green coolant???
 

Hi MB gurus -

Just a quick question. My father, trying to be a good samritan, took our `90 500SL into Sears (gasp) for a coolant change. They put the green crap in it. So, when I got the car back, I scheduled a coolant flush and change at my local MB dealership. The car happened to be coming up on its 45K service, so I had it all done at the same time. However, when I got the car back, it still looks like green crap in the reservoir! Does anyone know what color is the actual Mercedes coolant (which I understand is formulated for their aluminum radiators)? Any other easy way to tell if they actually changed it out? They signed my book and everything, but I'm still suspicious...

TIA,

just off of clear. Slight yellow tint.

yea, it's a slight amber colour. If the dreaded green is still in there it should be pretty obvious...

Sounds like they drained the radiator and block, but didn't remove and drain/clean your expansion tank.

Bottom line - they didn't do a complete job.

Take it back.

And a coolant "flush" implies just that!

If all that's done is drain the old coolant and refill with MB coolant, there is still residual residing in the engine...so the green is still there.

Mercedes Benz Antifreeze Yellow/Orange
http://img42.exs.cx/img42/5083/DSC02033.jpg

http://img43.exs.cx/img43/8067/DSC02055.jpg

Zerex G-05, which should be commonly available at auto parts stores is the same formulation as MB brand and is MB approved. (Read the label.)

If you have a commercial shop do the job, buy a suitable quantity of G-05 and distilled water to make a 50/50 blend and tell them to install it. The system should first be thoroughly drained (radiator AND block drains) then thoroughly flushed out with water before installing the G-05.

Duke

Thanks everyone! I'm taking it in Thursday to have them look at it. Makes me wonder what else they didn't do. I guess it's time to look for a good indie shop...

re: green Prestone permanent antifreeze
 

I have an old 450sl (1977) that I just replaced the "green" (quote "deadly" antifreeze) after 5 years! The green was clean and no signs of rust, dirt, etc visible. I think that a lot of mercedes owners have been brainwashed regarding "mercedes original antifreeze only safe to use!" I dont know what crap mercedes is building in the last few years, but suggest this is propaganda from meecedes. just my thoughts. Abe g

i aint afraid of no green goblin... just keep it alkaline.

Actually, I don't really care what brand it is as long as it's formulated to work with aluminum, but since it's the dealer, I expect them to use MB.

I don't like green (well, Prestone) because I've seen and known of quite a few aluminum radiators that got sludged by the green, not even rodding them out could save them. Of course, if it were a beefy three-row brass core rad like on my Land Cruiser, then I wouldn't care so much, but MB uses aluminum, so I want to make sure I'm using coolant that is chemically friendly to aluminum.

Thanks,

Conventional green antifreeze has a lot or inorganic salts that, over time, precipitate out and clog up the radiator tubes. GM Dexcool and Japanese OE antifreeze products have purely organic corrosion inhibitor packages that will not precipitate out salts that clog up the tubes, but there is some concern that Dexcool will not provide proper protection for solder joints such as traditional brass radiators and heater cores.

MB brand (same as Zerex G-05) is a "hybrid". Its inhibitor package consists of both organics and inorganics (including silicates), but the inorganic dose is much lower than green stuff and builds up deposits much more slowly while providing excellent corrosion protection for all cooling system materials - both modern and vintage. G-05 is OE fill for all DC and Ford light duty vehicles, and I believe it's also approved by many HD diesel engine mfgs. including Cat and Cummins.

Traditional green antifreeze is obsolete. It is no longer factory fill for ANY automotive OEM and is being phased out by most antifreeze manufacturers. The industry consensus appears to be that hybrids like Zerex G-05 are the best replacement for cars that traditionally used green stuff, and the proper blend organic should continue to be used for GM cars (Dexcool) that had it front the plant. Since the Japanese O)EMS don't like one chemical component in Dexcool, they have their own house inorganics, and it's best to use their house brands. (Honda does NOT LIKE the fact that GM is using Dexcool in an engine they provide for Saturn.)

The green stuff generally allowed at least 10 years service (with proper change intervals) before it started clogging tubes causing hot running or overheating, but at some point after that the problems begin - sooner if proper change intervals were not followed.

If you have green stuff, replace it with G-05 and your cooling system components will last longer before they need to be overhauled or replaced.

Duke

My dealer did same thing to me and gave me a free reflush.

green prestone antifreeze OK by me
 

I have read and heard about the effect on aluminum radiators by the green stuff. I am not a Prestone salesman! but heres my experience. I am the original owner of a 1963 split window stingray Corvette. (thats 41 years plus) I just changed my greenPrestone after 7 years (needed new water pump). drained radiator and backflow flushed(partial). This with an aluminum radiator with 90,000 miles! Still fine and still original thermostat. No clogged nothing! no overheating ever, I guess each case is different. Abe g

I'm also an original owner of a SWC. My Harrison 316 radiator was toast at 15 years with regular coolant changes at two year intervals. My Cosworth Vega needed a rod out at 10 years, and I had the radiator rebuilt three years ago. Like the SWC, it received bienniel coolant changes with green stuff.

I now use Zerex G-05.

Duke