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I'm done with the brakes | Powermaster III nightmare | Partslist for conversion - Suspension/Brakes/Wheels/Hubs/Steering/Geo - The Lotus Forums #ForTheOwners Jump to content


I'm done with the brakes | Powermaster III nightmare | Partslist for conversion


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Dear forum,

I've gone through a long and frightful nightmare (not to mention costs) with my ABS. In the recent years I spent over 2000€ into

  • replacement switch (Ralf Burk, Germany)
  • solenoids (front, both)
  • pressure reservoir
  • endless, costly bleedings by Ramspott&Brandt

To no avail. The brakes are crap, either they work mediocre, or the tell tale lamp plays disco, and now: The car pulls to the right when stopping, to an extent that is more than just dangerous. I've decided to either sell the car to someone willing to bother with the brakes or convert it to something like the SE setup.

As I really enjoy the car when it stops(!), I'd like to ask and have a plea: Please help me with this conversion project. I got support from the workshop and a brave mechanic at hand. Is there anybody able to tell me how it's done? I already saw some threads from owners doing that successfully, but some sort of *partslist* or *how-to-guide* would be more than helpful - not only for me, I think. This could be "the" topic for anyone looking out for a permanent solution.

The number of existing topics with ABS problems speaks for itself, and replacement parts are not available any more (or at a ridiculous price). Workshops don't like the system either, as it produces headache and isn't straightforward to maintain. I don't want to start a discussion about "does it make sense" or "any ABS is better than none", because I personally made up my mind about this system.

I appreciate any and every help!

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Hey, 

I think I recall some people putting in an MR2 or MX5 master cylinder+vacuum booster in their SE's when eliminating the DMIII system. Should be some leads on the page. If you study the old vacuum routing pre-ABS maybe you could figure out a way to plumb into the system on your S4. Sorry I can't offer any more concrete advice.

Silly question but (regarding the car dangerously pulling to one side) - have you checked your brake hoses? My original factory rubber hoses split last year on my V8, one side at a time - this is exactly the behaviour I had. 

The DMIII system doesn't give the best feel, I'll admit that, but when it works it works. What's more, maintaining it is described in detail in the service notes, unlike the V8 whose Kelysey-Hayes ABS needs a special Tech1 cartridge which seems to be unobtanium. 

I'm guessing you've already switched the accumulator and ensured all fuses are working (when I accidentally pulled my brake light fuse, the ABS started blinking)...

 

 

Vanya Stanisavljevic '91 Esprit SE | '97 XK8

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The 89SE's master cylinder system works great with my upgraded 4 piston front and rear Brembo's.  The master is off of a VW Transporter.  Search the forum.  I would recommending going to the 89SE spec non-ABS system.

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Travis

Vulcan Grey 89SE

My Lotus Photo and Projects Album

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For what it is worth. I finished working on the abs system in my 93 last week. I replaced the accumulator with a wabco stc2784 but it had to be machined so that it would sit further into the bore. The system took alot of time bleeding (over 3 hours) and you have to follow the instructions in the service manual to a tee or the system will not bleed. How often does the pump come on when you press the brake pedal? To give you a example my pump only comes on after 9-10 times that the brake pedal is pressed. One item that i do wonder about is the stock of these accumulators. I would think that many are new old stock accumulators. My personal opinion is that even though they are new i would tend to think that the nitrogen would leak through the bladder in the accumulator because of the high pressure. As for your problem with the car pulling to one side i would tend to think that a caliper is sticking. The powermaster system is balanced front to rear not left to right. The system would not cause the problem you are saying. As for the abs light playing disco. I believe that is the switch that is causing the problem. from what i have read it is the way the switch is made that will cause a small flash in the light. I hope this helps (most likely will not) but the only other options are the toyota mx2 or a pre 90 master cylinder. Personally i would keep the power master and work it through.

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D.C. -

It is possible there could be something wrong with the suspension or tyres. If that is the case, then if you change the braking system to a vacuum servo, the problem could still remain, so I would try some other things first. Some suggestions:-

Have you swopped the flexible brake hoses from side to side?

Same for calipers?

Same for brake pads?

Is the suspension geometry within Lotus tolerances?

Do you have a weak spring or defective damper on one side?

Are your tyres matching?

If you do decide to do any swopping, do it one piece at a time, or you won't know which one is causing the fault.

 

Margate Exotics.

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Thanks for all your helpful hints and tips. There are some very informative bits that may indicate where to look at (which I will do and report):

Quote

How often does the pump come on when you press the brake pedal? To give you a example my pump only comes on after 9-10 times that the brake pedal is pressed.

After the pump/switch/reservoir-assembly got replaced 3 months ago (!), the pump runs every 2 times (on average) the pedal is pressed. There is some issue with the pressurizing then - I noticed that and already thought that there is a problem. Interestingly the switch doesn't send an error code nonetheless.

7 minutes ago, ian29gte said:

Do you have a weak spring or defective damper on one side?

This will be checked, as it hasn't been ruled out yet.

8 hours ago, tmusc said:

i would tend to think that a caliper is sticking. The powermaster system is balanced front to rear not left to right. The system would not cause the problem you are saying.

This is my next item to be checked - I will do so. VERY IMPORTANT info for me is, that the system runs front/back and not left right! That could mean I am lucky and the system itself is not the real culprit!

13 hours ago, Vanya said:

have you checked your brake hoses?

Will do!

Thank your very much for you strong support. I will try to thoroughly check all points mentioned and give you some feedback.

BUT: The main topic was "how to change the whole setup". So if anyone got experience with that here or could support me with info, I'm sure I'd not the only one that would benefit from that.

Cheers!

 

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12 hours ago, Vulcan Grey said:

The 89SE's master cylinder system works great with my upgraded 4 piston front and rear Brembo's.  The master is off of a VW Transporter.  Search the forum.  I would recommending going to the 89SE spec non-ABS system.

This. The feel of the '89 is ace. 

Vanya Stanisavljevic '91 Esprit SE | '97 XK8

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Having driven Owen's GT3 with ABS (Delco), and my daily driver having ABS, if I had a car that had such an awful experience under heavy (but not emergency-stop) braking, I too would be removing it.

I have the old servo-assisted master cylinder, Brembo etc rear brakes and customer fronts (4-pot Sumitomo from Nissan 200SX with 309mm x 32mm rotors), so a similar experience to Travis, a decent progressive brake feel, with not excessive foot pressure required. In fact another (TE, with AP brakes) drove the car once and was caught out by how much braking force can be achieved.

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16 hours ago, Vulcan Grey said:

The 89SE's master cylinder system works great with my upgraded 4 piston front and rear Brembo's.  The master is off of a VW Transporter.  Search the forum.  I would recommending going to the 89SE spec non-ABS system.

 

There is a tutorial online of an Esprit owner who disables the ABS on a later model to improve brake "feel", then wires in resistors to get rid of the light. 

 

I haven't done it yet, as I'm so bloody happy to have brakes again that I didn't dare tempt fate, bit will shortly.  I will report back if the difference is significant.

 

Second last thing I want on my Esprit is ABS, lol.

 

 

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2 hours ago, andydclements said:

Having driven Owen's GT3 with ABS (Delco), and my daily driver having ABS, if I had a car that had such an awful experience under heavy (but not emergency-stop) braking, I too would be removing it.

I have the old servo-assisted master cylinder, Brembo etc rear brakes and customer fronts (4-pot Sumitomo from Nissan 200SX with 309mm x 32mm rotors), so a similar experience to Travis, a decent progressive brake feel, with not excessive foot pressure required. In fact another (TE, with AP brakes) drove the car once and was caught out by how much braking force can be achieved.

I thought the GT3 had the Kelsey-Hayes system like the V8, not the Delco?

Margate Exotics.

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17 minutes ago, ian29gte said:

I thought the GT3 had the Kelsey-Hayes system like the V8, not the Delco?

98MY onwards for both the 4cyl and V8 cars. The new style of dash meant new style of brakes for both models.

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The feel of the 89 master with vacuum servo is great, has always been firm and linear.  It is also still great now that I upgraded to massive Brembo 4 piston front and rear calipers with floating rotors.  No need for a proportioning valve either.

I've driven the Delco ABS Esprits and the Kelsey Hayes Esprits, Elise and Exige... 

I've driven 

'89 Esprit - Vacuum assist non-ABS

'89 SE Esprit - Vacuum assist non-ABS

'90 SE - Vacuum assist non-ABS

'91 SE - GM PowerMaster III ABS

'91 X180-R with AP Racing brakes (same as Sport 300 4pot front and rear) - GM PowerMaster III ABS

'94 S4 - GM PowerMaster III ABS

'95 S4s - GM PowerMaster III ABS

1999 Sport 350 (with AP Racing 4 pot calipers front and Brembo 1 pot rear) - Kelsey Hayes ABS

2003 Esprit V8 FE  - Kelsey Hayes ABS

2005 Elise  - Kelsey Hayes ABS

2006 Exige with BOE400 357whp  - Kelsey Hayes ABS

 

My 89SE, with the Brembo Racing Brakes and the original master cylinder and vacuum servo, is by far the best of all of them!  As far as braking feel and linearity.  The original 89 and 89SE pedal feel was great, it was just that the brakes couldn't stand up to the heat on the track.

Oh and the Evora, which was pretty good!

The GM Powermaster III brakes felt horrible, though the X180-R can really stop! if you don't mind the feel.

 

 

Travis

Vulcan Grey 89SE

My Lotus Photo and Projects Album

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15 hours ago, ian29gte said:

How does it compare to the Kelsey-Hayes on the V8?

I haven't had too much time behind the wheel of an '89 SE, but both of them (89 and 96 V8), under normal driving conditions, feel like brakes on any modern car. Which the DMIII system does NOT. So in that regard, they're great. I'm real pleased with the KH3 system. 

Having said that, I have never ever *knock on wood* had to brake so hard that the ABS on any car I've ever driven activates, with the exception of winter driving in Sweden which has seen me sliding to within a millimeter of cars at junctions due to ice. I'm also not a track fiend, so my experience is very different to anyone else's. I drive my Esprits quite gently - high speeds for sure, but I don't thrash the brakes when slowing down. Sometimes I jump on the brakes in the SE to check that the ABS works. It does. Car stops quite quickly. Could stop quicker, but its from 1991 so I'm not complaining.

A pattern I have noticed though is that those who enjoy track days universally abhor ABS in any form. Seems like there's no pleasing that crowd :)

If I had to do it again though, I'd buy an '89 or '90 SE purely for the brakes (and hell, I might actually do it....)

Travis - how did you enjoy the Final Edition? Is it all that?  

Vanya Stanisavljevic '91 Esprit SE | '97 XK8

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I don't care what anyone says but the brakes on the esprit are absolute cap.  When I test drove my S4s for the first time I nearly went straight thru a roundabout.

I did everything to fix my brakes, but from the factory they are crap.  I ripped out all of the standard Abs stuff, fitted a Nissan Patrol brake servo and master cylinder.  I removed my AC pump and in its place fitted an early type vacuum pump. I switched out the standard S4s brake calipers and discs and on the front fitted S350 brake rotors and AP racing 4 pot calipers, on the rear, I've fitted S350 rotors and aftermarket 4 pot calipers on S300 brackets and kept the original brembo calipers for the hand brake. I also fitted an Audi A6 vacuum reservoir and a manual turbo boost valve with a vacuum gauge in the vacuum line to the servo, this allows me to adjust the amount of servo assist while braking. My brakes are unbelievable now compared to the original setup....and are adjustable! 

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@Vanya The FE Esprit had the "Sport Exhaust" with the center exhaust and a muffler that was just an H-pipe.  Sounded great! Best sounding Esprit!  The brakes were an on-off switch, the clutch was touchy, the throttle pedal really only worked if you really pressed hard, and then the engine would rev up suddenly, the throttle pedal may have been bent..

Didn't really get to try the suspension out. 

I liked the shifter on the 98+ Esprits! Though my 89SE is not bad, the best of all the other <98 Esprits that I have driven.

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Travis

Vulcan Grey 89SE

My Lotus Photo and Projects Album

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20 hours ago, ian29gte said:

Do you have any part numbers or model years for the bits you used, David?

I second that. And also please try to stay on topic. My favourite setup would be something with an electric vacuum pump, as I don't like to dismiss servo steering. So if anybody has done it successfully, please do us a great favour and show us your results. Some images and a parts list would be perfect. If a small guide comes next to it, even better!

 

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The middle/end of the "Calling all brake gurus" thread has MartinL listing all the parts he used to fit MR2 brakes to his Esprit.  

I don't think he ran a vacuum pump at all, just used engine vacuum with check valves and maybe an accumulator tank eventually.  

 

How do modern turbo-charged cars do it?  If we want to modernize the braking system we should be able to copy Subaru and their million WRX's.  They seem able to stop.    

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58 minutes ago, ian29gte said:

Hella do some very nice vac pumps these days. Have a browse around.

That's where I'd be headed.

When I looked at moving from mechanical to electrical vac pump I looked at the Hella ones, and felt that the volume of the Esprit servo is such that those Hella ones aren't really big enough on their own, fine until the brakes need to be applied, released and re-applied in quick succession. I've obtained one that the USA guys use when retro-fitting servos to classic trucks that didn't originally have assistance. Hella could be a good option to boost the manifold vacuum.

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Those 32s look quite good but still several seconds to get back to a decent level of assistance, longer than I think an inlet-manifold (with carbs/TBs closed) would take.

http://www.hella.com/microsite-electronics/assets/media/04_vacuum_pumps_gb_druck.pdf

 

 

Cannot find the spec of the one I purchased, but here's something that looks to be similar size.

http://sell.lulusoso.com/selling-leads/795882/12-VOLT-ELECTRIC-BRAKE-VACUUM-PUMP-FOR-ELECTRIC-VEHICLES.html

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A mate of mine fitted a Wingate (I think) one to his Chevy with a race-spec engine that never produced much brake vacuum, after he had several brown-trouser incidents without much servo assistance. I think an accumulator was part of that package.

Margate Exotics.

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