SL/R231: R231 Intermittent sound from ABC pump or Damper
#51
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AMG GTC Roadster, E63s Ed.1, M8 Comp. Coupe
Ummm Wolfman, a slightly optimistic view I think.
- Pulsation damper replacements, parts and labor, are in the $400+ range, a bit more than a flat tire I think.
- At least one member posted about a complete failure of his R231 ABC system necessitating hose and pump replacement, etc.
- A few (4-5 that I’ve seen) posts have been about the need to replace leaking ABC shocks for $$$$, as the parts are strictly MB dealer only.
- And finally, as you yourself have pointed out I believe, ABC was a not-so-common option on the R231s vs standard (or much more common) on the R230s, hence automatically a difference in the volume of complaints.
I’m certainly not complaining about the ABC in my R231 SL63 but neither have I ceased to mentally save for some expensive repairs in the months/years to come.
- Pulsation damper replacements, parts and labor, are in the $400+ range, a bit more than a flat tire I think.
- At least one member posted about a complete failure of his R231 ABC system necessitating hose and pump replacement, etc.
- A few (4-5 that I’ve seen) posts have been about the need to replace leaking ABC shocks for $$$$, as the parts are strictly MB dealer only.
- And finally, as you yourself have pointed out I believe, ABC was a not-so-common option on the R231s vs standard (or much more common) on the R230s, hence automatically a difference in the volume of complaints.
I’m certainly not complaining about the ABC in my R231 SL63 but neither have I ceased to mentally save for some expensive repairs in the months/years to come.
I'd like to call it realistic rather than optimistic
![Wink](https://mbworld.org/forums/images/smilies/wink.gif)
We have had R230's from the time they came out; same with the R231's so there is a bit of experience with both over the last twenty years.
Even though I have considered the ABC much improved (better yet on the facelift model) the R231 has proven to be more trouble-free than anticipated IMO. If you have trouble finding barely a handful of issues over 9 years that is statistically nothing.
And there are thousands of SL's with ABC in the US including all AMG SL's. In Canada every SL has it. It isn't as rare as you might think.
In terms of cost, a flat tire (Michelin PSS or PS4s) with mount/balance/disposal will cost well above $400 so quite comparable. The struts are pricey only because no rebuild are available (consider that a sign of rarity). Like other suspension components it is also considered a wear/tear part. Cost is relative though; we had a couple couple damaged CCB rotors on our E63s, the replacement costs of those were an eye watering $9.5k - for 2 brake rotors! Lucky it was recognized as a manufacturing flaw as those are definitely considered wear/tear parts and not covered by warranty.
In the end of course any complex mechanical system will eventually fail; the difference between reliable and unreliable is when and how frequent this occurs. So far I like the odds on ABC but anybody owning the SL or any other $100k car without warranty has to set aside an appropriate maintenance/repair budget.
Last edited by Wolfman; 10-16-2021 at 01:20 AM.
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allfortheunion (10-16-2021)
#52
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1986 560SL, 2017 E300, 2018 Sl550, 2020 E350
OK here is my 2 cents Re the ABC system:
I'm a former Submarine Nuclear Power Plant Engineer so well familiar with mechanical systems and hydraulics for sure.
Let me start by saying I am now on the 2'nd SL550 with ABC (1'st was a 2015 and now a 2018); love the car, love the performance of the ABC so much that I bought out the lease on the 2018 and plan to keep it like the 1986 560SL with 32K original miles that sits beside the SL550).
"0" issues with the 2015 that I had for 3 yrs and 30K some miles.
Had "minor" leak from R rear strut on the 2018 1 yr in @ 5K mi. I believe the leak was caused by running over an abrupt 2" step in road bed under construction (paving crew did not provide a taper between milled roadbed and the new top coat) that obviously introduced a rapid hydraulic shock to the system that in my opinion weeded out a weak component (the strut that developed the minor leak). Leaking strut was replaced under warrantee complete system check including rodeo performed and all other components shown to be OK......so....in my opinion this was a good test of the system and the R rear strut that was an "infant mortality" was wedded out.
Maybe my failure was similar to the one other strut replacement I know of...if so understandable and again weeds out infant mortalities.
Sure would like to hear from MB as to their suggestions for ABC maintenance but, no where to be found so we on our own.
Back to the ABC and R231s:
As Wolfman has said the R231 ABC system is greatly improved over the R230; here are just a few of the improvements:
1) Hoses moved from areas of hi heat (moved from under the engine that also required engine removal for replacement).
2) Hoses, valve block & accumulators location and assembly redesigned for ease of replacement of components (assembly tilts down for component replacement w/o need to remove lines so less expensive labor vs R230)..
3) Valve block valve seals using better material.
4) Struts redesigned (this reason for not yet being able to purchase rebuilt units as not enough failed units available for rebuild).
5) ABC filter media redesigned to filter out smaller particulates
6) Fluid canister redesign to preclude owner and dealer/service contamination.
7) Pump pulsation damper relocated to immediate pump discharge to smooth out high pump discharge pressure and respond to system surges vs letting the pump see high system surges (increases pump reliability) BUT....by placing the pulsation damper on top of the engine and subjecting it to high ambient heat the life of the rubber diaphragm in the damper (accumulator) is affected causing I believe need to look at the pump pulsation damper as a maintenance part that should be replaced as a PM. My belief seems supported by the few reports of need for pulsation damper replacements we have seen. Based on this I plan to replace mine as soon as I feel vibrations or maybe @ 50K miles or 7 yrs as a precaution to insure it is operating as designed.
8) Important to watch fluid color and fluid level as both are tell tales to proper system operation and longevity:
a)Insure you know how to check fluid level as it will tell you a lot . MAKE SURE you clean the area around the dip stick before checking so you are sure contaminates are not being introduced into the canister !
Fluid level is different with engine running vs when engine off.....with engine running level on the dip stick is the lower mark..... lower than when engines is shut down as the system is pressurized when running and the 3 accumulators (F, R and Return) are pressurized with pump providing pressurized fluid compressing the diaphragms in the accumulators against the nitrogen charge thereby providing the give and take needed as the struts rise and fall...BUT when the engine is shut down the nitrogen in the accumulators displaces the fluid back to the ABC canister raising the level.
b) If fluid level was OK but now down it means you have a leak somewhere (easily visible by under car view) but, if no leak then LIKELY is sign of an accumulator diaphragm leaking internally AND putting strain on the system by not moving sufficiently to allow design give and take that will lead to failed seals in the struts or leaking/blown supply lines and or stressed/failed pump
SO.......Really important to do the following:
1)Check periodically or have the MB dealer check ea service for fluid level AND color of the fluid
Fluid level falling requiring adding fluid but no signs of leaks under the car indicates likely accumulator internal diaphragm leak and as the accumulator not operating as designed will put stress on all ABC components.
Fluid color is a sign of deterioration of rubber in the hoses or accumulators diaphragms (it's the rubber deterioration that turns the color from clear green to dark green or blackish) and I believe as long as fluid level is constant (no need to add) that just a fluid and filter change is all needed.
Bottom line:
If I have no fluid drop but, color change I will change fluid and filter.
BUT
If I see fluid drop and no under car leaks I will suspect an accumulator failing and probably change all accumulatos.
Notwithstanding the above I will swap out the pump pulsation damper at 50K miles as cheap insurance.
Also understandable that over time the accumulators will need replacement (the rubber diaphragms will leak internally and lack of proper accumulator function will put strain/shock on all ABC component accelerating potential for leaks/failures) so monitoring fluid level is important.....insure your dealer tells you if need to add fluid as it is sign of accumulator failure.
FYI:....If when the dip stick is pulled and if there is a rush of air could mean that one of the accumulator diaphragm has failed and the nitrogen charge in the accumulator has expelled into the system and into the ABC tank so when pulling the sealed dip stick the nitrogen is expelled.....just another thing to look for
Bottom line: The system is well designed, operates very well and performance of the car with it is so much better than without BUT, like anything complex it will need observation and maintenance (better yet preventative maintenance that will be less expensive that waiting until failures. As I have said the system on our R231s has been improved such that the preventative maintenance of fluid/filter, pump pulsation damper and when needed the 3 accumulators will be much less expensive than was the case with R230s
I'm a former Submarine Nuclear Power Plant Engineer so well familiar with mechanical systems and hydraulics for sure.
Let me start by saying I am now on the 2'nd SL550 with ABC (1'st was a 2015 and now a 2018); love the car, love the performance of the ABC so much that I bought out the lease on the 2018 and plan to keep it like the 1986 560SL with 32K original miles that sits beside the SL550).
"0" issues with the 2015 that I had for 3 yrs and 30K some miles.
Had "minor" leak from R rear strut on the 2018 1 yr in @ 5K mi. I believe the leak was caused by running over an abrupt 2" step in road bed under construction (paving crew did not provide a taper between milled roadbed and the new top coat) that obviously introduced a rapid hydraulic shock to the system that in my opinion weeded out a weak component (the strut that developed the minor leak). Leaking strut was replaced under warrantee complete system check including rodeo performed and all other components shown to be OK......so....in my opinion this was a good test of the system and the R rear strut that was an "infant mortality" was wedded out.
Maybe my failure was similar to the one other strut replacement I know of...if so understandable and again weeds out infant mortalities.
Sure would like to hear from MB as to their suggestions for ABC maintenance but, no where to be found so we on our own.
Back to the ABC and R231s:
As Wolfman has said the R231 ABC system is greatly improved over the R230; here are just a few of the improvements:
1) Hoses moved from areas of hi heat (moved from under the engine that also required engine removal for replacement).
2) Hoses, valve block & accumulators location and assembly redesigned for ease of replacement of components (assembly tilts down for component replacement w/o need to remove lines so less expensive labor vs R230)..
3) Valve block valve seals using better material.
4) Struts redesigned (this reason for not yet being able to purchase rebuilt units as not enough failed units available for rebuild).
5) ABC filter media redesigned to filter out smaller particulates
6) Fluid canister redesign to preclude owner and dealer/service contamination.
7) Pump pulsation damper relocated to immediate pump discharge to smooth out high pump discharge pressure and respond to system surges vs letting the pump see high system surges (increases pump reliability) BUT....by placing the pulsation damper on top of the engine and subjecting it to high ambient heat the life of the rubber diaphragm in the damper (accumulator) is affected causing I believe need to look at the pump pulsation damper as a maintenance part that should be replaced as a PM. My belief seems supported by the few reports of need for pulsation damper replacements we have seen. Based on this I plan to replace mine as soon as I feel vibrations or maybe @ 50K miles or 7 yrs as a precaution to insure it is operating as designed.
8) Important to watch fluid color and fluid level as both are tell tales to proper system operation and longevity:
a)Insure you know how to check fluid level as it will tell you a lot . MAKE SURE you clean the area around the dip stick before checking so you are sure contaminates are not being introduced into the canister !
Fluid level is different with engine running vs when engine off.....with engine running level on the dip stick is the lower mark..... lower than when engines is shut down as the system is pressurized when running and the 3 accumulators (F, R and Return) are pressurized with pump providing pressurized fluid compressing the diaphragms in the accumulators against the nitrogen charge thereby providing the give and take needed as the struts rise and fall...BUT when the engine is shut down the nitrogen in the accumulators displaces the fluid back to the ABC canister raising the level.
b) If fluid level was OK but now down it means you have a leak somewhere (easily visible by under car view) but, if no leak then LIKELY is sign of an accumulator diaphragm leaking internally AND putting strain on the system by not moving sufficiently to allow design give and take that will lead to failed seals in the struts or leaking/blown supply lines and or stressed/failed pump
SO.......Really important to do the following:
1)Check periodically or have the MB dealer check ea service for fluid level AND color of the fluid
Fluid level falling requiring adding fluid but no signs of leaks under the car indicates likely accumulator internal diaphragm leak and as the accumulator not operating as designed will put stress on all ABC components.
Fluid color is a sign of deterioration of rubber in the hoses or accumulators diaphragms (it's the rubber deterioration that turns the color from clear green to dark green or blackish) and I believe as long as fluid level is constant (no need to add) that just a fluid and filter change is all needed.
Bottom line:
If I have no fluid drop but, color change I will change fluid and filter.
BUT
If I see fluid drop and no under car leaks I will suspect an accumulator failing and probably change all accumulatos.
Notwithstanding the above I will swap out the pump pulsation damper at 50K miles as cheap insurance.
Also understandable that over time the accumulators will need replacement (the rubber diaphragms will leak internally and lack of proper accumulator function will put strain/shock on all ABC component accelerating potential for leaks/failures) so monitoring fluid level is important.....insure your dealer tells you if need to add fluid as it is sign of accumulator failure.
FYI:....If when the dip stick is pulled and if there is a rush of air could mean that one of the accumulator diaphragm has failed and the nitrogen charge in the accumulator has expelled into the system and into the ABC tank so when pulling the sealed dip stick the nitrogen is expelled.....just another thing to look for
Bottom line: The system is well designed, operates very well and performance of the car with it is so much better than without BUT, like anything complex it will need observation and maintenance (better yet preventative maintenance that will be less expensive that waiting until failures. As I have said the system on our R231s has been improved such that the preventative maintenance of fluid/filter, pump pulsation damper and when needed the 3 accumulators will be much less expensive than was the case with R230s
Last edited by steve sl550; 10-16-2021 at 09:08 PM. Reason: adding
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#54
Pulsation Damper Replacement
Hey guys, just want to let you all know I also have a 2013 SL63 AMG and I just replaced the pulsation damper yesterday. only 25K miles on mine. I have also already had the ABC pump replaced but luckily under warranty.
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billvp218 (10-25-2021)
#55
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1986 560SL, 2017 E300, 2018 Sl550, 2020 E350
FWIW the Hd Mechanic at my dealership (one of the largest in Massachusetts) told me that of all the cars with ABC (SLs and others) that they have only seen 2 failures BOTH due to hitting a large pot hole).
1) Small strut leak
2) Pump pulsation damper blew open
Nothing else to report.
So.....I stand by my email above of 10/16 as to how I will handle my ABC system.
1) Small strut leak
2) Pump pulsation damper blew open
Nothing else to report.
So.....I stand by my email above of 10/16 as to how I will handle my ABC system.
#56
Super Member
Ok, but this guy had the ABC pump previously replaced and then the damper....could that be related to the same incident.....
#57
2013 SL63 AMG ABC leak?, pump noise is getting louder
Hi All, I'm new to this forum, I'm in Toronto Canada. 2013 SL63 AMG + performance package 75K
Mechanic noticed a oil stain at the bottom of the left front strut. Shortly there after 200 km, some sort of pump noise started at idling, and is progressively getting louder, and now I can hear it while driving.
Mechanic found the fluid in the ABC system could not be seen on the dipstick. He says he had topped it up a week or two prior when he saw the a fluid sweat at the bottom of the LF strut. The fluid was topped up. The pump type noise is getting louder.
Q ?
Can I drive the car to the dealer approx 25 KM away without damaging anything?
The car has not dropped so I can I take it that the struts are not the issue?
Does the LF strut with the oil sweat need to be replaced?
Reading this thread I am assuming that it likely can be a Pulsation Damper?
Any thoughts that the resvoir or pump is damaged, and can I drive the car to the dealer/mechanic shop without causing further damages ?
Any insight would be appreciated.
Mechanic noticed a oil stain at the bottom of the left front strut. Shortly there after 200 km, some sort of pump noise started at idling, and is progressively getting louder, and now I can hear it while driving.
Mechanic found the fluid in the ABC system could not be seen on the dipstick. He says he had topped it up a week or two prior when he saw the a fluid sweat at the bottom of the LF strut. The fluid was topped up. The pump type noise is getting louder.
Q ?
Can I drive the car to the dealer approx 25 KM away without damaging anything?
The car has not dropped so I can I take it that the struts are not the issue?
Does the LF strut with the oil sweat need to be replaced?
Reading this thread I am assuming that it likely can be a Pulsation Damper?
Any thoughts that the resvoir or pump is damaged, and can I drive the car to the dealer/mechanic shop without causing further damages ?
Any insight would be appreciated.
#58
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1986 560SL, 2017 E300, 2018 Sl550, 2020 E350
As I understand:
If you haven't had any "dash alerts" and your suspension hasn't dropped I think you are OK to get to the dealer.
BUT
Based on your explanation I suspect you have 2 issues:
1) Noise
Probably due to failure of the Pump Pulsation Damper (easy replacement as it is right behind the pump on top of the engine).
2) Drop in fluid level without any major strut leak (only dampness on 1 strut)
Most likely caused by accumulator loosing charge and likely the front accumulator ?
If the struts not leaking this is the only place the fluid drop could go (to fill the space in the accumulator that was filled with nitrogen)
Good thing is that the R231 is a lot easier to replace the accumulators than the older R230 as the valve/accumulator assembly can be hinged down to remove the accumulator without disconnecting any lines.
PS: Do you remember going over any major potholes or large steps in the roadbed. From what I understand only issues my dealer has advised of (only 2) involved a car hitting a major pothole that put severe stress on the system and caused a Pump pulsation damper to destroy (smallest accumulator so it failed first)...the other case was car with really small drip from strut...again both caused by the car hitting a major pot hole.
Please keep us informed !
Tx, Steve
If you haven't had any "dash alerts" and your suspension hasn't dropped I think you are OK to get to the dealer.
BUT
Based on your explanation I suspect you have 2 issues:
1) Noise
Probably due to failure of the Pump Pulsation Damper (easy replacement as it is right behind the pump on top of the engine).
2) Drop in fluid level without any major strut leak (only dampness on 1 strut)
Most likely caused by accumulator loosing charge and likely the front accumulator ?
If the struts not leaking this is the only place the fluid drop could go (to fill the space in the accumulator that was filled with nitrogen)
Good thing is that the R231 is a lot easier to replace the accumulators than the older R230 as the valve/accumulator assembly can be hinged down to remove the accumulator without disconnecting any lines.
PS: Do you remember going over any major potholes or large steps in the roadbed. From what I understand only issues my dealer has advised of (only 2) involved a car hitting a major pothole that put severe stress on the system and caused a Pump pulsation damper to destroy (smallest accumulator so it failed first)...the other case was car with really small drip from strut...again both caused by the car hitting a major pot hole.
Please keep us informed !
Tx, Steve
Last edited by steve sl550; 10-28-2021 at 09:30 AM. Reason: addition
#60
Fluid and noise
Hello ACESRWILD,
NewBrunswick Canada here. My 2013 SL550 (purchased last year from the Toronto area) started with a noise/vibration from left front area which travelled through steering wheel. Had it diagnosed as left front strut leak. Noise is from air in system. I have a friend with a scan tool which can perform the "rodeo" program which removes the air. I put it up on a hoist to do an oil/filter change before storing it for the winter and confirmed the leak. Not hard to tell. I will be looking for a strut over the winter and replace it in the spring. It doesn't look very challenging.
Does anyone know what kind of hydraulic fluid the 2013 r231and up ABC system takes? Is it different from the previous r230 models?
NewBrunswick Canada here. My 2013 SL550 (purchased last year from the Toronto area) started with a noise/vibration from left front area which travelled through steering wheel. Had it diagnosed as left front strut leak. Noise is from air in system. I have a friend with a scan tool which can perform the "rodeo" program which removes the air. I put it up on a hoist to do an oil/filter change before storing it for the winter and confirmed the leak. Not hard to tell. I will be looking for a strut over the winter and replace it in the spring. It doesn't look very challenging.
Does anyone know what kind of hydraulic fluid the 2013 r231and up ABC system takes? Is it different from the previous r230 models?
#61
2013 MN SL63 AMG ABC LF Strut Issues/ Pulsation Damper R231
Hello and thank you for your response.
I had MB do a diagnostic on the noise and it turns out it is from a failed pulsation damper on the hydraulic ABC suspension system and not a leaking strut. Part is $619. Check out you tube on this subject.
Also just a FYI, I found a company in Florida called RMT rebuilders 954 934 9595 they rebuild hydraulic & air struts. They may be able to help you. To Rebuild a strut they charge $299 If I remember correctly. A lot cheaper than than the cost of a new one. In my case they had no 2013 rebuilt ones yet, I was going to send them my broken strut for them to rebuild. Add up all the costs of shipping fees USA exchange etc, it is still cheaper than buying one at The MB dealership.
Hope This helps
Joe In Toronto Canada
I had MB do a diagnostic on the noise and it turns out it is from a failed pulsation damper on the hydraulic ABC suspension system and not a leaking strut. Part is $619. Check out you tube on this subject.
Also just a FYI, I found a company in Florida called RMT rebuilders 954 934 9595 they rebuild hydraulic & air struts. They may be able to help you. To Rebuild a strut they charge $299 If I remember correctly. A lot cheaper than than the cost of a new one. In my case they had no 2013 rebuilt ones yet, I was going to send them my broken strut for them to rebuild. Add up all the costs of shipping fees USA exchange etc, it is still cheaper than buying one at The MB dealership.
Hope This helps
Joe In Toronto Canada
#63
I don't have a pic, but the one damper in question that failed was located on the back of hydraulic main valve for the suspension system. It is round and looks like a black soft ball size part.
MB diagnosed it.
Another mechanic wanted to replace the strut.
Approx $700 cdn
#64
Junior Member
Thread Starter
Pulsation damper 2013 SL 550 R231
Hello Issacsim,
I don't have a picture but it should be an easy fix standing up in front of the car.
The price at the dealer is $ 395cdn plus labor. The part number is 1000 466 04 00 87 it is located right in front of you when you are facing the engine bay, top front and center of the engine. It is attached behind to the hydraulic pump. It looks like a small black oil filter about 3˝ x 3˝ inches with a round top.
I don’t know if this applies to all damper changes but in my case, it took 2 mechanics to pry it loose with a lot of muscle and chain locking pliers because of its awkward position that does not give you much room to maneuver the pliers also mine was seized to the pump, after it just unscrews like an oil filter.
Good luck
Regards
SLDOUG
I don't have a picture but it should be an easy fix standing up in front of the car.
The price at the dealer is $ 395cdn plus labor. The part number is 1000 466 04 00 87 it is located right in front of you when you are facing the engine bay, top front and center of the engine. It is attached behind to the hydraulic pump. It looks like a small black oil filter about 3˝ x 3˝ inches with a round top.
I don’t know if this applies to all damper changes but in my case, it took 2 mechanics to pry it loose with a lot of muscle and chain locking pliers because of its awkward position that does not give you much room to maneuver the pliers also mine was seized to the pump, after it just unscrews like an oil filter.
Good luck
Regards
SLDOUG
#66
Junior Member
Thread Starter
If your symptoms are like the one, I described it is the pulsation damper.
Just bend down a bit from the centre front bumper and you will see it.
It is located between the 2 turbo pipes about 1 foot from your fan housing, you will have to remove your air filter housing.
The hydraulic pressure is very high. I believe it's around 2000psi. I do not remember if they had to lower it to replace the damper.
Perhaps someone on this blog can advise you on that
Good luck
SLDOUG
#68
I dont have a pic but as it turns out the damper may not be the issue. I put it up on a hoist and the front left ABC strut is leaking. I will replace that first then perform a rodeo to get the air out and see if the noise/vibration is gone. There are two dampers, one under the hood center front behind the pump and the other is at the rear of the left front fender attached to the ABC valve block. Now Im trying to find a good used ABC strut in eastern Canada. New is $$$$$
#69
Pulsation damper
Hello all,
Progress is slow because of priorities but, I have replaced the leaking strut with a used one and have cured the leak. Topped up fluid (from dealer) and completed rodeo twice to be sure. Vibration/growl noise more when hot and lower rpm still happening. I noticed on scan tool that it only happens when pressure drops to 160 (bar? Psi? Can’t remember) After reading this whole thread a couple of times I am going to replace the damper on the pump and see what happens. Even though the noise is in the lower front fender area.
Progress is slow because of priorities but, I have replaced the leaking strut with a used one and have cured the leak. Topped up fluid (from dealer) and completed rodeo twice to be sure. Vibration/growl noise more when hot and lower rpm still happening. I noticed on scan tool that it only happens when pressure drops to 160 (bar? Psi? Can’t remember) After reading this whole thread a couple of times I am going to replace the damper on the pump and see what happens. Even though the noise is in the lower front fender area.
#70
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1986 560SL, 2017 E300, 2018 Sl550, 2020 E350
Let us know how the new pulsation dampener works out.
I think the fact that you hear noise from the dampener in the fender area as opposed to hearing it from front of the engine is because the noise at the dampener is masked by the engine noises at the front of the engine.
The noise in the fender area is likely sympathetic noise traveling through the piping and is more noticeable in the fender area as there is less engine noise in that location.
try putting a stethoscope or long screwdriver on the dampener and I bet you hear the noise there.
let us know
Tx
I think the fact that you hear noise from the dampener in the fender area as opposed to hearing it from front of the engine is because the noise at the dampener is masked by the engine noises at the front of the engine.
The noise in the fender area is likely sympathetic noise traveling through the piping and is more noticeable in the fender area as there is less engine noise in that location.
try putting a stethoscope or long screwdriver on the dampener and I bet you hear the noise there.
let us know
Tx
#72
That's the fix!
Firstly, many thanks to steve sl550. The noise was indeed from the pulsation damper at the pump. The part number was also correct (there are actually multiple numbers as it has been changed up a number of times). It was a simple replacement. Using a scan tool release pressure, remove bracket bolts for a little elbow room and replace damper. Using scan tool complete a rodeo event and you are finished. I have put a few klm on it just to make sure. Not a sound.
Oh and the used strut is continuing to do its duty with no adverse effects.
Thanks again,
FirstBenz
Oh and the used strut is continuing to do its duty with no adverse effects.
Thanks again,
FirstBenz
#73
Hi guys,
Last week when i started the car after work I had the known grinding / howling noise from 1000-2000 rpm. Nowing directly the issue comes from pulsation damper and searched the part in internet. Taking a 14 wrench it was a 5 minutes job to replace the damper and....noise disappeared. Strike!
So if you have this problem then please invest five minutes instead bothering a mechanic and paying a hell of a money![Smilie](https://mbworld.org/forums/images/smilies/smile.gif)
Now I have a second problem. Car has only 35k of miles but I have a green smear all around the pump. So tomorrow I will remove the serpentine belt and the ABC pulley and inspect the pulley inside. If green smear is inside I will directly empty the reservoir and remove the pump. We have a special company here in Germany that repairs all pumps and you get really a quality item back. That costs me about 400 bugs. (much better than paying 3000 at Mercedes). When reinstalling the pump I use a pressure pump to put some pressure to the system before starting the engine. This is absolutely obligatory as the pump is not able to suction the oil itself initially and it would run dry. There is a video on youtube how to do it from the mentioned company.
But regarding the broken pulsation damper I expect the other accumulators will follow soon. And regarding the big number of sl500 with ABC driving around in US, has someone additional experience in sliding out the front and back valve block for replacing the accumulators?
I can do everything myself I guess but I would like to avoid to dismount the pressure line to the the dampers as this means to recalibrate the system afterwards with Star Diagnosis that I do not own. Did anybody manage to replace the accumulators without removing the pressure hoses?
Thanks a lot and regards,
Metsche
Last week when i started the car after work I had the known grinding / howling noise from 1000-2000 rpm. Nowing directly the issue comes from pulsation damper and searched the part in internet. Taking a 14 wrench it was a 5 minutes job to replace the damper and....noise disappeared. Strike!
So if you have this problem then please invest five minutes instead bothering a mechanic and paying a hell of a money
![Smilie](https://mbworld.org/forums/images/smilies/smile.gif)
Now I have a second problem. Car has only 35k of miles but I have a green smear all around the pump. So tomorrow I will remove the serpentine belt and the ABC pulley and inspect the pulley inside. If green smear is inside I will directly empty the reservoir and remove the pump. We have a special company here in Germany that repairs all pumps and you get really a quality item back. That costs me about 400 bugs. (much better than paying 3000 at Mercedes). When reinstalling the pump I use a pressure pump to put some pressure to the system before starting the engine. This is absolutely obligatory as the pump is not able to suction the oil itself initially and it would run dry. There is a video on youtube how to do it from the mentioned company.
But regarding the broken pulsation damper I expect the other accumulators will follow soon. And regarding the big number of sl500 with ABC driving around in US, has someone additional experience in sliding out the front and back valve block for replacing the accumulators?
I can do everything myself I guess but I would like to avoid to dismount the pressure line to the the dampers as this means to recalibrate the system afterwards with Star Diagnosis that I do not own. Did anybody manage to replace the accumulators without removing the pressure hoses?
Thanks a lot and regards,
Metsche
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Tommyboy928 (04-24-2023)
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AMG GTC Roadster, E63s Ed.1, M8 Comp. Coupe
Hi guys,
Last week when i started the car after work I had the known grinding / howling noise from 1000-2000 rpm. Nowing directly the issue comes from pulsation damper and searched the part in internet. Taking a 14 wrench it was a 5 minutes job to replace the damper and....noise disappeared. Strike!
So if you have this problem then please invest five minutes instead bothering a mechanic and paying a hell of a money![Smilie](https://mbworld.org/forums/images/smilies/smile.gif)
Now I have a second problem. Car has only 35k of miles but I have a green smear all around the pump. So tomorrow I will remove the serpentine belt and the ABC pulley and inspect the pulley inside. If green smear is inside I will directly empty the reservoir and remove the pump. We have a special company here in Germany that repairs all pumps and you get really a quality item back. That costs me about 400 bugs. (much better than paying 3000 at Mercedes). When reinstalling the pump I use a pressure pump to put some pressure to the system before starting the engine. This is absolutely obligatory as the pump is not able to suction the oil itself initially and it would run dry. There is a video on youtube how to do it from the mentioned company.
But regarding the broken pulsation damper I expect the other accumulators will follow soon. And regarding the big number of sl500 with ABC driving around in US, has someone additional experience in sliding out the front and back valve block for replacing the accumulators?
I can do everything myself I guess but I would like to avoid to dismount the pressure line to the the dampers as this means to recalibrate the system afterwards with Star Diagnosis that I do not own. Did anybody manage to replace the accumulators without removing the pressure hoses?
Thanks a lot and regards,
Metsche
Last week when i started the car after work I had the known grinding / howling noise from 1000-2000 rpm. Nowing directly the issue comes from pulsation damper and searched the part in internet. Taking a 14 wrench it was a 5 minutes job to replace the damper and....noise disappeared. Strike!
So if you have this problem then please invest five minutes instead bothering a mechanic and paying a hell of a money
![Smilie](https://mbworld.org/forums/images/smilies/smile.gif)
Now I have a second problem. Car has only 35k of miles but I have a green smear all around the pump. So tomorrow I will remove the serpentine belt and the ABC pulley and inspect the pulley inside. If green smear is inside I will directly empty the reservoir and remove the pump. We have a special company here in Germany that repairs all pumps and you get really a quality item back. That costs me about 400 bugs. (much better than paying 3000 at Mercedes). When reinstalling the pump I use a pressure pump to put some pressure to the system before starting the engine. This is absolutely obligatory as the pump is not able to suction the oil itself initially and it would run dry. There is a video on youtube how to do it from the mentioned company.
But regarding the broken pulsation damper I expect the other accumulators will follow soon. And regarding the big number of sl500 with ABC driving around in US, has someone additional experience in sliding out the front and back valve block for replacing the accumulators?
I can do everything myself I guess but I would like to avoid to dismount the pressure line to the the dampers as this means to recalibrate the system afterwards with Star Diagnosis that I do not own. Did anybody manage to replace the accumulators without removing the pressure hoses?
Thanks a lot and regards,
Metsche