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it's about time I do a coolant flush on my 2012 E350 4matic, I noticed some guides mention the use of distilled water, while other's simply say drip it out and pour new concentrate mixed with distilled. It's been quite some time and my coolant is a dark color.
What's the best process to go about flushing/cleaning my coolant system?
If it helps it's the m276 engine and I'm sitting at 170k miles currently.
The safest and most foolproof approach is to flush with a proper coolant/water mixture as then you can be sure of the ratio of what's in the engine. It's tough to get every drop of the old coolant out doing a flush, so I would do this. Drain what's in there leaving the drain open. Remove the upper radiator hose and pour another gallon of coolant/water into the engine. This will flush out a fair bit of what's left in the block. Then, button it up and fill as usual. Drive it for a while, refill as the bubbles get worked out, and then check the coolant again. If it still looks off, do the flush again. Two full flushes like that should be plenty.
You'll definitely want to use distilled water. I would go to the dealer and buy the coolant there. Their price is good and you know you'll be using the right stuff. Then you can pour out half the jug into a clean bucket, fill it back up with the distilled water, and then pour the bucket into the distilled water jug. Presto, two gallons of properly diluted coolant!
The safest and most foolproof approach is to flush with a proper coolant/water mixture as then you can be sure of the ratio of what's in the engine. It's tough to get every drop of the old coolant out doing a flush, so I would do this. Drain what's in there leaving the drain open. Remove the upper radiator hose and pour another gallon of coolant/water into the engine. This will flush out a fair bit of what's left in the block. Then, button it up and fill as usual. Drive it for a while, refill as the bubbles get worked out, and then check the coolant again. If it still looks off, do the flush again. Two full flushes like that should be plenty.
You'll definitely want to use distilled water. I would go to the dealer and buy the coolant there. Their price is good and you know you'll be using the right stuff. Then you can pour out half the jug into a clean bucket, fill it back up with the distilled water, and then pour the bucket into the distilled water jug. Presto, two gallons of properly diluted coolant!
Good luck, let us know how it goes!
I have a quick question for future flushes. When draining the radiator hose, is there a funnel or pan that I could use to stop it from splashing everywhere and somewhat be able to contain it?
When I'm going to be making a liquid mess, I use my plastic cement mixing tub. They come in (at least) 2 sizes, 20X28 and 24X36, HD, Lowes, etc and for $7 - $17, they're very handy. We have even used these for the grandkids as bath tub because they don't like a shower.
@atraudes another question after the final flush I filled up the coolant reservoir with only about half of what my manual says to put in, more just wouldn't fill in. Will it lower as I drive around?
When I'm going to be making a liquid mess, I use my plastic cement mixing tub. They come in (at least) 2 sizes, 20X28 and 24X36, HD, Lowes, etc and for $7 - $17, they're very handy. We have even used these for the grandkids as bath tub because they don't like a shower.
That's a great idea, sadly I'm a tad big to use it for a bath tub. But nonetheless will pick one up sometime this week!
The tub is a good suggestion. The radiator should have a drain valve and outlet at the bottom, though, which greatly minimizes the mess.
As for refilling, yes, it'll drop as it heats up and circulates. There's lots of little cavities where air is trapped and as they get worked out they'll end up in the reservoir. I like to keep the coolant jug in the passenger seat for a while just in case. The first drive you make after filling should be around quiet neighborhoods where you can pull over quickly when you get the low coolant warning. Basically keep an eye on it and make sure it's topped up.