delco brakes get them working successfully and well

[OwenGT3]

It looks like I'm gonna have to visit the abs brake switch problem again as my current set up has failed. 

 

I have a replacement pressure switch system with two switches replacing the original and since fitting the pressure gauge and setting the switches up correctly it has performed well. The problem is fluid has leaked past the adjust screw on the high pressure switch, I've driven it around for a while like this, even tried to seal the leak, but it's got to a point now that the switch has failed and leaking too much, so I've fitted the original switch back on the car which at least keeps the car on the road.

 

The low pressure switch is fine and have no other problems with my set up. I don't know if I was just unlucky with the switch and it's developed a leak, or it's something to be considered using switches not really designed for brake systems and mineral brake fluid.

 

I am now looking for a new switch for the high pressure side, I've found this one:

 

http://www.appeng.co.uk/product/pressure-switch-ps71-spdt-general-purpose

 

I'm just unsure what will be the best diaphragm material to use, also if the 2500 pressure is low enough to work well or needs to be lower.

Edited July 23, 2014 by OwenGT3

[dodge1979]

Owen..why are you trying to source a different switch and guessing which might be good for it. As documented, ive spent a few years on this subject and have developed the newest version which ive been testing. And its available from the UK as opposed to from half way around the world..which I tried to advise people against doing previously. .

And if you read back a couple of pages youll see why this will be a far better option than anything else

[philip600]

Hi Owen, the low pressure switch I bought from PVL also started to leak soon after I fitted them.I got a replacement from them under warranty which they said had a material for the diaphragm. No problems since ( fingers crossed ) but If I do have any more issues Darren has obviously spent a lot of time & effort sourcing a better alternative so this is the route I'll be going down.

[dodge1979]

Obviously any item can go faulty or be manufactured wrongly but its not a common thing. Ive fitted a few of the original switches I had made through PVL and Ive had no issues with any of them. Unfortunately, if it comes from Oz then that makes things harder and even more expensive than it was to begin with from there. stay local. The new version is worth it..

[OwenGT3]

Obviously any item can go faulty or be manufactured wrongly but its not a common thing. Ive fitted a few of the original switches I had made through PVL and Ive had no issues with any of them. Unfortunately, if it comes from Oz then that makes things harder and even more expensive than it was to begin with from there. stay local. The new version is worth it..

 

I did read this thread again, but couldn't find the switches quoted on the PVL site. The company I contacted in the link has said their switch is £34.29 for the nitrile diaphragm and £2.34 for the electrical connector, and it's in stock. My only issue with this switch was the pressure rating, unsure if starting at 2500 psi would be suitable??? I had the two switch system running at just over 2500 psi to keep the light off, any lower and it would go on all the time. The Lotus manual states it should be between 2050 to 2300 psi to operate the bump.

 

I drove my car today with the old switch and the light stayed off, I went through the city so I did a load of braking to see what would happen.

[OwenGT3]

They do the switch with EPDM rubber, so will get a price, but I didn't think it was too bad a cost.

[dodge1979]

Dont take this the wrong way, but it sounds like the system you got from Australia is shite. Thats the wrong pressures and not how it should function at all. Add on top how much extra it cost compared to the system id developed with PVL and the fact its not even returnable now its faulty so soon..it was money wasted. It seems to me theyve picked any switch that functions not developed it properly and flog it over priced.

The system originally available from PVL worked correctly and at the right pressures etc and was cheaper. Unfortunately, as mentioned before due to the greed of Matty's and the fact someone else went and gave them the details passing it off as their own work, is a shame..and now PVL won't supply the switch with small orders

Which is why the new one switch system is being kept close to myself until I have a full cost for you guys who want it.

[OwenGT3]

They did set the switches, but it didn't work on my car at the settings they had pre-done, that's why I had to get a gauge and set them myself. To get the light to go out and stay out it needed to settle between 2600- 2900 psi according to the manual, mine was around 2600 psi otherwise the light would stay on all the time once I had driven and used the brakes, if it didn't come on just standing.

 

I think I quoted the wrong pressures in my other post. To be fair Steve sent me a complete new set of switches when the first ones didn't work at no charge, and he was very helpful when I was sorting the problem. The new switches did work and have been working for some time, it's just one has leaked by the adjustment screw and why I need to replace it, the other has been fine once it was set using the pressure gauge. 

 

As they are after market switches, the best way to set them up is with a gauge which I have plumbed in all the time to keep an eye on the system.

Edited July 25, 2014 by ramjet

[dodge1979]

But your light shouldnt come on above 1850psi. .so they still wernt working right..all delco systems on the esprit are the same. So...

And they should come correctly set anyhow..without the need for end user adjustment except for when the diaphragms wear but that shouldn't be for a few years yet...fitting a pressure gauge is a good regular check tool..but I would be carefull to ensure that all the internal materials in the gauge are suitable for the agressive brake fluid..otherwise they may last a year or two then.....pop..leaky leaky . just an observation.

The new switch requires no user adjustment and no playing about.

[OwenGT3]

I've had no problems with my lower pressure switch. I adjusted it to go out at 1800 psi which it did, I think originally it was set too high before it put the light out, but once done it's been alright. Most of my problems have been with my high pressure switch not being able to settle with the first switch, this put the light on constantly. Then I got another switch and that worked, again after setting it up using the gauge.

http://youtu.be/ElG7sW-mg7s?list=UUTYWGuu2gDYJnLxNs71kt3Q

 

Occasionally my light would come on on a long journey or some hard braking, but 98% of the time it was off. The switch leaking was the only real issue.

 

What's funny now is, I've fitted my old switch back on and the light has stayed off for the two days I've used the car to work, no problems. I wondered if it was my old accumulator, it was low at 500 psi and went to 1200 psi when the new one was fitted.

 

That other company has come back to me, using the other rubber, still under £40 and in stock, so might try them if the old switch plays up again.

 

Noted about gauge, I can always blank the hole once it's set.

Edited July 25, 2014 by OwenGT3

[top-plumber]

How's your replacement switch coming along Darren?

[dodge1979]

Its performed perfectly so far. In honesty ive just had a lot of 0ther things happening that its took a back burner..

.but it has enabled me to do other tests and ensure its consistent. Just gotta sort out pricing with the company..

[Gasman GT3]

Put me down for one Darren when you are happy with it.  Dont need it at the moment but I'm sure I will at some point so will be nice to have one in stock for when I need it.

[OwenGT3]

I'm going to get one of these switches to replace my high pressure switch which is faulty. I can get it through work luckily as we have an account with RS, but it looks like it should do the job. Good pressure range, going for the 1000-3000 psi option, optional rubber parts so can have EPDM as well, and not too bad a price at just over £70 quid. I'll let you know how I get on, although at the moment the original faulty switch is holding up, albeit with the light on!

 

http://uk.rs-online.com/web/p/pressure-switches/7794288/

 

http://docs-europe.electrocomponents.com/webdocs/11fd/0900766b811fdad2.pdf

[OwenGT3]

Switch ordered, should arrive Friday, £78 including P&P. This is the high pressure side of a two switch set up.

 

It came from this company in the end, a GEM product. Ordered over phone and paid by card, very straight forward. Hopefully will plumb in Saturday, just got to get blank for set up once gauge is removed.

 

http://www.appeng.co.uk/

 

PS71-50-2MGS-C-FLS18-E

 

PS71 = Switch type

50 = Range, 1000 to 3000 psi

2MGS = 1/8" BSPM (G Type) Stainless Steel

C = SPDT Circuit

FLSI = Flying Leads with Heat Shrink Tubing 18" long

E = EPDM Diaphragm

Edited September 10, 2014 by OwenGT3

[markw996]

I'm interested in these switches, would be nice to get my brakes working after over a year of poor braking.

 

Does that pressure switch have upper and lower adjustments, or just a single hysteresis adjustment for the "deadband"?

 

**********************

 

EDIT: If I understand correctly, maybe it doesn't need adjustable hysteresis. If set to around 2800psi the average deadband will be 220 to 500psi (according to the specs) which is roughly near the 2400psi range required.

Edited September 11, 2014 by markw996

[OwenGT3]

Here's all the info on the switch and how to spec it. It says deadband is 70psig.

 

http://docs-europe.electrocomponents.com/webdocs/11fd/0900766b811fdad2.pdf

 

My other switches for the two switch set up I had were 2300-6000 psi and 2700 psi. The first one just never settled, it was always switching on and off, so the second one was fitted. I've had no problems with this switch other than the adjuster leaking, this is why I'm fitting another one. Low pressure switch has been no problem.

 

The only other range to go for in the new switch is 2500-5000 psi. I decided to go for the 1000-3000 psi as the system isn't meant to go above 2700 psi, the safety valve is 3400 psi, so hopefully my range will be suitable, the only way to find out is to try it!

Edited September 11, 2014 by OwenGT3

[stephenbirdsall]

Wow, what an awesome thread. It's the only technical one I've read through in all my years on here.

 

As you can see, I've been a member here for years and always wanted to get myself an Esprit but, apart from the fact that I had insufficient money, I was always a little worried about the ABS on my preferred model, the S4s. With all the hard work you've put in, I'll be confident when I start looking at cars again.

 

I just wish I'd been able to buy one a few years ago.

 

On a different note, does PM have a history of using (and profiting from) other people's ideas like they have the one from the start of this thread? It's one of the few names I recognise as having a lot of Esprit knowledge.

 

Actually, don't answer that last question, I'll just keep an eye on the situation myself.

 

Thanks again to Darren for all the hard work you've put in.

[dodge1979]

So the switch your going for then isnt correct for the system. The system CAN go above 3000psi quite safely. The pressure release is set at 3400psi for a reason. If anyone fitted that switch then the pressure safety aspect of the system wont work and the switch will fail before the pressure relief cuts in. Messy result.

Its not a question of trying any switch and seeing how it goes..ive spent nearly 3 yrs on this now to get to the stage im at with the new single unit switch and really dont recomend cobbling something together..the one being mentioned above is cheap for a reason.

[sanj]

Not to speak to its suitability in any other way, but the switch he referenced is proofed to 6000psi regardless of sensing range, with a burst limit of 9000psi. The range merely determines the available switching point.

[OwenGT3]

So the switch your going for then isnt correct for the system. The system CAN go above 3000psi quite safely. The pressure release is set at 3400psi for a reason. If anyone fitted that switch then the pressure safety aspect of the system wont work and the switch will fail before the pressure relief cuts in. Messy result.

Its not a question of trying any switch and seeing how it goes..ive spent nearly 3 yrs on this now to get to the stage im at with the new single unit switch and really dont recomend cobbling something together..the one being mentioned above is cheap for a reason.

 

At this point in time I have a car I want to keep on the road, so the brake switch needs to work. The original switch is knackered however many times I clean it. I'm no expert on pressure switches, but from what I've read and asked people who know about electronic switches, I found a switch that is not too bad a price and offers switching within my operational range, and as Sanj said has a proof pressure over what is required of my system pressure.

 

As I've already had a two switch set up on my car, my system with this set up never once went over 3000 psi, so I believe the operation range of my switch should be suitable. Until a suitable alternative comes along, whether this is the switch you are developing or someone else's, I have no alternative but to buy a switch that I think will do the job.

 

My two switch set up which was the Lotus Marques set up did work fine on my car once I had set the pressure switching correctly with a gauge. I'm only replacing the high pressure switch because of the leaking adjuster screw, unsure why as the low pressure has had no problems. The new switch is no different to the others I have already.

Edited September 12, 2014 by OwenGT3

[dodge1979]

The way it reads is that the chosen item has a range of 1000to3000psi..not 6000. Hence me saying it is not suitable to perform and maintain its ability to enable the over pressure safety aspect of the system to perform.

[sanj]

Incorrect. All of the switches listed in the PDF have the same rating with respect to proof and burst pressure, 6000 and 9000 psi respectively. Look at the first page:

 

Specifications
Switch SPST; SPDT
Repeatability See Table 1
Wetted Parts
Diaphragm Nitrile (optional EPDM, Viton® or Neoprene)
Fitting Zinc-Plated Steel (Optional 316 SS)
Electrical Termination DIN 43650A IP65; Spade Terminals IP00; Flying Leads IP65;
Conduit with Flying Leads IP65; IP option IP66
Proof Pressure 6000 psi (414 bar)
Burst Pressure 9000 psi (600 bar)
Approvals CE, UL Approved units available
Weight, Approximate 0.4 lbs. (0.15 kg)
 

Edited September 13, 2014 by sanj

[dodge1979]

Ok. ill say it again. What was written in the txt above reads 1000 to 3000 psi as the chosen one. I didnt see a pdf link.

[sanj]

He posted the link in post 192:

Here's all the info on the switch and how to spec it. It says deadband is 70psig.

 

http://docs-europe.electrocomponents.com/webdocs/11fd/0900766b811fdad2.pdf