this is a concentrate of all post on the M5 board started in September 2007.
EDC Re-build DIY
Firstly, EDC rear dampers are a simple dare I say “primitive” design.
Nothing fancy about them at all.
The main cost of these units comes from the “Body” design.
This makes the non-availability of a repair kit even more annoying.
Facts I found during my “Re-build”:
With 209.000 Km use on my unit, the main Rod is in good condition.
No groves, no scares.
There are only 4 replaceable items.
1.The top Rod-seal (that’s the one that leaks)
2-3. The O-ring with the Nylon coil (Looks like a bog-standard Item to me)
4.The inner tube Ring
Once the spring is removed, replacing these 4 items should not take longer then 30 min incl. cleaning everything (I used alcohol, and then re-assembled all with a little CHM fluid.)
Special tools required: None, a vice and a Plumbers Pipe wrench was all I had to remove the top collar.
Special settings or adjustment:
To be honest, I could not think of any adjustment on the rears.
The two solenoids Valves have only 3 wires going to them.
I believe these are 12v X2, plus one Ground.
If you give 12V to the solenoids they open, cut the power and they close.
Oil viscosity, amount of Oil is set by design so nothing we could change there.
(Unlike Motorcycle forks, where you can set the damping with the oil thickness, thicker Oil = stiffer damping.)
I had a damaged rear-EDC damper with 4000 miles use in the shed one solenoid was broken due to Trolly jack slipping by the pervious owner( don’t you just love Ebay?)
Just changed the entire Rod assembly into my old body, no leaks all seams fine.
Perhaps the people that do the Re-Build could offer a seal-Set.
That could help our M5 Drivers in the US, Australia???
The fitting is NOT a big issue in my eyes.
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Quote:
Originally Posted by Sebring NL: Where did you get the seals?
I used the entire Rod- assembly from the damaged unit I had in my shed.
Even with only 4000 miles on the clock, I could imagine that the top seal worn itself in with the Rod it was fitted to originally.
By changing the lot, I have avoided a leak (older Rod with newer seal.)
If you read Mikes EDC rebuilding Thread, they can source the Original seals from boge.
(I am pretty sure, Boge uses the same seal for All there shocks with the same Rod-diameter, like some 520’s 525’s.)
So if the Re-building Company Mike found, is too busy to deal with all of us, how about offering the seals to the more “adventurous” Home mechanics like us?
At least the owners with leaking Rear Shocks could be back on the road in a short time.
And sending a few seals to Australia or NZ would be a lot cheaper as well.
Just my two cents.. Best regards RAZ
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Raz
With your comments isolated to the rears, I don't think you have
have said anything controversial.
A few have rebuilt the rears in the past in Sth America, Australia & Garcia
who is back in Nth Carolina.
Durability was still an issue from what I understand...
As oe parts, the rears last at least twice as long as the fronts.
The fronts are the main problem & always were imho.
The rods ovalise as they wear in extreme long term usage....worth checking !
Solenoids do fail on the fronts but its rare on the rears.
Damper tube bodies do rot beyond economic repair.
They can come apart quite easily, or they can be near destroyed in the dis-assembly process.
Rear damper removal is not a problem if you have the tools.
Constantly removing the dampers & putting them on & off & on off due to
short term failure is not a solution imho.
But.....
For the diy'er out there working on his own car, prepared to chance his time
on assembling the "untested as a unit" hydraulic parts is one thing.
And the best of luck to you of course.
I would not be happy to do it & I would not / could not inflict that on any of the
owners cars I work on.
I could not take on the public liability of doing it or the aggro of doing a job twice or more. Cheers Farrell
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I think this project should be regarded as a test, just as London Mike's project.
Ofcourse, nobody wants the hassle of taking them off again, but thats what testing is all about ( you are the last person Í'd have to explain that to sir )
Let's see what Raz can come up with.
When I first inquired about the EDC shocks rebuild after I concluded the SLS 3.6 rear shock wouldn't be impossible to rebuild ( my dad is an industrial constructor and can do anything hydraulic plus has access to virtually any tool or testcase) the thing I heard was from people on the board that it would be impossible to "weld " the front units shut again..
I didn't understand the construction at that time nor did I have an EDC shock handy but if this is a matter of seals and input shaft ovalising, I think there are more than enough chances to set this straight.
After all, I still haven't heard any sound reason why its any different from any other hydraulic and if the seal availability problem is solved, whats the remaining hurdle?
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Hi, Farrell, “I could not take on the public liability of doing it or the aggro of doing a job twice or more.”
Fair comment
My problem was;
On a Friday late afternoon, I discovered that my left hand rear shock was leaking like mad. With a Mot appointment firmly booked for Monday morning, my options where, shell we say “Limited”.
Holding my breath and wait for the outcome of the London Mike’s and Cyrus long-term test (My respect to these Gentleman for there dedication and effort )
Was not an option at this stage.
All I am saying is, I was in trouble and "that’s" how I got out of it!
If a £20 money outlay and 2 hours labour in total buy me 2-3 Months driving?
(Till the Test is completed and orders form us mere mortals are accepted.)
I can drive the car without causing more damage to expensive parts.
And NOT having CHM running down the Rear Disk Brake comes as a “Bonus”.
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In 1980 (my last year as an Apprentice with BMW, back home in Germany) my Master told me; “Boy, not even at the headquarters can they put a 3.0Si engine into a 525 (E12, with Carburettor )”
The only person, believing in my little project was a 15 year old school leaver who just started his apprentice ship with us at that time.
It has taken six weeks, for the two of us to build a complete wiring loom from start to finish. (Bosch’s D-Jetronic had 115 Cables and every single one is white).
The fun was short lived, as I was asked by our company director to sell my car in 1981 or at least park that “Thing” away from BMW premises.
Why?
One customer complained that an “Old” 525 form “one of the Mechanics” left his brand new 528i (E28) standing at the lights.
He demanded to have his 528i fixed or have his money back!
I had to give up working on Cars (as an occupation) almost 10 years ago (Blood Condition) now and then the “Urge” to do it my self’s still there.
Even more so, if I am told ” Boy, it can not be done”.
I personally do not feel offended by “Youngsters” (Sebring NL may forgive a 50 year old man for this expression ) if they question my “believes” or do not agree with “my way of doing things”.
After all, People like him keep the M5 alive, and if he knows something I don’t know I am more then happy to listen (and learn).
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The method of cutting below the top cap & threading is one that is fraught with tolerance issues, not least of all maintaining the correct squish along the damper axis & tight concentricity of the part to the damper rod.
I think Ray is just highllighting that as a commercial approach repeatability is key.
This takes jigs & manufacturing control process as we all know.
The main EDC project is one where we have high expectations.
What you achieved was pretty cool with such limited resource & none
of us would say otherwise
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How is the welding problem for the front struts solved in the main EDC project?
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Parts list, Prices and source of seals to repair a set of leaking rear EDC dampers
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Main Seal Kit:
First Part would be the Simrit seal kit: OMS-MR 18,00 25,30 3,0 PTFE GM201
Simrit Part No.: 24127305
(An alternative would be the HENNLICH S31-18x25.3x3.2)
Second Part would be the O-Ring : 42x3
Third Part is the Nylon spiral above the 42x3 O-Ring.
Plus the top seal (wiper ring to keep the dust out)
Parts required to re-seal both rear EDC dampers:
2X RC18-25.5-3.2-170-B BS117 £5.42 each
2X PM0425-30SP-VP £1.13 each
2X WR18-285-6MC-R £1.84 each
2X RM0420-30-N70 £0.21 each
Supplier:
FPE Ltd.
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http://www.fpe-ltd.co.uk/ <a href='http://www.fpe-ltd.co.uk/' TARGET='_blank'>http://www.fpe-ltd.co.uk/</a>
sales@ftp-ltd.co.uk
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would really like to give this a go
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Hi Raz.
I live in Australia and have an E34 M540i LE (with EDC) that has one leaky rear shock. I have recently replaced the fronts with new units. To participate in "Sportslines exchange program" will cost me around UKP300+ in freight alone plus an extra 10 days in shipping time. The rebuilt units are still less expensive than new units, but only by 30 or 40%. I'm guessing the savings are much more significant in the UK.
I am more willing to buy the seals and try to repair my rears.
Are the rear shocks gas pressurised like the fronts, or is the pressure for these shocks purely provided by the pump up front ?
When I open the bleeder valve on the LAD regulator, how much oil comes out ?
Do you think the parts you mentioned above, will fit in my shocks ?
Part Numbers for the rear shocks in my car.
37122227493
37122227494
You're talking less than UKP20 + freight + oil - 5days shipping time. You have no idea just how attractive and idea that is !
Can I please confirm that these parts are proposed for the fronts.
Quote:
Originally Posted by RAZ9922
Main Seal Kit:
First Part would be the Simrit seal kit: OMS-MR 18,00 25,30 3,0 PTFE GM201
Simrit Part No.: 24127305
(An alternative would be the HENNLICH S31-18x25.3x3.2)
Second Part would be the O-Ring : 42x3
Third Part is the Nylon spiral above the 42x3 O-Ring.
Plus the top seal (wiper ring to keep the dust out)
and these parts are the parts required for the rears
Quote:
Originally Posted by RAZ9922
Parts required to re-seal both rear EDC dampers:
2X RC18-25.5-3.2-170-B BS117 £5.42 each
2X PM0425-30SP-VP £1.13 each
2X WR18-285-6MC-R £1.84 each
2X RM0420-30-N70 £0.21 each
To check the solenoid-valve function, do the solenoids provide an audible click when power is applied to them ?
Does the EDC Computer provide 5V or 12V to control the valves ?
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Contact details typo Quote: Originally Posted by RAZ9922
Parts required to re-seal both rear EDC dampers:
2X RC18-25.5-3.2-170-B BS117 £5.42 each
2X PM0425-30SP-VP £1.13 each
2X WR18-285-6MC-R £1.84 each
2X RM0420-30-N70 £0.21 each
Supplier: FPE Ltd. www.fpe-ltd.co.uk sales@ftp-ltd.co.uk
Just in case anyone is thinking about FPE as a source of parts to solve rear EDC seal problems, there's a typo in the email address provided by RAZ9922.It should read sales@fte-ltd.co.uk just as in the URL
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He has not mentioned the parts for the fronts, that is a description of parts for the rears, the bottom actualy being a list.
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Hi Stevie
I agree that this looks like a list of parts to rebuild the top seal of a set of rear EDC shocks.
Quote:
Originally Posted by RAZ9922
Parts required to re-seal both rear EDC dampers:
2X RC18-25.5-3.2-170-B BS117 £5.42 each
2X PM0425-30SP-VP £1.13 each
2X WR18-285-6MC-R £1.84 each
2X RM0420-30-N70 £0.21 each
I agree the last 3 references in the list below, look like generic descriptions of 3 of the parts in the top seal assembly, but I'm not sure how you reach the conclusion that the information in the first 3 lines of info below "is a description of parts for the rears". I don't know much about seals so I'm starting from a low level of knowledge.
When RAZ9922 wrote "Simrit Part No. 241....." & "Hennlich S31....." & "Simrit seal kit: OMS-MR .....", aren't these references to specific parts manufactured by a specific manufacturer, rather a generic description of a seal ?
If they are generic descriptions of one of the parts in the top seal assembly, can you please help me understand what a description such as "OMS-MR 18,00 25,30 3,0 PTFE GM201" is telling me ? Are we talking about a seal made from PTFE with an OD of 25.30mm, an ID of 18.00mm with something that is 3.0mm and something else that conforms to GM201 ? As you can probably see, I'm clutching at straws, but I'd like to understand what it all means if you know and have the time to explain it.
Quote:
Originally Posted by RAZ9922
Main Seal Kit:
First Part would be the Simrit seal kit: OMS-MR 18,00 25,30 3,0 PTFE GM201
Simrit Part No.: 24127305
(An alternative would be the HENNLICH S31-18x25.3x3.2)
Second Part would be the O-Ring : 42x3
Third Part is the Nylon spiral above the 42x3 O-Ring.
Plus the top seal (wiper ring to keep the dust out)
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check the original thread here, if there are further posts, last post was 26th September 2008
http://www.m5board.com/vbulletin/e34-m5-discussion/103223-edc-re-build-diy.html