It's not the engines that have changed so much as the coolant itself. (To wit: Chrysler switched to HOAT coolant in 2001 on engine models that had been around for 15 years.) The newer HOAT formulations are simply better, just like multi-grade oil was an improvement over single grade oil. Do you use single-grade oil because that was the only thing available years ago?

In the original configuration, none.

Maybe I made a mistake by searching, reading, and them bumping an old post. All I really did was restart the same arguments I had spend hours reading and digesting.
From my readings, I concluded part of the issue was with the plastic components - not just the aluminum.

I'll just follow the recommendations I quoted in post #25. That made the most sense to me. Sorry for opening old battle wounds.

__________________
Charles
1983 300D, bought new, 215k+ miles, donated to Purple Hearts veterans charity but I have parts for sale: http://www.peachparts.com/shopforum/showthread.php?t=296386

Oft forgot in this conflaguration is that the Zerex G-05 has anticavitation properties. Most Green types do not. In our Diesel's Anticavitation can be achieved by additives in the Green or use of the G-05. Zerex claims it has Anti Cavitation properties. And so Mercedes uses it in Diesels since around 85, and backwards compatible they claim. I suspect the main advantage is there. Because we do know of Green dyed coolants that are low Silicate and would protect Aluminum and Plastic quite well. But they would have no anticavitation additives, normally, from the jug. Most of those SCA's to accomplish that part were added afterwards. And most Mercedes Diesel owners don't even realize that. Those of us with older Diesel Trucks are aware of it. And we still use Green Dyed low silicate antifreeze in ours but we monitor and adjust the SCA's on a regular basis. According to Zerex and Mercedes, the yellow eliminates that worry so I use it in the 300D. However I still am using Green with added SCA's in my 01 powerstroke. And, in my case, since I didn't know WHICH Green the PO had put in I changed mine.

Green is just a Dye. Zerex makes G-05 and could dye it Green if it wanted too. From what I understand they do indeed do so. For John Deere. They make it in a Green color for them.

__________________
1983 300D-Turbo - Deep Blue w Palomino MB Tex (total loss in fire 1/5/09 RIP)
1995 E320 W124 Polar White/Grey Mushroom MB Tex
2005 F150 Supercrew - Arizona Beige - Lear topper
1985 Piaggio Vespa T5 - Black and Chrome

www.cphilip.com

So bottom line, if I had a 50/50 mix of the green stuff in, and I drain it, but there are still a couple of quarts left in it, and then I add a gallon of G-05 with a gallon of water to maintain the 50/50 mix ratio, I should be OK?

__________________
1984 300 Coupe TurboDiesel
Silver blue paint over navy blue interior
2nd owner & 2nd engine in an otherwise
99% original unmolested car
~210k miles on the clock

1986 Ford F250 4x4 Supercab
Charcoal & blue two tone paint over burgundy interior
Banks turbo, DRW, ZF-5 & SMF conversion
152k on the clock - actual mileage unknown

They are compatible so I just add the good stuff as needed and have not had any problems for about a year now. I also drove my car for 3 years with just the green stuff with not issues.

__________________
1983 300SD
200000miles

Well, I drove mine for 5 months with the green stuff and had no coolant-related issues. No idea how long it had been in there though.

I just did an engine swap and then put a gallon of the G-05 and a gallon or so of H2O in with what coolant was left in it. Didn't do any kind of strenuous flush or anything to get the last of the old stuff out though. I figure there must've been about 2-3 quarts of it left in the various hoses, block, heater core, etc. - based on it only taking 2 gallons to completely fill it up....

__________________
1984 300 Coupe TurboDiesel
Silver blue paint over navy blue interior
2nd owner & 2nd engine in an otherwise
99% original unmolested car
~210k miles on the clock

1986 Ford F250 4x4 Supercab
Charcoal & blue two tone paint over burgundy interior
Banks turbo, DRW, ZF-5 & SMF conversion
152k on the clock - actual mileage unknown

I work with an excellent Russian engineer, and he told me when he was a student of 21 or so he and all his friends ran their cars on a mixture of Vodka and water in the cooling system. He said in Russia anti-freeze is scarce and expensive but every household has lots of Vodka around.

__________________
'81 300CD - 180K, cannot be killed by any conventional means
'99 Ford Escort - good MPG

I can just imagine how the car would smell if it had a coolant leak.
You would have every cop pulling you over to check for a DUI.

__________________
1983 300SD
200000miles

In that line if I had to drain the entire engine and/or system then I would put in the correct stuff but unless I had a problem I wouldn't bother. I have heard that it is a bigger issue with aluminum engines.

__________________
1983 300SD
200000miles

I suppose that it's a matter of whether one chooses to be proactive or reactive. Sort of like saying, "I'll start using sunscreen after I develop skin cancer."

Well i'm certainly glad that I ran across this old post. I'm in an interesting position. My 350 engine always had the green coolant but it ate it like no ones business and I was always adding water. However not once did it even come close to overheating always staying just above the 80' mark (the temp gauge only went up once on a summer day when I did my one and only speed run)


The 300 engine on the other hand (Which has the updated head) always gets hot in the summer, not overheating but definatly above the 2nd line. However thankfully i'm not worried about old coolant. We put new coolant in when we swapped the engine (Couple years ago) Two years ago the harmonic balancer was bad so the coolant was replaced at the same time. This year the key sheered because the dummy didn't do the job right so we did it ourselves and again replaced the coolant. So its been green for a while but at least its fresh green

Come spring time I think i'll be flushing and replaceing with this Zerex G-05 just to be safe.

__________________
1982 300GD Carmine Red (DB3535) Cabriolet Parting Out
1990 300SEL Smoke Silver (Parting out)
1991 350SDL Blackberry Metallic (481)

"The thing is Bob, its not that I'm lazy...its that I just don't care."

I started this all today with the bump. I do have an issue. I noticed in my reservoir tank a significant amount of sludge type material. Don't know what it is or why it's there but looks like a good flush is in order. I did a search for a good procedure and found the one I quoted in post #25.

Looks like a good thorough method.

Anyone got a better one or a good reason not to follow that one for a 617 turbo?

__________________
Charles
1983 300D, bought new, 215k+ miles, donated to Purple Hearts veterans charity but I have parts for sale: http://www.peachparts.com/shopforum/showthread.php?t=296386