Coolant Flush went wrong ?

[bunty660]

Hi All,
my 92 500e with 134K miles went thru a minor service ( coolant and trans flush) at yorks motorwerke in Walnut creek CA today.
Drove the car 50 so miles and checked the coolant and its thick like a green smoothie ( attached is a pic ).

Prior to the service I regularly peeked in the coolant tank and it looked normal then ( no sign of contamination )
and I was careful enough not to get the engine temp above the ideal state.

Things I looked right away for :-
Engine oil is clean ( dipstick )
Under valve cover looks normal no sign of sludge here..
Transmission Oil is clean ( had the trans oil change as well at the shop with pentsoin atf )
Car runs great no smoke on start up or running.

Going to request the shop to assess the situation.
But i wanted the experts to point me if theres is anything we may be missing.

Attached is a picture ( i took some sample from the tank )

 

[emerydc8]

I've never heard of the following happen to a W124, but maybe someone here can rule out this possibility, especially if the radiator was replaced with a Valeo.

I noticed the coolant in my 1999 S320 was like a milk shake. It turned out that the factory Valeo radiator was defective -- a known defect that Mercedes apparently hoped would show up after the warranty elapsed (like the W124 engine wiring harness). The transmission fluid was slowly leaking into the coolant system via an internal leak in the radiator. Eventually the coolant made its way into the transmission too. Not knowing what was happening, I flushed the cooling system about five times and every time the thick, light brown fluid would reappear in the expansion tank after driving it for a while. Anyway, the end result was to have the dealer replace the transmission, water pump, thermostat and hoses, after the transmission totally failed. I was sure to install a Behr radiator instead of Valeo. Naperville wanted $536 for the Valeo radiator, so Mercedes must really be proud of it. I wonder if they ever fixed the defect.

Did you ask the shop what coolant they used and the % dilution? Also, maybe they didn't fill the heads through the upper radiator hose and the air in the system is causing foaming. If the system was completely drained, I don't think it's possible to get coolant into the heads if you only fill the expansion tank (maybe someone else can comment on this). I always fill the heads first through the upper radiator hose, then put the rest in the expansion tank. Of course, once you run the engine and the thermostat opens the coolant goes in, but at that point, sometimes the results are problematic. But maybe this could cause the foaming that you're seeing.

 

[JC220]

I would ask what antifreeze they used. Could be an incompatability issue, in particular if they didnt drain the block and mixed a newer antifreeze into the system.

 

[gsxr]

Few random thoughts:

1) Green? The only approved antifreeze is yellow (G-05) or blue (G-48). If it's neon green coolant, ask what they used, as it may be the wrong stuff. There's also a faint possibility that the old & new coolant didn't mix well, if different types.

2) Ask if they poured in pre-mixed 50/50 or not. The factory manual has a typo that indicates system capacity of ~16 quarts. Actual system capacity is ~12 quarts. If they drained, poured in 2 gallons of antifreeze, and topped off with water... the system will have an excessively high percentage of antifreeze, reducing cooling ability / thermal transfer. The right way to do it is only pour in (or, vacuum in) pre-mixed coolant.

3) Use a turkey baster or other suction tool to withdraw some coolant from the reservoir. Is it ALL thick? Or just a layer of crud on the top surface of the liquid in the tank? I'm guessing the latter.

4) Ask if they FLUSHED the cooling system (which costs a lot more), or only DRAINED AND REFILLED (which is the typical service, much cheaper). Hopefully either way, they opened the 2 block drains, otherwise you only get ~5 quarts of liquid out.

5) Shops often have vacuum refill tools which eliminate the need to pour into the upper radiator hose, and if the coolant temp didn't go above normal, and the level in the reservoir didn't drop substantially, the amount of liquid in the system is probably correct.

6) AFAIK, there was never a Valeo radiator offered for the W124. Only Behr, Mahle/Behr, and Nissens. If you have ATF in the coolant, or engine oil, it will float on top around the edges.

 

[bunty660]

Great points,



Previously the car had the yellow ( i like to believe g-05) antifreeze before the service.
and i was told they replaced it with pink .( should have checked here ).

Going to verify the radiator brand and ask the shop to flush the system like I requested

 

[gsxr]

Definitely ask about the specific antifreeze used. AFAIK there is no "pink" juice approved by Mercedes, the current stuff is G48 (blue), which should be compatible with the previous yellow/gold G05. Details in PDF below:

http://www.w124performance.com/docs/mb/other/antifreeze_TSB_2012_G-48.pdf

Note that if yellow & blue are mixed, it may have a green-ish color, although not as "neon green" as the old-school Prestone stuff.

 

[nocfn]

I agree on the greenish stuff. I have drained some of the radiator in the past and topped off with 50/50 G05. When I removed the upper hose from the radiator the other day to install the new shroud, it was rather green (not prestone) in the color. Making me think that the mix gave me the green tint. I bought new drain plugs just in case and plan to drain block radiator and just start from my "known" quantity when I do my scheduled MX over next 6 mo.

 

[kwontumspeed]

I experienced sludge in a 4runner I used to own when it came back from a "flush". I didn't drive it long and took it back and they redid it (aka the right way this time) and no sludge afterwards. I think you got hoodwinked my a lazy mech.

 

[nocfn]

On the C126 M117, the "flush" is citric acid powder from MB. Is that the same for the M119 (easier to ask than look it up)

 

[gsxr]

Note that a dealer/indy coolant "flush" generally only includes draining, running clean water through the system to "flush" out old coolant, and re-filling.

Citric acid treatments, or de-oiling, are more complicated and more expensive. This is USUALLY not needed unless dealing with a specific problem.

 

[emerydc8]

6) AFAIK, there was never a Valeo radiator offered for the W124. Only Behr, Mahle/Behr, and Nissens. If you have ATF in the coolant, or engine oil, it will float on top around the edges.

Somehow, I ended up with a Valeo in my 1999 W140. Maybe it was replaced at some point with the defective Valeo.

How to tell if i have bad Valeo Radiator?

www.benzworld.org

 

[bunty660]

updates -

shop agreed to do a proper flush this time.
I supplied them with zero g-05 9 12 quarts - 18$ a gallon from o reily

the car has a Behr radiator ( unknown replacement date )

 

[emerydc8]

Bunty660,
Good to hear they will reflush. Did they tell you why it might have foamed like that? Make sure they pull both block drain plugs when they do it.

Note that a dealer/indy coolant "flush" generally only includes draining, running clean water through the system to "flush" out old coolant, and re-filling.

BTW, the dealer charged me six hours of labor to flush my radiator. I s#!t you not. The transmission was already out of the car and I was out of town when they broke the news to me. Talk about feeling raped.

 

[JC220]

Bunty660,
Good to hear they will reflush. Did they tell you why it might have foamed like that? Make sure they pull both block drain plugs when they do it.



BTW, the dealer charged me six hours of labor to flush my radiator. I s#!t you not. The transmission was already out of the car and I was out of town when they broke the news to me. Talk about feeling raped.

Yep the stealership got you good

 

[gsxr]

Somehow, I ended up with a Valeo in my 1999 W140. Maybe it was replaced at some point with the defective Valeo.

How to tell if i have bad Valeo Radiator?

www.benzworld.org

Jon, I think the Valeo radiator was a W140 thing (possibly other chassis too). But AFAIK they don't make one for the 124 chassis. I would have lost it with the service manager over the labor they charged you though.

shop agreed to do a proper flush this time.
I supplied them with zero g-05 9 12 quarts - 18$ a gallon from o reily

bunty, there is Zerex G-05 in both full-strength undiluted formula, and also a 50/50 pre-mixed "ready to use" formula.

If you bought 100% undiluted, make sure they only use 2 of those 3 gallons.

If you bought 50/50 premix, they may use most of it. Only about 11 quarts can be drained from the radiator & block.

 

[bunty660]

Thanks Dave

Update

Just got the car from the shop, I supplied them with 3 gallons( 11.5 qrts ) 50/50 mix and they returned 1/2 of it to me.
that means still not proper flush like i requested ! ( also pointed them before leaving to flush out from the blocks )

coolant condition is still the same ( very disappointing )
engine was warm to check the coolant state at the shop so waited untill now to see inside.

I have decided to do this myself as much as i hate dealing with antifreeze.
Also one imp to ask here .. Should i replace the radiator as well - i saw the leaktest date on it and its from 2006.

 

[emerydc8]

coolant condition is still the same ( very disappointing )

I'm not sure what you mean by this. Is it still foaming? What did the shop say about this?

If you want to rule out any possibility of a leaking head gasket, there is a fairly inexpensive kit you can get for this. Leaking Head Gasket Tester | Tools and Shop Equipment

If the car isn't having any cooling problems, you might just leave the radiator alone, unless you want peace of mind in knowing that it's new. For the price of a Nissens or Behr radiator, I'd probably replace it if I didn't know how old it was. If it was more than five years old, I'd probably replace it anyway.

You won't get a lot of coolant from the block drain plugs. If I recall it was around a quart; so I would be surprised if the remaining amount of whatever was in there before would be causing your foaming issues when mixed with new G-05

If you're going to replace the radiator, order the copper washers (4) that sandwich the banjo bolts for the transmission cooling lines at the top and bottom passenger side of the radiator. Like GVZ mentioned in another post, in a pinch, you can re-use the old washers.

When adding new coolant, I add a gallon into the top hose where it attaches to the radiator to make sure the heads are filled. Hold the hose up and pour it in, then put water into that hose too until it starts to overflow. Install that hose to the radiator and then fill the expansion reservoir to the fill level. That way there should be no air pockets in the heads. I like running a 30% dilution here in Tucson because it seems to be more effective at cooling and we don't have to worry about freezing temps; so I am only using a gallon of the 100% G-05 in my whole system.

I'm still puzzled about the foaming and what the shop thinks is causing this.

 

[bunty660]

Here are some latest pictures attached - coolant / atf / engine oil and internal.


i went ahead and ordered new behr radiator and head gasket tester.
going to do this myself.

I dont trust the shop anymore with the car although they did offer another flush.

Side note - ( never let the car overheat in my ownership -during hot days I switched on the heater, if i ever saw the needle above the operating temp )

 

[Jlaa]

Here are some latest pictures attached - coolant / atf / engine oil and internal.


i went ahead and ordered new behr radiator and head gasket tester.
going to do this myself.

I dont trust the shop anymore with the car although they did offer another flush.

Side note - ( never let the car overheat in my ownership -during hot days I switched on the heater, if i ever saw the needle above the operating temp )

Well at least you have metal oiler tubes, as opposed to the plastic ones. Score!

 

[gsxr]

Engine / camshafts / etc look mint.

ATF dipstick... is the fluid bright red? Not that it's related to your issue.

Coolant, if I'm seeing that photo correctly, doesn't look right. Seems as if there is oil in there, which is not good. If so you may need to go through the de-oil process which is a RPITA (just very time consuming). And, you may want to replace the plastic tank afterwards as it's difficult to de-oil the inside of the tank.

However, the bigger question is if you DO have oil in the coolant, how is it getting into the cooling system? De-oiling and flushing won't help if more oil enters when you're done.

Oh, also, where did you order the Behr radiator from?

 

[gerryvz]

One common place on W124s where coolant gets contaminated is in the windshield washer coolant heater control valve, which is at the bottom of the reservoir. This valve controls the flow of coolant through the reservoir to heat it up in cold weather, and is prone to leaking (or letting windshield washer fluid into the coolant).

 

[bunty660]

Dave - trans service was done at the shop as well with mann filter and pentosin atf , Radiator was ordered from autohauzaz.

Gerry - forgot to mention that the shop reconnected the coolant lines into the windshield washer tank at the time of coolant service !
Previous owner has bypassed it back ( assuming - Warm CA weather didn't require washer tank heating ). this could be a culprit too.

 

[gerryvz]

Your coolant doesn't look like it is contaminated with oil, to me. It looks like there is something else in it. I would have left it bypassed, indeed, given your climate.

 

[gsxr]

Cool, I was wondering if you got the Mahle/Behr unit from AHAZ. When it arrives, could you please check for decals indicating COO? Behr used to only be made in South Africa but I've been wondering if that has changed recently, given the low price.

I think you'll need to figure out what the contamination is in the coolant reservoir. Maybe try using a clean paper towel to extract some of the stuff in there. The images in post #18 sure look like engine oil to me.

Note that the washer thermostat failure generally causes a coolant loss, pushing cooling into the washer reservoir.

 

[emerydc8]

Here are some latest pictures attached - coolant / atf / engine oil and internal.

It's hard to see the coolant in your pic. Can you take a white paper towel or napkin and scoop out some of the coolant in the top of the expansion tank so we can see? Does it look like there's any oil floating at the surface?

 

[bunty660]

Jon - Definitely floating i just checked - underneath the gunk is cleaner antifreeze.
Also mentioning again - Antifreeze didn't have any floating gunk prior to the service performed ( not that they did something intentional )

attached are some additional pictures

 

[JC220]

Just makes me wonder did something happen In the shop... like they started it without coolant or low on coolant, got distracted and let it run too long

 

[gsxr]

Wild speculation: The goopy stuff ALMOST looks like a stop-leak product; which can remain in the cooling system for a long time. Usually it doesn't float up top though. Oil tends to float.

Your plastic reservoir looks very good on the outside, which is a plus. If there was significant engine oil in the coolant, there would generally be a dark line around the inside of the tank.

Is there any really good local shop you can have take a look at this mystery stuff? It's tough to identify via interwebs.

 

[gerryvz]

looks like oil to me -- definitely per latest phptos.

 

[bunty660]

first i am going check with the head gasket tester i just ordered ( thanks to Jon ) & then Hoping the new radiator with a complete flush ( taking Gerry's excellent DIY write up) will resolve hoping it was ATF getting in coolant.

post that well see, I want to believe its not head gasket at 130K miles plus it passed smog last year with low no#s and car has torque & never smokes, plus no contaminations in fluids other than coolant..

 

[emerydc8]

Wild speculation: The goopy stuff ALMOST looks like a stop-leak product; which can remain in the cooling system for a long time. Usually it doesn't float up top though. Oil tends to float.

That's exactly what I thought mine was. It was mostly floating on top of the coolant reservoir. When I bought the car, I regrettably didn't get a PPI. The engine was too hot to open the coolant reservoir cap when I bought it, so I didn't see it until later. I had heard about weak head gaskets with the M104, so I figured the prior owner added a head gasket sealer which seemed to be working because everything was running fine. I never would have suspected transmission fluid.

Anyway, here's the mixture of transmission fluid and coolant coming out of my radiator at the tail end of draining it. It was like chocolate milk.

JC220 said, "Just makes me wonder did something happen In the shop... like they started it without coolant or low on coolant, got distracted and let it run too long."

I hate to consider the shop was that incompetent, but I guess it's possible.

 

[pablo2696]

Cool, I was wondering if you got the Mahle/Behr unit from AHAZ. When it arrives, could you please check for decals indicating COO? Behr used to only be made in South Africa but I've been wondering if that has changed recently, given the low price.

I think you'll need to figure out what the contamination is in the coolant reservoir. Maybe try using a clean paper towel to extract some of the stuff in there. The images in post #18 sure look like engine oil to me.

Note that the washer thermostat failure generally causes a coolant loss, pushing cooling into the washer reservoir.

@bunty660 whenever you get the radiator please let us know if it has the decals that @gsxr mentioned. I´m about to buy a radiator and if that Mahle/Behr unit is made in SA, then it is a great deal

 

[bunty660]

Update -

Headgasket leak test came out negative

Warmed up the car and tested and tried to suck in any gases but the fluid didnt change color.
did it again after 15mins and gave the engine some revs to see still no color change.
at the end as the coolant level rose - accidentally sucked in the gunk + coolant inside the tester - still no color change ( not intended to so )

And please note the radiator got delivered today and its made in my home country India .
I dont knw if that will let down few folks hehe...


going to change the radiator and also noticed external oil leaks nr oil filter housing which should be next..

 

[gsxr]

Thanks for the info! Looks like they've been making them in India for almost 3 years now?!! Wow.

Oh, and btw... oil leak around the oil filter housing (against the block) is very, very likely coming from higher up. Probably cam solenoids. BT, DT...

 

[bunty660]

Final Update - resolved after 3 flushes, new radiator and a used reservoir, there is no more any oil or goo in the coolant ( 200 miles report )

here is what I did :-
0) conducted HG leak test with liquid tool - came out negative
1) replaced radiator
2) replaced reservoir with good used temporarily.
3) flushed out coolant with tap water then distilled water and then refilled system with G05.
4) took it next day to a "decent" shop to have them clean the system thoroughly using a cleaner and air evacuation tool to bleed it right.
5) Got car back with job well done ( but just incase added dye to engine oil to find if we are really done here )
6 ) Ordered new reservoir and some hoses to seal the system good.

Car was running great before this mishap but i feel much better now seeing the reservoir with clear fluid.