StarTuned article on Mercedes antifreeze - MUST READ
 

This is the best article I've ever seen. It's a 'must read' for all Mercedes-Benz owners:

https://mbwholesaleparts.com/StarTuned/pdfs/AntiFreeDec04.pdf
(1.8MB PDF file)

This should probably be a 'sticky' on the forum, no??

:D

I say yes for a sticky!
And thanks for finding that study, Dave!

I can't take credit for finding it, please direct thanks to Aaron (speedy300Dturbo). Fabulous article though. It also highlights the need to replace your original coolant tank on the 1986/87 OM603 engines, as the old one has no silica pack, but the new tank has the silica pack. The tank is about $50 or so and is nice and white, instead of yucky yellow/brown:

http://www.meimann.com/images/merced...lant_tank1.jpg

OK, Thanks Aaron!
Dave, you really make me want to go out and remove my wretched looking OM603 tank, man!
OK, I'll do it but only after I finish a radiator and belts and H20 pump replacement on my wife's '83 300D (then I get the '87 back :) :) )
Reid

Excellent article! I'm glad I used the MB stuff and decided to spring for the new reservoir as well.... thanks Aaron and Dave! :)

Good artical! But where is the silica pack in the new tanks? When I got mine I didn't see anything inside.

So why not ues Evans waterless coolant and eliminate the problem with water in the cooling system all to gether?

In my opinion, its worth using Evans to eliminate the pressure in the cooling system alone.

P E H

How To flush??
 

I've got green in mine, As soon as the temps get warmer for a day, I'm gonna change it. I want to drain it, fill with plain water, drive for an hour, drain again, maybe use a Radiator flush product, flush with water again, then fill w/ MBZ coolant + distilled water.

any thoughts?

cheers,
RObert

Probibly a good time to do a Citric acid flush at this time too.

I plan on doing that with my recently acquired W12 300D as it also has the green stuff in it now.

The citric acid flush usually isn't needed unless you are having cooling issues, and/or know there are deposits built up. What I like to do is this:

1) With the engine COLD, drain the radiator AND engine block, then disconnect a heater hose or two and stick a garden hose into various hoses with the drains open. This gets probably 95% of the old stuff out.

2) Either close up the drains and fill with MB coolant, or use a flush to do extra cleaning (if needed). If you do this step, it becomes more time consuming to flush afterwards, as you either need to wait for the engine to cool before the garden hose treatment, or flush with hot water (not possible for some people).

3) The flush for citric acid is more critical and requires flushing, refilling, getting engine to operating temp for ~15 minutes, and repeating at least twice!! It takes practically all day (BT, DT).

4) When re-filling, DO NOT start the engine until you can feel liquid in the upper radiator hose, same as before you drained the system. Some people like to fill the block through the hose and then quickly connect it to the radiator. Some engines (like the M119) are horrible to 'burp', some require patience (OM603), some are relatively easy (OM617, I think) and some even have a handy bleed screw (M103).

Putting cold water (i.e. from the garden hose) into a warm engine is a formula for a cracked head or block, don't mess around with that.

I investigated the Evans before I did the coolant change on the SDL. It looks very attractive for all of the noted reasons. The reason that I didn't go for it was the fact that the heat transfer properties of the Evans coolant are only 74% (IIRC) of water. A 50-50 mix of antifreeze and water gets you to something like 90%. With the 603 a bit marginal on cooling in the summer, I felt it a bit of a risk to drop the heat transfer capability by this much.

Anybody do a 603 with the Evans coolant and have some real data?

I still think a citric acid flush is good pm at this time...........you can hedge off a marginal problem before you buy 2 gallons of the good stuff.

These cars are all old enough to have some crud build up and if its been neglected it might be far worse. After all do you know whats been done in the last 20+ years.....most of us don't have the records to show it.

I'm doing it as a source of due dilligence and preventive measure. Before I put the good anti-freeze in it.

Wray Stanley (IIRC) converted his OM603 to Evans a year or two ago. He's on the MBZ.org diesel list and has been quite happy with the results. I forget where he lives though, and ambient temps make a big difference with cooling on a W124 (pretty much any W124, diesel or gas.)

;)

Yes, the location is critical. I'd be fine with the Evans coolant if I could be sure that the ambient wouldn't go over 80°F.

But, sometimes it gets close to 100°F. :eek:

Brian,

I have Evans installed in my 603 engine but have little data since I haven't put many miles on the car.

In my 617 engine I am satisfied with the performance of the Evans for about 2 years. Yes the engine runs hotter up a long hill like in the Rocky Mountains than it would with conventional coolant but as soon as it gets over the top of the hill, it cools quickly. I have seen the temp gage up to 250*F for short periods of time with no boiling, coolant loss or pressure in the system. But I have seen it hotter with conventional coolant in extreme conditions. The red line on the temp gage is 260* and that is probably because that is the maximum temp of conventional coolant and not having it boil.

P E H