PontiacDude210

Brake Accumulator Alternatives

Recommended Posts

I'm in need of brake accumulators and without $800 free floating cash for 2 n.o.s. units that are still 20+ years old. I've tried to start this discussion before because I think a lot of Reattas and Rivs would still be alive if people thought the brakes system was repairable.

My first thought would be to find an accumulator from a BMW, Audi or Mitsu that is still being manufactured, holds the same pressure or slightly higher, and has a close enough thread size to inconspicuously adapt it to fit it up. I cannot find any database on what pressure and thread sizes other manufacturers accumulators run. I requested a list of Teves info from ATE/Continental as a cross ref, but I was told they could not help me. I thought also to look for an equivalent from industrial supply catalogs, but most hydraulic accumulators are not listed by thread spec or pressure capability, but by what it replaces.

I also though about the recharge info a lot of audi owners are using, inasmuch as I have all winter to play with the brakes in my driveway and at the abandoned church a half mile up the road. I could put a recharged unit on the one I'm not insuring and play with it until becomes obvious whether or not it will hold up. I know that's super risky and all that happy crap, but I know what it feels like to drive a Teves car that has a shot accumulator, it isn't keeping me up at night.

The last option is converting to a conventional booster. Not something I'm really interested in, but if anyone has come across a quick, easier than repairing the Teves unit way to do this, then shoot.

Just to clarify, my driver Reatta has a functioning accumulator that is starting to wear down. It passes the test slightly under par. My new project Reatta has a bad accumulator. I don't want this to become another debate on whether or not to keep driving a car with a bad accumulator. We all know the accumulator is safety essential, and we all know a different accumulator voids your 400 point potential. Some of us need real options for safety concerns however, regardless of originality.

Share this post


Link to post
Share on other sites

Attached is a parts book page from AUDI...... note that this accumulator is remotely located (it also is different as it has two ports...for some reason) With a custom made brake hose, we could remotely mount a standard industrial accumulator. One end would attach where the present accumulator is located, I am thinking with a "banjo" type fitting and the other end would screw into the chosen accumulator.

A good hydraulic store could help us select an accumulator of the approximate size, capacity, and preload as the factory unit. I suspect the price would be similar and most industrial units are rechargeable.post-30596-143142921884_thumb.jpg

Share this post


Link to post
Share on other sites

I think a remote mounted audi unit may work. The Mitsu and some BMW units look very similar and are similar size, can be had new for about half what a GM NOS unit goes for, wondering if those may hold any promise?

Share this post


Link to post
Share on other sites
Guest my3buicks

I am surprised GM has abandoned the accumulator, between Reatta's, Riv's and the other GM marques that used them there are a lot of cars out there. I guess GM doesn't need the money they could be making parts for these vechicles.

Share this post


Link to post
Share on other sites

210, I share your concerns about the lack of available accumulators. We were spoiled for a few years by the accumulators being so cheap and readily available. People still expect to get them for those prices but I think the days of $100 accumulators are gone. Before someone will reproduce more accumulators they will have to be assured people will pay a price high enough to make it a worthwhile investment. The question is, what would people be willing to pay for a suitable replacement? You mention $800 for 2 accumulators in your first post. What would be a fair price for a new accumulator that would work on our cars now that the old stock is gone?

Share this post


Link to post
Share on other sites

We just got the first batch of our reproduction accumulators from Germany. All have been sold already. The next shipment should be here soon.

These are not NOS. Date code is 11/14. They are brand new. Our accumulators are $350 each.

I installed one on my own car just to test fit.m to make sure they matched the specs we sent the manufacturer. They are a little larger and may require a couple washers on the strut brace studs on some Reattas, but work flawlessly. 3-4 pumps before the pump cycles again.

Share this post


Link to post
Share on other sites

Still, $700 for the 2 accumulators... ouch. I guess if we are talking a one time investment per car, it lightens the shock a little. It certainly doesn't make me want to go get another Reatta, the near guarantee that it will need a $350 accumulator, $200 plus 25 hours of work into new motor cradle bushings, $160 in headlight work, $200 for fixing the pops in the original stereo, etc. are all almost inevitable fixes on a decent "driven" condition Reatta. I'm trying to find ways to safely, reliably and repeatably ease the financial burden of owning a unique car. And it's because I'm tired of seeing nice cars sell for $800-1000 only to be parted out, left to rot, given up on, or horribly cobbled together in a sub par manner. And that starts with questioning like "How can I repair the brake system safely without jumping through hoops, calling dealerships, knowing who to private message on what forum, reading threads on it for hours without conclusion, or selling my firstborn to a Greek demigod in exchange for one?" If we had a cross reference that said

Common problem : recommended fix : compatible parts : additional needed components : link to tutorial that probably already exists on the forum somewhere

I can't believe that none of the similar size BMW accumulators run the same pressure. I can't believe none of these can be adapted to fit. Nobody has tried it yet, but that doesn't make it unsafe or impossible. The BMW units can be had in large numbers for roughly half what the AC Delco can.

Side note: we should seriously pin a thread which has a compilation of common safety problems and concerns. I keep finding out things like "everyone knew about the bushings except you." An FAQ on safety and handling with general info links would be enormously helpful.

Share this post


Link to post
Share on other sites

Someone posted here (or maybe on the ROJ) about installing one of the Mitsu. accumulators on their Reatta and closed by saying it works. He wasn't a regular poster. It was within the past three-four months that it was posted. He even provided a link to Amazon for it. I remember thinking that people would jump all over that but it barley raised an eyebrow. Huh.

Common problem : recommended fix : compatible parts : additional needed components : link to tutorial that probably already exists on the forum somewhere...

Side note: we should seriously pin a thread which has a compilation of common safety problems and concerns. I keep finding out things like "everyone knew about the bushings except you." An FAQ on safety and handling with general info links would be enormously helpful.

The closest anyone has come is Ronnie and his (under-appreciated) web site.

John F.

Edited by Machiner 55 (see edit history)

Share this post


Link to post
Share on other sites

If you have been in the old car hobby for as long as some of us, you see a common trend. At some point, the price of maintaining a particular vehicle separates the men from the boys.

Let me explain. All of us can remember older cars that were available for reasonable prices and replacement parts were not a problem. One car that comes to mind is the Corvair. At one time people would almost give you a Corvair to get rid of it. However there was a strong following and Corvair owners usually had several cars both to drive and for spare parts. Not everyone can have a parts car at their house, so parts must come from somewhere.

When parts start to get harder to get, vendors start to get interested (if there is really a demand) and they often reproduce a hard to get part. In the case of accumulators, that is necessary to keep the car on the road, while something like a logo, radio, air or oil filter can be ignored or substituted.

This is where the separation begins. The owners that have a Corvair or Reatta that need a part is at a crossroad.......do you search for a part and pay a high price OR move on to another vehicle/brand that is more available. We are at the 25 year mark on the Reatta and there is some good news in that many of the parts were used all four years, plus our cousin the Riviera is also a donor. However there are some items

that we will need to make the decision on whether to reproduce or substitute to keep the car looking good and on the road.

Each Reatta owner will make the decision based on their own circumstances. Liking or loving the car will play into the final decision but parts availability will be a big factor.

Marck has made a decision to have accumulators reproduced. This is difficult for vendors to do, they could make nice $$ or loose $$ all depending on how owners feel about their Reatta.

The convertible weatherstrip has been discussed here several times and that is a large investment for a vendor, the price of the parts will be high for the vendor to recoop their investment and hopefully make some money on the parts. There are only a few vendors interested in the Reatta because of the low voluum build. Hang on, this could be a bumpy ride.

Share this post


Link to post
Share on other sites

John, if you or anyone else finds that post again I would be interested to see it. I noticed the Mitsubishi unit looks very similar. I've dug through what feels like hundreds of brake related posts and I feel the information on them needs compiling. I feel the same way about the engine cradle issue as most questions have been answered but are spread across many threads.

Mr. Eaton, I have not been in the old car hobby as long as most, I bought a fairly odd duck Volkswagen when I was 15 and that was my start in to it, albeit only 7 years ago. I've found that pick a part yards and older dudes with yards full of parts cars are very helpful, both in the parts and know how dept. I however feel that there is another route to be explored, that of fabricating, cross referencing, and reusing, all according to cost, quality and safety. Because a n.o.s. Delco unit can be had for $400 on eBay doesn't mean that's the only route, especially if a unit for a BMW which costs less works just as well. Exploring those options is the purpose of this thread.

I have been in contact with a person who recharges accumulators. I've been asking him about the bladder in the accumulators, as he has taken several other brands apart, and the effects of age and use on the degradation of the bladder. He leak tests his accumulators before returning them to operation. I would be interested to have one charged and monitor its longevity vs. a new one. On that topic, does anyone know off the top of their head how much pressure the Teves accumulator needs?

John mentioned Ronnie's site. I'll say it again, if I have a problem, I'm reading the ROJ right there in my garage. It is my go to source for info, and Ronnie is meticulous about keeping the info accurate.

I would like to make a list though, of things newer Reatta owners should know, including the cradle bolts, the splices, what you can do if your accumulator fails(hoping to explore more options here), perhaps a cross ref of some suspension and wheel info, etc.

Share this post


Link to post
Share on other sites

While Ronnie was a bit blunt in his assessement in regards to finding parts to keep our cars on the road he is correct. These cars are wonderful to drive and pretty easy to maintain. Parts are a different issue. Once you get past the "easy" parts and are looking at Master Cylinder, interior trim and electronic parts that is where the problem starts. we are fortunate that a number of vendors have stepped up to help us with parts, but we must remember the time of low cost parts may be past.

So as I have always advocated keep your eyes out for parts and build your own inventory, buying what you can find cheap as possible. You will always be able to sell them. If you don't build your own inventory you will be at the mercy of the suppliers.

In regards to information, Ronnie has done an excellant job of listing a "How to" library. It is there for all to use. Personally I think he should charge for it, but he doesn't so that is a blessing.

Anyone can come out here and get pretty good answers to repair their particular issue. I have been on this forum for 8 years as well and have heard many of the same questions asked over and over. It doesn't get old because I appreciate the enthusiasm of the new Reatta owner and are glad they feel welcome enough to ask for help. Many other forums are not like that. We are a chatty bunch that likes to share.

Share this post


Link to post
Share on other sites

My post is deleted. Don't want to offend anyone. Too much bold text used in it made it seem blunt I guess.

Share this post


Link to post
Share on other sites

When I was fixing the brake mess on my car. I had the pump fail and replaced the master cylinder and pump with a used unit. While trying to get the original one working. I had it all laid out on a bench. I removed the Allen plug that was on the top back of the pump assy. I was trying to figure fluid flow paths. From what I found it seemed like you could put a fitting in place of the plug and apply fluid in to the system here and would come out to the accumulator and to lines. I was thinking a good diesel fuel fuel pump might be able to supply the fluid for a failed pump, not sure if one could supply proper pressure to the system without accumulator. Air Dog and other Diesel fuel pumps are more expensive than the accumulators and or replacement pumps right now. So this is why I did not test my theory.

Edited by Dashmaster (see edit history)

Share this post


Link to post
Share on other sites

Looked on amazon the [h=1]Mitsubishi Power Brake Accumulator 4630A011 is still available they have 2 left. Sorry the font changed after the cut and paste.[/h]

Share this post


Link to post
Share on other sites

Ronnie, no offense was intended toward you or the ROJ. The bold font wasn't what made your post blunt though. I was going to offer my list of "Things 'good deal' Reattas frequently need" to you for the journal upon completion, but I thought my writing style to be technically inferior to the work on the journal and didn't want to insult you by offering something I wrote.

I am ready and starting to get the wheels turning on trying other options on accumulator replacement. That's the point of this thread. I was hoping someone had done some more analysis as a jumping off point the way the chrysler tc people have, that's fine that nobody has. I am willing to put in the leg work.

I am guilty as charged. I found 2 nice cars and paid little for them. That doesn't mean I'm here to complain about maintenance costs without doing something about it. I'm not broke now, I was when I started on the first one.

Like I said, my thought with this is to find alternative ways to repair the accumulator problem. Eventually, to compile a list of problems you will inevitably face with this car and more options to fix a driver that does not need to be a 400 pt car. This isn't intended to compete with anyone else's database, journal, pinned boards, etc. It isn't going to compete with the ROJ. I'm not complaining about the work already done, I'm aspiring to do more work mainly on cross compatibility of certain key parts, but also compilation work of digging up every way certain issues have been solved and putting them in one place. Most of it WILL BE A REHASH OF THE ROJ WORK AND THIS FORUM AND THEREFORE REDUNDANT (can't cold font on mobile), but the format will be different.

I will be back to report in a few weeks. Going to start trying other methods. The Chrysler people had some interesting thoughts.

Share this post


Link to post
Share on other sites

Here are some numbers from a GM training manual..... title Teves Mark II Antilock Brake System, published by GM Service Technology Group and dated 1993.

Page 3-29 under Accumulators......they are precharged with nitrogen at 600-1300 psi.

Page 3-30 under Pump Motor.... when accumulator pressure drops below 2,000 psi, the pressure switch grounds causing the pump to run. At about 2,600 psi the pressure switch opens, turning off the pump.

Below is a picture showing the different stages of charge for accumulators. I added some dimension to the center view for reference. Diaphrams do fail but not that often, the failure is just a time factor.... like tires, sometimes they slowly leak, loosing a 1300 precharge over 20 years is not bad, most companies would not consider that a bad part, nothing last forever.

This picture also demonstrates how you can evaluate an accumulators condition by the amount of fluid pulled from the reservoir.

(1) In the first picture (left side) , note there is no fluid in the accumulator, it is pushed out by the precharge when the system is discharge.

(2) When pressurized, fluid comes in the connection at the bottom and starts to move the diaphram and compresses the precharge up to the 2600 psi pressure setting noted above.

(3) As you loose precharge, the pump is able to push more fluid into the accumulator as the precharge demises over time.

(4) Eventually the precharge gets below the point that the pressure switch can regulate the on and off of the pump motor and you have brake problems.

(5) By measuring the fluid drop in the reservoir, you can estimate the condition of accumulators. A really good accumulator will oniy allow the reservoir level to drop about 3/8 inch. As that measurement get larger... around 1/2 inch drop you need to order a new accumulator. All these rough measurements have come from trials using different accumulators.

(6) The far right picture of a depleted precharge, will give you a totally different reading if you try measuring the fluid level drop. Since there is little prepressure to push the diaphram down no fluid is pushed back into the reservoir, so in this case there is no change in the fluid level.... you will get the same condition if the diaphram has failed

post-30596-143142923121_thumb.jpg

Share this post


Link to post
Share on other sites

PD210 (and everyone else who is looking for an accumulator)

I don't fully understand your last post. It seems to be directed at me in a negative way but it doesn't matter. I think my last post was misunderstood but that is Ok too.

Maybe I'm blunt but I'm also known to be a problem solver. I have been tracking the price of accumulators for years. I posted alerts in the Buy/Sell forum when the prices dropped so people could take advantage of it. I was researching the accumulator problem before this thread was started. I was going to keep my findings quiet until I had one of the accumulators I found in hand so I could test it on my car to make sure it would work. Now that you have started this thread and you appear to be serious and willing to spend some money, I don't want to see you buy something that won't work. That is why I have decided to post this now.

Here is what I found. HYDAC ACCUMULATOR BALLS

It is a alternative to the factory accumulator that should work. And best of all it is affordable. It isn't a duplicate of the original but it is very similar. It has been tried and tested on Lincolns and Fords with the Teves Mark II Antilock Brake System like ours for a couple of years.

I have contacted the seller and he assures me that these accumulators will fit a Buick Reatta. He says they are currently out of stock but a shipment from Germany is already in the U.S. and is on it's way to him by truck. He is going to notify me when they arrive. Don't be surprised if someone throws a wrench in this deal and he jacks up the price when he finds out what others are asking for them.

Anyway, I hope this helps someone who is in need of an accumulator.

Edited by Ronnie (see edit history)

Share this post


Link to post
Share on other sites
Guest my3buicks

Is there a way to tell if used accumulators are good or not?

Share this post


Link to post
Share on other sites
Is there a way to tell if used accumulators are good or not?

Wondering the same thing actually. I think if there is a way to determine if the accumulator is structurally sound, there is possibility of even servicing them.

Thanks Mr. Eaton for the info. That will help me.

Thank you Ronnie for the info as well. I'm not sure why you're taking my tone so negatively, I Like your site and I appreciate your knowledge. My wish to compile data in a way different from yours isn't me trying to undermine you or be condescending. I don't feel the Delco accumulators are a long term solution. If what I've said bothers you, please PM me.

I am moving forward with an experiment with the help of a currently unnamed individual who has asked to remain low key. I will also purchase one of the ones Ronnie linked to afterwards to compare, if they are available after I get through some other issues going on right now that are completely unrelated.

Share this post


Link to post
Share on other sites

PD210-

I commend your efforts on this. I'd have liked to sort this one out myself, but lack the time and immediate need to do so presently. I would like to add that I think Marck's efforts should be supported to the greatest extent possible, as we will never encourage further vendor efforts at reproduction parts if they can't make profit from their early attempts. I realize we may never achieve a large selection of reproduction items for the Reatta, but we are guaranteed not to if there is no market to be found for those items when an effort is made.

That said though, I realize the price will be an issue from some owners, and there is also the question of just how far into the future he will be willing and able to provide repro accumulators. Will the manufacturer be willing to run off batches still in 5 or 10 years? We need something that can reasonably be expected to be available in a decade or two still. Maybe that is a pipe dream and we will have to continually reinvent the wheel everytime a substitute part is obsoleted.

A lot has changed in cars since 1988 and the next 25 years undoubtedly hold even more changes and challenges in terms of parts that can no longer be sourced. The suitable substitute we find today may be discontinued as well at any time. With accumulators at least, it seems they hold up well in long term storage as NOS parts so buying extras now should be sufficient to keep for use in say 10 years.

Just some thoughts.

KDirk

Share this post


Link to post
Share on other sites

For those of you veteran long time Reatta owners, here is a question. What is the average lifespan, in years or mileage, of a new accumulator? I realize there are a lot of factors involved, just trying to plan for the future as best as possible.

Share this post


Link to post
Share on other sites

Without making a tester (a working pump could be used as the base unit) the other option is to make an adaptor for the high side line that would include a pressure gage that would go to 3,000 psi.

On '88-'89 cars, you would remove the high pressure line that goes from the pump to the booster and install the test gage. With that in place you could check the on/off pressures of the pressure switch. That along with a reading of the fluid level drop in the reservoir would give you some good numbers to evaluate the accumulator and the rest of the system. I am attaching a sketch of a gage adaptor.post-30596-143142924186_thumb.jpg

To make it easier to install, one end would be a flexable line like you find at each wheel.

post-30596-143142924182_thumb.jpg

Share this post


Link to post
Share on other sites
PD210 (and everyone else who is looking for an accumulator)

I don't fully understand your last post. It seems to be directed at me in a negative way but it doesn't matter. I think my last post was misunderstood but that is Ok too.

Maybe I'm blunt but I'm also known to be a problem solver. I have been tracking the price of accumulators for years. I posted alerts in the Buy/Sell forum when the prices dropped so people could take advantage of it. I was researching the accumulator problem before this thread was started. I was going to keep my findings quiet until I had one of the accumulators I found in hand so I could test it on my car to make sure it would work. Now that you have started this thread and you appear to be serious and willing to spend some money, I don't want to see you buy something that won't work. That is why I have decided to post this now.

Here is what I found. HYDAC ACCUMULATOR BALLS

It is a alternative to the factory accumulator that should work. And best of all it is affordable. It isn't a duplicate of the original but it is very similar. It has been tried and tested on Lincolns and Fords with the Teves Mark II Antilock Brake System like ours for a couple of years.

I have contacted the seller and he assures me that these accumulators will fit a Buick Reatta. He says they are currently out of stock but a shipment from Germany is already in the U.S. and is on it's way to him by truck. He is going to notify me when they arrive. Don't be surprised if someone throws a wrench in this deal and he jacks up the price when he finds out what others are asking for them.

Anyway, I hope this helps someone who is in need of an accumulator.

I have done a bit of checking on the website mentioned by Ronnie above. They seem to be legit and appear to have a good product - so I bought one at an attractive price. Should have it within several days.

Kingsley Baker

Reatta Specialty Parts.com

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...