Just prior to purchasing my ’81 300 SD at the end of July, the previous owner had the radiator changed out- GOOD .

When the new one was installed, the green coolant (ethylene glycol) was put in- BAD .

I learned from this forums DIY links and Russell at Diesel Giant (a nice guy with very helpful “How to” pages and good customer service when ordering parts) that I should use the “Tea colored Zerex.”

What is likely to happen if I just leave everything alone, letting the fresh green stuff stay in?

The lower radiator hoses look old, so I’ll probably change them out real soon. I can use the correct coolant at that time, but how diligent do I need to be in trying to flush out all of the present green stuff? It seems that some report a lot of difficulty in even finding the block drain plug, nevermind removing it.

I'm thinking of just replacing the stuff I lose with more of the green stuff? How bad is this? Right now, I'm trying to keep things easy and quick, while trying to keep up with what needs to be done.

Please excuse my ignorance and thank you in advance. BTW, if there are any good shops or even shade tree mechanics in the Vero Beach area that are interested in making some money on the repairs that I feel are beyond me, please contact me.

I had the green stuff in my 30 year old 240D all these years, no problem. That said I am giong to change it to the latest MB coolant this fall for the first time, meaning that I need to really wash the system clean of the green before adding the good stuff.
It is my understanding that the green stuff does not hurt all cast iron engines, but you should not put that stuff in later models with light alloy heads etc.

Vahe
240D 77

vahe,
O.K., Let me show even more ignorance: Mine being an '81, is it one of the "Late Models" that the green stuff should not be used in, or is it an early enough model,like yours, that I shouldn't worry about it?

I know the valve cover is aluminum, but I don't know what, if anything, that would indicate.

The engine you have is all cast iron. There is some concern about the green stuff attacking the plastic in the radiator over time, but, nobody has proved it.

I wouldn't make a special effort to remove it. Just use the Xerex G-05 when you change it in two years........you will change it in two years, right??

I just went through this myself - my mechanic refilled the radiator on my 91 350SD with the green stuff and I asked the same question about whether it would ultimately be bad for the car or not. Being a good bit ignorant myelf, I also might be wrong, but I came to the following conclusion from the information I gathered from members of this site...

It seems the green stuff might be fine, but if you intend for your vehicle to be in service for 300-500k miles, the green stuff will corrode some of the cooling system components. In a typical production auto that is never really expected to last more than 100k miles, the green stuff is fine because the rest of the car will never outlast the cooling system.

Anyhow, just to be safe I bought MB coolant and had my mechanic flush out the green stuff and replace it.

"Let me show even more ignorance:"

Let me surprise you with even more ignorance, I have a new motor in my 240D, the previous motor which lasted 300K under stop & go city driving was serviced with conventional motor oil, non diesel rated, I did not know the difference, and the stupid mechanic did not either. Same goes for the green stuff, I am learning all this right here, hope that it will make a difference.

Vahe
240D 77

Thank you guys for your replys and clearing this up for me.

When I started searching for my first MB a few months ago, it was only with the thought in mind to use it as a commuting vehicle on the 10 days a month or so that I work at my fire department. 75 miles round trip on I-95. A relatively short and easy drive, but I wanted to keep miles off of my F-350 and I wanted to burn a WVO blend like I do in the truck. The truck sucks down the fuel too quickly and the MB allowed me to have a back up vehicle in case the truck developed any type of problem.

My original search criteria for the car was only that it be a diesel that ran well and had working A/C. I didn't care about rust, interior condition, etc. The paradox is that now that I have this car, I love driving it. I found a car in good enough condition, that has better curb appeal than I had hoped for. I look for reasons to use it instead of my truck or wife's Suburban. I am finding that this car I intended to be a "beater", that I went into with the mind set of cutting corners anywhere I could to get a return on my investment, has me wanting to make everything right on it.

I know that I do not have the talent or money to do a true restoration on it as I would like. At the same time, I am constantly wanting to fix little things and using restraint to keep from spending money on things I would like to fix on the car, but don't make sense given the car's purpose to be a money saver.

At the same time, I see other cars for sale on this forum and elsewhere and dream of having a MB in perfect conditon. Trading up. But, this would once again defeat my purpose of having the car.

What to do?

Yes, Brian, I promise to change out the coolant in 2 years and will do it with the right stuff at that time.
Thanks for your help.

fire,

Use Evans waterless coolant and U won't have to change it ever. Its the water that does the corrosion so with no water.............................

U can also leave the radiator cap loose so with no pressure in the cooling system all the components will last longer.

P E H

P.E. H.,
Sounds good, but I know it's pretty pricey up front and I've read that it causes the engine to run at a hotter temp.

I imagine a real thorough system flush is needed before the Evan's is put in. What about the water left in the system after the flush? How does that effect the Evan's?