This is kind of a shot in the dark but, I was wondering if anyone else has encountered this.

I noticed some oil spots in my driveway from my S600. There was also some oil in the garage which I didn't notice because the floor is painted. I checked the ABC reservoir and it's correct running and not running. (Not relevant here, but IIRC, you can tell if your ABC accumulators are good because the ABC dipstick will go to the upper mark when not running and drop to the lower mark when the accumulators are compressed with oil after starting.)

Anyway, the power steering Pentosin was a little-- a few ounces-- low, so I'm assuming that's the source of the leak. Here's something I found in a parts diagram:



#8 is the PS, but I'm not sure exactly where all the hoses run... With ABC, the V-12 has lines running everywhere. IIRC, the ABC and PS share a tandem pump but are isolated from each other.

So, I put the car on jack stands and removed the belly pans. I started the car and ran for almost 30 minutes, hoping to see the source of the leak. I got not one drop of fluid!!!



That's looking up at all the spaghetti running under the left front. Note how the accumulator is damp from oil, along with other lines, like the dripping must be coming from above.... Clearly, it's leaking but I can't see from where and can't get it to leak while up in the air.

So, I'm out of options and wondering if there's a common failure point on the PS system???

Anyone been here, done this?

Regards... Mark

 

I've been told that leaking tandem pumps is not uncommon. I've looked at prices. You can buy new, of course, and there are aftermarket rebuilds anywhere from $300-ish to over $700 or so. Honestly, given my experience with aftermarket and rebuilt parts for the Mercedes, if I decide to replace mine it's getting a factory part purchased from a dealer. Of the aftermarket parts I've bought, only the brake rotors and pads (not a lot to go wrong there) are still on the car. I had V12ICpack.com rebuild my coil packs, and they work great, but that experience was not without its frustrations and extra work either.

 

never worked on a ABC one - but fresh fluid and filter change every 2 years is essential - its normally in a mess at that timeframe, and the debris ends up ripping the seals to bits across the whole system

 

Thanks Guys:

Dale, today, I removed the air filter box, wheel and fender liner to get a better look. That didn't help very much but I was able to get eyes on the tandem pump and connections. Good thing or not, I'm pretty sure there is no pentosin coming from the pump.

I ran the engine again with wheels in the air after wiping down the damp spots. Could still see no leaks... So, I put the wheel back on and lowered the wheels on to 2 X 6's so I could still get under the car. Ran the engine, turned the steering wheel and raised and lowered the car with the dash switch.... Still no obvious leak; not even a drop accumulating.

I'm baffled??? I'll try putting a few miles with the undercarriage covers off and report back... It's raining out, so don't want to muck stuff up w/o covers.

Regards... Mark

 

Hi Mark,
I would try to wash the engine from underneath first. Especially the area where the leak is. Just use caution and cover any electric connectors down there. I have done it plenty of times when looking for a leak. That would make things easier and pinpoint the leak. As a matter of fact my friend just purchased a 2007 S550 last week that it is seeping pretty good on the front passenger side. So we washed it and now he is driving it without the belly covers. This weekend will go under again to spot the leak. Good luck!

 

is the whole system not under crazy pressure, I don't think you're going to see 1000 miles worth of weeping on idle after a quick wipe

 

Wait a tic... have you checked both the sides of the engine to make sure you're not just seeing a seeping valve cover gasket? THAT most certainly IS a known issue. You ought to be able to see enough of the ABC/PS pump to know if it's covered with oil or not. I had to replace my starboard valve cover gasket; the old one was hard and the side of the engine was soaked with oil. That can kill your coil packs as well, so it needs to be fixed if it's happening.

Another common source of leaks is the electrical connector on the front starboard side of the trans, but usually transmission oil is pretty easily identified by its color... unless it's REALLY bad off.

 

Thanks All:

It been raining here for three days so, I haven't had a chance to drive any distance.

Dale, it's not Mobil 1, I'm pretty sure. The spots in the driveway evaporated which leads me to believe it's pentosin. What's weird is, the source seems to be the cap on the PS reservoir... The oil has dampened the undercarriage covers from there down. No one has touched this car in over six years other than me so, I can't image the PS cap was loose. I can only hope it is that simple.

Interestingly, the owner's manual doesn't even tell you how to check the PS and ABC levels. Utube's give contradictory instructions... Engine running and Not... For the PS, engine must be off. ABC has different marks for running or not, in German.

BOTUS, point well taken about the high pressure, at least for the ABC. I replaced the ABC hose coming off the pump some time ago. No question about the source of that leak... Spewed 3000 psi pentosin everywhere. This one is only a seep. However, I had the inter fender cover off recently to replace a washer fluid pump and there was no seepage in sight.

Who knows? Since I have the belly pans off, I going to chance the oil and filter, when it gets here, at less than 4k miles. So, I may not report back for a while...

Many thanks... Mark

 

Just so y'all don't think I imagined this, the pic's in post #1 proves there was oil dripping and I'm sure as hell it was pentosin.

As mentioned, I wiped off the drips, ran the car on the ground and couldn't see any leaks. Well, it finally stopped raining here and, I made a 90 mile round trip with belly pan and left inner fender liner off. It's 93F outside and ran at triple digit speeds (kph, of course-- Ha).

Not a drip insight. WTF... Even most of the damp spots are gone. (I'm guessing pentosin will actual evaporate, especially in the Texas heat.)

So, I have two possible reasons:

1. I often don't drive the car for up to 3 weeks. So, maybe some seal got dry and started leaking???

2. The PS reservoir cap was loose??? I am almost absolutely sure the cap was tight when I first removed it after seeing drops in the driveway... However, I did remove and clean the gasket-- which slips off over the dipstick-- and could have corrected any PS cap sealing issue???

Occam's razor would suggest #1 is not likely-- in that a seal is not likely to re-seal, so to speak, itself-- and, #2, likewise unlikely, is probably the answer.

Good news is, the ABC and PS are okay. I don't even want to think about F'g with the ABC system-- done it once but that was replacing the easiest (main) hose to get to. Also, I'll add the gratuitous statement that, I love ABC... Well worth potential, costly failures...

Finally, and on possible issue #1 above, I consulted my MB, Jag expert from Manchester and, he suggested-- since the MB sits for long periods-- to use this:


I got it delivered from Walmart for under $20 today. I don't plan to use it, but I was willing to... nothing to lose if the leak persisted... except maybe the very expensive tandem pump...

Anyway... all's well that ends well... and, since I have the belly pans off, I'll prematurely change the oil and filter once the K&N PS-7033 filter gets here.... I've already had the 10 quarts of Mobil 1, 0W-40 delivered....

Regards... Mark

 

isn't the std engine stuff 10 30
did Mobil one ever move with the times, or is it still 15 year old oil that was great but now behind the budget stuff u get nowadays?

modern cars are oddly built to work with the exact spec manu stuff - I was watching video saying if you don't use 0 20 on the stuff that should they misfire - sounds silly but that video tutorial from amsoil

.

 

Not for the V12, no. In fact, not for any vehicle I own. The Toyota specifies 0W20, the Ford specifies 5W30. The Mercedes requires either 0W40 or 5W40.
Where on earth do you come up with this stuff?? You could email someone at Mobil, and ask them if they are continually researching and improving their product line, or if they're complete idiots and out of touch with their entire market. Hint: API and other specifications change over time, and manufacturers have to keep up.



M-B specification 223.2 shows what standard is applicable for specific vehicles. For the M275, that is specification 229.5, which tells you what is approved by Mercedes-Benz and meets their specs. 223.2 also says that the M275 (and several others) are limited to 0W40 and 5W40, further narrowing the selection.

 

the world of Oil is so different from when Mobile one came out everyone else moved on to signify the step change - maintaining an old name isn't helpful

and if you watch the first video the America slags of the USA API standard as obsolete - and mentions that ACEA categorisation is far better.... the car comes from an ACEA not API region

Muster 221.176
Class S
Model Saloon (2005-09 - 2013-06) V221
Sale designation S 600 (5.5L 380kW / M275)
Note Restriction: Only SAE 0W-40 und SAE 5W-40 engine oils are allowed! When using certain specifications/SAE grades reduced engine oil drain intervals have to be considered, see operating manual or service booklet of the vehicle.
Oil change quantity (with filter) 9 Ltr
MB-Approval 229.51

 

Thanks for the tutorials guys.

Dale, I don't remember where I came up with Mobil 1 0W-40. I know it was recommended in my 911 and had some laying around. I'm sure I verified it was correct for the V-12 but frankly, don't recall. Thanks for the confirmation. (BTW, for the V-12, 9.5 quarts is the exact measure for oil when draining from the oil pan drain plug-- which I prefer to the suction method. With no dipstick, it's hard to get an exact read on how much oil to add.)

BOTUS, here in the States, Mobil sells something they call "European Car Formula." I don't know if it's any different from plain ol' Mobil 1, but it is MB 229.3 and 229.5 approved.

Here's something else I found in the MB Maintenance Booklet:

Engine type MB sheet number
113 229.5
156 229.5*
272 229.5
273 229.5
275 229.5
642 229.51
*Restriction: Only SAE 0W-40 or 5W-40 engine oils may be used.

Just to be sure, I checked the MB guidance and it seems they aren't sure or changed their minds:



Their booklet says use whatever weight is correct for the climate. But their spec says:





I think Mobil 1 European Car Formula 0W-40 is the safest bet....

Since we're on an engine oil tangent, here's a short engine oil war story:

My XJ-8 had a coil pack fail when I was 300 miles from home. So, I drove it on 7 cylinders for an extended time. Everything was fine once I replaced the coil pack, but it soon developed a main seal leak; presumably from the prolonged vibration of the crankshaft.

The car had about 80K miles so, next oil change I used one the High-Mileage synthetics. I don't recall which one, but, the bottom-line is, it stopped the main seal leak and I've used the High-Mileage stuff in the Jag ever since with no drips.

But, back to the title subject and the PS? leak. I came up with a modified theory of why the leak might have come and gone: I've notice some dampness on the tie rod; very minor but presumably from the rack and pinion seal. That might explain why the PS was a little low. But, more importantly, if the reservoir was low, that could have resulted in aeriation/foaming of the Pentosin and it escaped out the cap, dripping down on all the crap below. Refilling the reservoir cured the problem.

I'll keep an eye on it and may use a little of the Pro-Seal referenced above to possibly stop the rack and pinion seepage.

Thoughts?

Regards... Mark

 

watching the first video gets in to the world of modern weird oils... with explanation of high or low saps....

it explains why modern oil goes wrong with age... the old high saps 800 stuff was great for screaming down an autobahn at 5000 rpm …. (saps short for sulphated ash, phosphorus and sulphur), but then those old world additives block the CAT or dpf. so in comes low saps that keeps the CAT happy but the engine now self destructs.... hence very expensive other additives to get the lubricity and endurance right and the CAT still happy.... but the new stuff ages and 3 years down the road doesn't give the level of lube u need even with only 1000 miles clocked up

 

I'd advise against it. Can't find the video on youtube but the guy is a popular transmission builder on there. He tore apart a transmission with Lucas Transmission Fix and it was amazing what it did to the seals/o-rings. Maybe can work if you only use it for a short period of time and then change all the fluid out.

Myself, I would go the UV dye route with a UV light. They have it for normal oil/transmission fluid, but I can't find anything in regards to pentosin. But the stuff is so benign I wouldn't have a problem using it.

 

Pro tip: Don't use it in coolant. It's not water soluble.

 

Thanks for the tips guys.

kn51, you gave me an idea that I hadn't thought of. I was going to syphon off the Pentosin and refill with new and add one once of the Pro-Seal (suggest use is 1 once per quart). Better idea is to add the Pro-Seal to the old fluid, run for a while and then remove the old and replace. Thanks...

For the time being, I think I'll just monitor the seepage at the rack and pinion and PS res level and see if it's actually leaking enough to be concerned. I think my biggest problem is lack of use. I just don't get to stretch her legs enough... For example, when I changed the engine oil, the old stuff looked pretty much just like the new stuff.... That's at < 4K miles...

Regards... Mark

 

Another contributor, with a different fluid leak, made me think of this...

Here's an update after about one year...

I used the one ounce of Pro Seal as described in the last post in the PS reservoir. About a week later, I suctioned out all the Pentosin and refilled.

No more leak and, last time I was under there, no dampness-seepage.

Regards... Mark