mistertonyn

1/Do you guys run into a leaky petcock valve after closing it? Just asking because I want to be prepare...just in case...if it is a known problem.

2/I hear Xerex G05 is about half the price as the MB coolant...and it is the same formula. You guys are big fan of Xerex?

3/If I am just draining the radiator and refill....how many gallons of coolant I need to buy?

thanks.

RichardM98

Never heard anyone out here complain about a leaky petcock. Doesn't mean it couldn't happen.

If you change the coolant every three years as recommended, you can probably get away with just draining the radiator. System capacity is 10.6 qt. I believe I got about 8 qts out. You might pull a sample from the expansion tank. It should be clear,a light straw color and free of any suspended material. If there's any suspended material I would suggest a flush vs. a drain.

The amount you need depends on whether you are buying ethylene glycol (w/ additives) or 'coolant' which is a 50:50 (50%) mixture of ethylene glycol, additives and water. See container for which type. The MB stuff is glycol and needs to be diluted. So you need about 1g of glycol or 2 g of premix.

If you are diluting your own it's best (and cheap) to use distilled water unless you are sure your tap water is pretty low in mineral content.

Richard / E320

I'd add to get the pre-mix, or at least premix your ratio BEFORE refilling; seems like when you try to guess on the ratio, it's always off due to not enough of the old coolant drained out. With the premix, you don't have to second-guess...

Franasia

is fine. I replaced fluid in the summer and petcock valve seems very strong - I did not have any problems with it.

One gallon should suffice. What I did is get a good provision of distilled water (Reverse Osmosis is good also), and flush the system until you have only distilled water in it. Drive for a few miles and drain again, close the radiator drain and add the full container of Zerex without premixing and then top off with distilled water as needed. Leave reservoir cap off overnight for air bubbles to escape. Don't forget to put it back on the next day!

There's always water left in the system, so if you premix, mixture will be diluted. Hope this helps.

Cheers

Figuero

Franasia, your flushing/re-fill procedure will leave you well shy of the 50% mixture usually recommended as a minimum protection level. E320 has a 10.6 qt capacity and an E430 has 11.8qt.
This requries 5.3qt/5.9qt of antifreeze minimum. 4qt is only 38%/34%

ohlord

8.5 qts/10liters
5.5 liters of glycol take you down to 50 below 0

Figuero

10L = 10.6 Qt.

Figuero

US Qt that is.

Red66GT

I just had to replace the radiator in mine. So with removing the radiator and replacing it, I only needed to buy 2 gallon jugs of the Zerex. Picked up 2 gallons of distilled water at Y'allmart. I had a little of both left over and it was enough to fill the hoses, radiator, and fill reservoir. I did not do a full flush as I had that done a year ago. I did leave the fill cap off overnight too to let any bubbles vent....not sure if this helped or not, but my temp gauge rides at the exact same spot before radiator replacement.

Had no problems with the draincock.

mistertonyn

and will get you the 50/50 ratio. I am just going to open the petcock and let it drain as much as possible...no need to go further than that....getting to the drain bolt on the block is too much work and asking for possible leaks and other issues.
Anyone knows roughly how many gallons will come out from this (petcock drain only) method ?

Figuero

Since you're going to the trouble why not fill/flush with distilled water to get all the old antifreeze out. Then simply add the correct amount of antifreeze and top off with DW. Invest in a hydrometer to verify.

BTW 50:50 is considered a minimum blend for corrosion protection. If you live in cold climates why not boost it to 60:40 or even 65:35? Not advised if you cruise Las Vegas in mid summer though.

Red66GT

Based on my post, just under 4 gallons.

mistertonyn

Ok Thanks...just curious...did your radiator started leaking and where? at what mileage is your car? and what brand and cost?

Red66GT

Here is what happened.......

https://mbworld.org/forums/e-class-w...ssing-pic.html

https://mbworld.org/forums/e-class-w...-exploded.html

E_Class_Benz

Hello everyone,
I just joined the forum (my 1st post) and wanted to resurrect this old thread in hopes of getting the advise I am seeking.

I set out to flush and fill my '97 E420's antifreeze yesterday, and am questioning my efforts as the amount of fluid I filled the system with is considerably less than the capacity listed in the owners manual.

I drained the radiator until now more dripped out. Then I flushed water through the system for 5 mins (flowing from the hose). Then I filled the system from the reservoir until full (with 3to1 mix water/antifreeze), and ran the car for 15 mins, then drained that fluid. Finally I filled the system with the proper water/antifreeze mixture. The final fill only took about about 7-8 US QTS... I was expecting 16 QTS like listed in the manual.

What did I miss?

Thank you in advance.

kajtek1

Where did you find the 16 qt info?
When you will never be able to drain all the coolant, 7-8 qt sounds right.
I always flush with distillate water and on final fill, I put 1 gallon of MB coolant and top it off with DW.
That gives me slightly lower than 50% ratio, but my cars never see negative F

E_Class_Benz

Thanks for the reassurance. I drove it around for about 10-15 miles after the fact, with no temperature issues, and still on the max line, so I presume all is well.

I got the cooling system capacity from page 135 of my owners manual. See attached.

kajtek1

Looks like E420 might have higher capacity, but it seems strange that adding 2 cylinders increase cooling capacity by 50%.
I would double check it. On my 300 and 320 the capacity is +- 2 gallons that is why I was always doing that 1 gallon of coolant and rest of DW trick.