W215 valve block DIY repair (Surrey/Hampshire)

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That's great to hear. I have had a similar experience with 4 Indies so far even though they mention the intention to always repair first on the phone, just wasted my time (and theirs I guess).

Agreed, I understand very well that a rebuild and clean has no guarantee but at the fraction of the cost, I'd like to try and a second hand unit for £600 could be just as clogged up so that does not appeal to me.

Although the newer versions can't be repaired, have they been more reliable?
 
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Both the new blocks and the old ones are vulnerable to contamination flowing through with the oil. Seals get jammed and worn and passages get clogged. The Holy Grail for a trouble free hydraulic system is ensuring that the oil is maintained CLEAN.
CHF11s hydraulic oil is Hygroscopic, having the ability to attract and hold water molecules (same as brake fluid). When the Accumulators that support the system malfunction, the diaphragms within them rupture leaking Nitrogen gas into the oil and minute particles of the rubber diaphragms. Changing the oil and filter at least once a year will keep your pump, valves and struts healthy.

I currently run and own a cl500 and with all my hydraulic oil changes, I have also added 'XADO EX120 Revitalizant' which is specially designed for Revitalization of Hydraulic Equipments, Power Steering System and so forth. A New Metalloceramics Coating is formed on the friction pairs. As a result, the renovated unit surpasses the new one with its performance characteristics and is guaranteed to serve 2 – 4 times longer. (XADO 1 Stage Engine Revitalizant engine treatment used in my engine).

***If any one has a faulty 'NEW STYLE Valve Block' 2005 upwards, send it to me an I will dissect it and let you know if they can be repaired. My suspicions are that they can be fixed. Its all about expertise skill tricks & experience***
 
Crown , I have added your email to my contacts for when I get myself a CL600.
 
CL600 . . . way to go French . . . vroooom!!!
You will be spending more than the average CL(500) buyer so check it out with a toothpick . . . and especially above 100 kph, no matter what the owner says - STABILITY must be spot on - then come to a hard stop to make sure that there is no vibration coming through the wheels.
You're paying for POWER, its got to be good. You should I guess know about it's hydraulics. Clean Oil, No Leaks and No corrosion on the pipes (especially the rear left - its the hardest to change), ride smooth as silk.
All the best.
 
I have rebuilt the front valve block about 5-6 on my SL55 but have not been successful, it still sags on the front passenger side just the same. It doesn't drop all the way down but leaves about a finger between the tyre & fender after a day or two, which should be around three fingers at rest on mine. So, still figuring out the next course of action.

Having said that, I would still recommend giving it a go, especially with assistance & knowledge on this thread/forum, as I have heard many successful attempts. One important issue are the seals. I rebuilt 2 blocks for mine(managed to get another defective one) & feel that I made some progress when a kind man who rebuilds them in Texas sent me some of his o-rings instead of what I was buying locally. He has re-built over 20 blocks successfully.

Mysteriously, when I rebuilt both blocks, always the same side sags. Only difference, it got worse with the other block & with the seals I was buying locally(here in Malta). Crownhouse; where can I buy that fluid Revitilizant you mention; do you think this could help??

Apologies for any hi-jacking of the thread; just sharing & learning dde0a
 
In your case, there is probably still leakage from your valve block and this is down to the 'O' ring seals. If the correct sizes (and correct materials) of o-ring are not used then there will be seepage on the retaining valves.

But there could still be other issues which I will continue to explain.

When fitting new seals, they must be put back in the correct positions. On the retaining solenoid (the smaller of the two), the o-ring that sits near to the solenoid body must be ahead (in front) of the retaining/spacer nylon washer.
The o-ring that sits farthermost from the solenoid body, must be between two retaining/spacer nylon washers. In some forums, I have seen where the nylon spacer washers have been removed all together and the o-rings have been doubled up.
I have never done this before, so I can not tell you if this method works. The nylon washers serve a very simple but complex purpose - they allow the o-rings to deform to a certain shape and position so as to create maximum seal under the pressures they are subject to.
Another thing to note, are the springs at the end of the retaining solenoid. Check both are the same height and of similar compression strength. When the solenoid/spring is put back into the valve body, they must retain their position on top of the solenoid shaft.
You did mention that it is always one side that drops. Here is a simple test that will help you diagnose your issue.
* Remove the valve block and inspect internally for cracks (very unlikely).
* If there are no apparent cracks , then
* Switch the solenoids positions (Left to right and right to left)
* Solenoid on the left will now be on the right.
* BUT DO NOT SWITCH THE WIRES keep them in their original positions.
* With the solenoids switched and the valve-block back in position
* Observe which side starts to sag.
* If the opposite side now starts to sag - the problem is with the solenoid and/or seal.
* If the same side still sags after you have switched the solenoids then there may be a problem with the electrical feed to that side.
* This where you will definitely need MB STAR DIAGNOSTICS and not forums or people like me talking.

For the problems you are having, 'XADO EX120 Revitalizant' will not help at the moment. However if you continue reading, I have explained it benefits and its use.

With regards to 'XADO EX120 Revitalizant' this is what it will do.
The Revitalizant coats the contact metal parts of the pump with a Metalloceramics Coating that withstands friction degradation of parts.
With this in your oil system, it should then increase the life of your pump (PROVIDE THAT YOUR OIL IS NOT DIRTY).
Another added benefit, is if for some reason you loose all your oil (like in a pipe burst) on the highway, the Metalloceramics Coating will give you enough protection to coast your car to a standstill and park in the lay-by without blowing your pump (I reckon a distance of 1/2 a kilometer).

'XADO EX120 Revitalizant' is available on e-Bay.

Please let me know how you get on with your issues and I will be glad to advice and help any way I can. ALL THE BEST.
 
To my recollection, I changed the o-rings & kept each location as I stripped one at a time for reference. Did also check the solenoids work electricity & springs etc as I was corresponding with the guy in Texas. Checked the metal to metal seals & could not see any defects.

After being unsuccessful & although I don't give up that easily, I felt that I wasn't too comfortable on taking the valve block on/off the car so many times due to causing something else to fail. So, now I have bought another used one from Dronsfield & waiting for arrival.. Will try this & replace the fluid/filter again as it will soon be a year since the last change.

However, I have thought of alternating the small solenoids. I do intend on rebuilding them here in Malta so I'm not done yet.

My question would be, if not the solenoid, how do you suggest an electrical issue? Electrically, it is basically a shut off valve, electrically charged it opens, then when no power, the spring compresses the plunger back to seal metal to metal. Is there some other electrical issue than can cause it not seal?
 
Before doing anything further, I STRONGLY SUGGEST that you get a liter of CHF11s and bleed the sagging side from the bleed nipples.
Raise the car to its highest position and jack the car off the ground putting all four sides on jack stands (all four wheels off the ground).

PLEASE BE SAFE AT ALL TIMES. THINK SAFE. WORK SAFE.

With all four wheel off the ground, Charge the system by using the level switch - lowest position to highest position to lowest position and back to highest position.
Leave it in the highest position and with the car still running, slightly open the bleed nipple on the offending side (as is done when bleeding brakes) and observe for air discharge or foam discharge.

* VERY IMPORTANT* I would connect a transparent hose to the nipple head first with the other end into a clean container. The hose makes it easier to see if air is in the system and prevents the oil from squirting every where. The container checked after will also show if there are solid contaminants in the system.

*VERY IMPORTANT* Bleeding the nipple is a two (2) spanner job. One spanner to secure the body of the nipple and another spanner (bleed nipple/crowfoot spanner) to open the nipple head. This is important because the spanner used to secure the nipple body prevents twisting which in turn prevents the hose connection to it from shearing.

If you get a steady stream of hydraulic fluid, shut the nipple off and kill the engine. Check and top up your Hydraulic fluid reservoir and repeat the process once again.

If you did get a foam discharge, then one (or more) of your accumulators has ruptured and discharged its Nitrogen gas into your system.

After completing this exercise, clean around the nipples, start the car and make sure there is no leakage.

Kill the engine and carefully jack the car off the jack stands. Check your fluid levels in the reservoir and top up if necessary. Hope this solves the problem.

PLEASE BE SAFE AT ALL TIMES. THINK SAFE. WORK SAFE - you are more important than your car.

If there is no success from bleeding, Alternating the small solenoids should be your next step. If you do this and the other side sags you have narrowed your search to either (the specific) solenoid and/or its seals.
If after alteration the same side sags then it is either a current discharge to the solenoid or a leak in the system (for that side) * but this is highly unlikely.

Start with the simplest steps first and gradually narrow down your search to the specific area, this is the way to go.
 
crownhouse did an amazing job of cleaning and rebuilding the valve blocks on my CL55 this weekend. Highly recommend his work to anyone looking to have this done. Ensure that this is the problem with your system first however.

Thanks again mate.
 
ABC Hydraulic Valve Block Repair Rebuild

HYDRAULIC SUSPENSION RIDE HEIGHT DROP - SUCCESSFUL REPAIR
Member the88g contacted me by email, concerning both Front and Rear ride height drop on his Mercedes CL.
If the car was parked and left off, the suspension would drop in height on one side after about 30 minutes. . . Not good, so we immediately scheduled a repair, date and time.
Member the88g promptly showed up in his beautiful 2003 Jet Black CL 55 AMG with lush light Cream interior (jealous envy – mine is a simple CL500).
The job involved removal, rebuild and reinstallation of both Front and Rear Valve Blocks starting from the rear and finishing off with the front.
Total time taken was six (6) hours working flat out with only one 15 minute break.
After the rebuild, member the88g confirmed that the ride quality immediately became firmer, sportier, surefooted and more responsive.:thumb:
The next day after the car had now been left parked for several hours, member the88g got back to me and also confirmed that there was no drop in the ride height to the front and back suspension system.:thumb:
He also gave me a pat on the back with a few comments on this forum. THANKS:thumb:
The job entailed removal of both valve blocks, cleaning, checking their integrity, solenoid spring adjustment, replacement of all O-rings, rebuild, reinstallation, bleeding and testing.
With both Valve Blocks rebuilt, they should be good for well over five (5) years if the hydraulic system is maintained at working levels and kept clean.

I have advised member the88g to run the car for 200 miles, flush the old oil using (8-10 litres) Pentosin CHF11s with new filters (hydraulic and power steering – merc only), get two syringes of Xado EX120 Revitalizant for Hydraulic Equipment and add one and a quarter syringe of Xado EX120 Revitalant into the Hydraulic Stem reservoir and the reaming three quarters into the Power Steering reservoir.

The car should then be linked up to MB Star (C3 or C4) Diagnostics to have both a Preload and Ride-Height setting check/adjustment on all four suspensions.
:doh: I completely forgot to take pictures of the car but I managed a few pictures of the valve blocks. Hopefully member the88g will post pictures of his ride so we can all drool over with envy :D.

To keep the V8 in the CL500/Cl55 AMG or V12 in the CL600/Cl63 AMG working at its best, then with your next engine oil and filter change I suggest adding one complete can of Xado AMC Stage 1 engine oil revitalizant for SUV . . .
Atomic Metal Conditioner Maximum SUV with 1 Stage Revitalizant is a 3-component product of a new generation specially formulated for anti-wear engine treatment in SUV’s, Light Trucks, Buses with oil system capacity up to 10 qt. Due to Revitalizant the product reduces friction, rebuilds worn metal in engine parts and creates protective coating against future wear, thus providing tools-free restoration and anti-wear protection. Product application prolongs the life of your engine and allows avoiding expensive repairs in the future. One treatment lasts for 60,000 miles.

Valve block on car
8zel9x.jpg


Valve block off
2i0g1tu.jpg


Solenoid Retain
67kqyu.jpg


Solenoid Height
fupfso.jpg


Valve block stripped
2rfack9.jpg


Valve block rebuilt 1
xpbjgz.jpg


Valve block rebuilt 2
2vhwt8z.jpg


Xado EX120 for Hydraulic System
jud7hu.jpg


Xado AMC for Engine Oil
16b0fia.jpg
 
HYDRAULIC SUSPENSION RIDE HEIGHT DROP - SUCCESSFUL REPAIR
Member the88g contacted me by email, concerning both Front and Rear ride height drop on his Mercedes CL.
If the car was parked and left off, the suspension would drop in height on one side after about 30 minutes. . . Not good, so we immediately scheduled a repair, date and time.
Member the88g promptly showed up in his beautiful 2003 Jet Black CL 55 AMG with lush light Cream interior (jealous envy – mine is a simple CL500).
The job involved removal, rebuild and reinstallation of both Front and Rear Valve Blocks starting from the rear and finishing off with the front.
Total time taken was six (6) hours working flat out with only one 15 minute break.
After the rebuild, member the88g confirmed that the ride quality immediately became firmer, sportier, surefooted and more responsive.:thumb:
The next day after the car had now been left parked for several hours, member the88g got back to me and also confirmed that there was no drop in the ride height to the front and back suspension system.:thumb:
He also gave me a pat on the back with a few comments on this forum. THANKS:thumb:
The job entailed removal of both valve blocks, cleaning, checking their integrity, solenoid spring adjustment, replacement of all O-rings, rebuild, reinstallation, bleeding and testing.
With both Valve Blocks rebuilt, they should be good for well over five (5) years if the hydraulic system is maintained at working levels and kept clean.

I have advised member the88g to run the car for 200 miles, flush the old oil using (8-10 litres) Pentosin CHF11s with new filters (hydraulic and power steering – merc only), get two syringes of Xado EX120 Revitalizant for Hydraulic Equipment and add one and a quarter syringe of Xado EX120 Revitalant into the Hydraulic Stem reservoir and the reaming three quarters into the Power Steering reservoir.

The car should then be linked up to MB Star (C3 or C4) Diagnostics to have both a Preload and Ride-Height setting check/adjustment on all four suspensions.
:doh: I completely forgot to take pictures of the car but I managed a few pictures of the valve blocks. Hopefully member the88g will post pictures of his ride so we can all drool over with envy :D.

To keep the V8 in the CL500/Cl55 AMG or V12 in the CL600/Cl63 AMG working at its best, then with your next engine oil and filter change I suggest adding one complete can of Xado AMC Stage 1 engine oil revitalizant for SUV . . .
Atomic Metal Conditioner Maximum SUV with 1 Stage Revitalizant is a 3-component product of a new generation specially formulated for anti-wear engine treatment in SUV’s, Light Trucks, Buses with oil system capacity up to 10 qt. Due to Revitalizant the product reduces friction, rebuilds worn metal in engine parts and creates protective coating against future wear, thus providing tools-free restoration and anti-wear protection. Product application prolongs the life of your engine and allows avoiding expensive repairs in the future. One treatment lasts for 60,000 miles.

Valve block on car
8zel9x.jpg


Valve block off
2i0g1tu.jpg


Solenoid Retain
67kqyu.jpg


Solenoid Height
fupfso.jpg


Valve block stripped
2rfack9.jpg


Valve block rebuilt 1
xpbjgz.jpg


Valve block rebuilt 2
2vhwt8z.jpg


Xado EX120 for Hydraulic System
jud7hu.jpg


Xado AMC for Engine Oil
16b0fia.jpg


I have the same issue with my CL500. Is this something you could help me with?
 
Crownhouse you could make a killing from this and eventually buy your own CLS 55 AMG well done.
 
Many Thanks MAHA for your encouraging comment.
Currently these are my girls: a W215 cl500 (2003) and a W140 S320 (1993)
2cfrz4i.jpg
 
crownhouse,

I've searched high and low and no one will do a "Preload and Ride-Height" for me, indies either do not understand what I am asking for or have suggested going to a main dealer. I've also been informed to avoid Mercedes Benz of Guildford. I always had a bad feeling about them anyway.

What do you recommend?
 
crownhouse,

I've searched high and low and no one will do a "Preload and Ride-Height" for me, indies either do not understand what I am asking for or have suggested going to a main dealer. I've also been informed to avoid Mercedes Benz of Guildford. I always had a bad feeling about them anyway.

What do you recommend?

If you mean MB (The Sandown - Group Guilford Ex Tony Purslow ) then they are highly recommended on this Forum and a number of members use them.

If you need a recommended Indie give PCS a call 02392 570123 a Trader on this forum and a very pleasant drive down the A3.
 
Thanks for those recommendations.

My car is now booked in at Guildford.

Does anyone know if a rodeo is required as part of a Preload & ride height adjustment? I'd rather avoid it because of the unnecessary stress it can put on the system.
 
I'd have the rodeo done.. If it can't cope with it then you have an issue with the system.
 
Crownhouse that S320 is a lovley.
 

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