace my old accumulator was that the pump began engaging every two pushes. Frankly, I don't remember how it worked previously. Reading numerous forums I found out that it should switch on every 5-7 pushes. So I've replaced the accumulator.
 
I don't have any problems with braking force - the car brakes as it should. 
The pump works according to the following algorithm:   a) every 2 hard/deep pushes(fast braking to a halt, speed above 70 mph)
                                                                                     b)every 3 medium pushes(fast braking to a halt, speed 40 - 50 mph)
                                                                                        c) every 5 very soft/short pushes(fast braking to a halt, up to 30 mph)
Is it ok? Any ideas? Pressure switch?
 
As a whole Febi 01817 brake accumulator fits Jaguar XJ40 1994 MY after some work. It cost me $80 and I paid $20 to a local machine shop. Given shortage of these parts and high prices I think that option is a good one.
If anyone is thinking about replacement and has contacts of a good machine shop/turnery I would recommend Febi as the cheapest option on the market. Just dismantle your old one and ask a turner to make a complete copy of the neeple, including the lateral bore and cone notch.
 
Digger914 thanks for your post, it helped me to decide which part to buy. 

 

 

Update:

 

I'm writing here because I think this information will be usefull for TC owners: Febi 01817 accumulator does not Fit Jaguar XJ40 1994MY and possibly other cars with Teves II because it is not designed to work under high pressure that the system creates(or with brake fluid). After several weeks of operation Febi's diaphragm cracked letting nitrogen out to the brake fluid reservoir. During pumping brake pedal the reservoir was filling with foam; when I removed Febi accumulator and put it aside to install the old one the Febi's diaphragm literally exploded spewing nitrogen and remaining brake fluid to the air. I think that pressure of nitrogen in Febi is significantly lower so that diaphragm stretches too much under pressure of brake fluid. When I installed my old accumulator everything became normal again - no foam and bubbles in the reservoir. The number of presses has not changed - 3 presses before the pump engages again. This is another sign that Febi's pressure is too low.
Also, I replaced the original pressure switch with AC Delco 25530882($90 at Amazon) and it works fine apart from the fact that the low pressure light turns on when the accumulator is full and extinguishes when pressure decreases and the pump engages. It's very wierd, perhaps the original part and AC Delco's one have different algorithms of turning on the light. I've installed the original part back.
So, next I will try to buy a Delco 25528382 accumulator.
 
Hope this helps

Alex Kochkin

Russia

Link to post
Share on other sites

Update:

 

I'm writing here because I think this information will be useful for TC owners: Febi 01817 accumulator does not Fit Jaguar XJ40 1994MY and possibly other cars with Teves II because it is not designed to work under high pressure that the system creates(or with brake fluid).
 
Also, I replaced the original pressure switch with AC Delco 25530882($90 at Amazon) and it works fine apart from the fact that the low pressure light turns on when the accumulator is full and extinguishes when pressure decreases and the pump engages. It's very wierd, perhaps the original part and AC Delco's one have different algorithms of turning on the light. I've installed the original part back.
So, next I will try to buy a Delco 25528382 accumulator.
 
Hope this helps

Alex Kochkin

Russia

Bummer on the Febi part, that part number came from a cross reference chart for a Lemforder part that isn't available in the US. The Lemforder part number was a cross reference to the Jaguar part number that we both use. When the nipple mount didn't come as 14 x 1.5 the direct fit question became is the Febi number an incorrect match for the Lemforder part number, or is the Lemforder number an incorrect direct fit match for the Jaguar number, but the operating pressures should have been stamped on the ball and pressure is pressure whether the nipple end is a direct fit or not.

 

The ATE Teves pressure switch has an easy answer, these things come one of two ways. One is flat blade the other is round pin. One switch comes with 2 normally open contacts 1 normally closed, the other way is 2 normally closed 1 normally open set of contacts.  Even though your system is wired for a different controller than ours, in 1994 Ford owned Jaguar and thinking that Ford didn't reinvent the wheel, you should be able to use the same part number that the Lincoln and T-Bird people are using on their Teves II systems. That is if Ford didn't reinvent the wheel for Jaguar.

Link to post
Share on other sites

I don't think you had a problem to begin with. As explained to me by Hemi Anderson, it seems that your brakes were working perfectly fine before given the description you've provided.

Perhaps you are right, but people from Jag forum say that the norm is 5-7 good presses of brake pedal. I have(with both original and Febi part) only 2-3; my original accumulator is 21 years old, and I don't remember exactly how much presses it had when my father bought the car in 1997. Two years ago ebay was full of AC Delco accumulators for the price of $80-100 and I decided to postpone that issue. Now it is hard to find them for $250. Russian ruble has plunged 100% against dollar, so now it costs an equivalent of $500. That is why I'm so worried about replacement and don't want to postpone it again. No doubts that my accumulator will die in a couple of years(under the favorable scenario), so I would feel myself much more comfortable if I have one in my personal stock.

Link to post
Share on other sites

.... , but the operating pressures should have been stamped on the ball and pressure is pressure whether the nipple end is a direct fit or not.

 

The ATE Teves pressure switch has an easy answer, these things come one of two ways. One is flat blade the other is round pin. One switch comes with 2 normally open contacts 1 normally closed, the other way is 2 normally closed 1 normally open set of contacts.  Even though your system is wired for a different controller than ours, in 1994 Ford owned Jaguar and thinking that Ford didn't reinvent the wheel, you should be able to use the same part number that the Lincoln and T-Bird people are using on their Teves II systems. That is if Ford didn't reinvent the wheel for Jaguar.

Hi Digger914!

Unfortunately Febi has no pressure markings on its body. Actually, I was very surprised to find none. I have researched a little bit and found out that accumulators like Teves uses are manufactured in several types with operating pressures 100,160,210,250, and etc BARs. Also use of such hydraulic accumulators is not limited by auto industry only. They are used broadly in heavy machinery. And I guess that those accumulators that we can buy today, by HYDAC for example, are produced for such machinery like excavators. 

 

Here is one Chinesee manufacturer: http://accumulator.en.made-in-china.com/product/eoFJavtOEdrU/China-Hydraulic-Accumulator-Diaphragm-type-bladder-type-.html 

 

Copy/paste the link if it does not work directly.

 

Note, some models have 14x1,5 nipple!

 

So, I think that the Febi part had 100 or 160 BAR of pressure and that is why it ruptured under 210BAR produced by the system.
 
As for the switch, I bought Delco 25530882(green color, ATE logo on the connector) which has black rectangular connector with five flat pins - 2 in one row and 3 in the other - exactly like my original one(yellow, blue connector). I guess the Delco is an exact switch that Lincoln and Ford use, but if I'm correct TCs, Fords, and Lincolns have the accumulator, pump, and switch coupled with master cylinder like late Jaguar XJ-S had. My 1994 XJ40 is equipped with a separate electric pump unit, so it is quite possible that ATE - but not Ford - slightly modified their "wheel". The only difference between the original and Delco part is that the Delco is designed to be tighten/loosen with a 36mm wrench, but the original - 41mm.
Anyway, the fact is that the switch is working no worse than the original one, but the light is turning on contrariwise. I need to think a little bit how to rewire the light, in case the original will die.
Edited by kocha2009 (see edit history)
Link to post
Share on other sites

Perhaps you are right, but people from Jag forum say that the norm is 5-7 good presses of brake pedal. I have(with both original and Febi part) only 2-3; my original accumulator is 21 years old, and I don't remember exactly how much presses it had when my father bought the car in 1997. Two years ago ebay was full of AC Delco accumulators for the price of $80-100 and I decided to postpone that issue. Now it is hard to find them for $250. Russian ruble has plunged 100% against dollar, so now it costs an equivalent of $500. That is why I'm so worried about replacement and don't want to postpone it again. No doubts that my accumulator will die in a couple of years(under the favorable scenario), so I would feel myself much more comfortable if I have one in my personal stock.

For your own reference the 8V car I have been working on has a newer Hydac accumulator on it. I get 3 pumps on the pedal with medium/light pressure on the pedal. The system works perfectly (I've tested it on the street), and after speaking to Mr. Anderson (a very nice and knowledgeable/experienced person) I am just going to keep my replacement Hydac in storage until it's possibly needed (most likely I'll swap to regular brakes before I do that though).

Link to post
Share on other sites
  • 1 year later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...