Is there a guide anywhere on flushing the coolant on the w210 turbo diesel? Everything I come across is usually for the E320 and surely it's different for the E300 due to the different engine.

I have the Schwaben tool for refilling coolant to make sure there are no air pockets so that's covered, I'd just prefer to do it right rather than just drain the radiator and refill and only do the job halfway.

Edit: I've searched and can't find a specific guide for this car, so I guess I'll have to do the traditional drain everything, refill with distilled water and run it for a while with heat on full blast, drain, rinse and repeat until it's clear. Then replace the thermostat and fill with the proper fluid.

No bugging. We are here to help.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

The flushing is very easy on the 606 engine, it has a radiator drain and a block drain (its at cylinder 6 and looks like a giant bleed nipple)

first drain coolant from both drains - it will remove close to 2 gallons of fluid in about 20 minutes, close them then ready up some citric acid solution and fill up the system (from top radiator hose first into the engine - this is mandatory).

Start it and let it run for 10 minutes then drive the car for another 10 or 15 minutes, allow engine to cool off and then drain and flush away with a hose while catching the effluent in a kiddie pool, to make this very easy, buy a generic heater hose and a radiator flush kit from the parts store, make up the kit on the new hose and disconnect one of the old heater hoses to install your "new" hose.

connect the garden hose to this, close the tank cap, open both drains and let it flow for another 10 minutes. - once done. let it drain, disconnect your made up heater hose tool and install your old hose, once drained as best as it can from both, fill er up with concentrated coolant from the top radiator hose into the engine, install hose to radiator then fill up the rest of the system with distilled water very slowly to prevent air lock in the top of the cyl head.

you will need 1 gallon of concentrate and 1 gallon of distilled water, You can choose to use G-05 or G-48 coolant or whatever Heavy Duty diesel spec coolant you please.

I personally find that filling and diluting a few times takes a lot of time and effort and causes a lot of waste which may lead to rain drains, This is why I personally like to drain everything and catch them for disposal, the water and acid mix is also caught into containers - the final rinse is mostly just plain water. The job is done in quick time and best efficiency.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

Everyone has their opinion on this issue; I've been fighting rust in the cooling system for a number of years. I'm going to purchase a good quality rust cleaner and flush the system then refill using Evans WATERLESS (no water = NO RUST) to the system.


Last time I flushed the system using the Mercedes citric flush six times straight and the prestone flush kit to back flush and there was STILL rust in the system!

I've never been able to eliminate rust in a cooling system once it takes hold.

One of these days I will try Evaporust or Rust911 and see if it will clear out the rust.

This is very odd, I have been able to remove severe level rust and also oil from a cooling system - all that you need is a systematic approach to how to tackle the flow and where to catch it.

I have cleaned out rusted systems that were run with straight water instead of coolant for years, the system was so packed with rusty sludge that it almost closed off half the radiator tubes, I have used oxalic acid to clean the rust too (its a GM approved procedure)

You need to find a way to make sure that liquid flow can get everywhere, otherwise the rusty sludge will be trapped in the lower sections.

e.g. I recently dealt with a GLK350 which had an ATF cooler failure - the system was packed with grease pretty bad, (killed the transmission too) - I looped the ATF cooler lines to an external cooler and proceeded to clean it.

its a U shaped cooling system if you look at it and the way I had to soap it out was to use the top little air bleed hose while closing off the upper radiator pipe to get the water pump to force out the greasy slurry which was done by adding cascade dishwash and then some citrus cleaner to the system and letting it run for an hour, then flushing it like I mentioned for about an hour in which I exchanged close to 20 gallons of water. Then waiting overnight and redoing the water flush with another 10 gallons of RO water, The result was a sparkly clean cooling system before I changed the radiator.

If you think cleaning these easy cooling systems is difficult, You wont want to tackle modern Nissan, Mazda, older GM etc.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

Ugh. Had the trans heat exchanger fail on my X5 and flushing it took a bit too. Caught it early before it killed the transmission thankfully.

I'm actually fixing up an overheating '90s Nissan Sentra right now lol! This was when we pulled the rad.



Had the radiator opened and cleaned, and took out the stat and did a token flush from top hose out the bottom before putting in the cleaned rad. Needed to check of it had head gasket issues, but it ran without overheating yesterday so looks good.

Still thinking if I will do a complete loop flush as it's a beater but its pretty much ready to run right now.

I always thought this was an interesting machine; some transmission shops use it.


https://hotflusher.com/

This machine is used for cleaning atf heat exchangers or even oil coolers, Any transmission shop which is not a swap and pray type will have it.

Its not going to help with rust in the cooling system

Interesting!

I'm of the school of thought where in a system that develops catastrophic failure, the coolers are replaced along with the rebuild/replacement. That would be neat for the other times though.

That unit is used to clean a good condition heat exchanger when a transmission is replaced. Its useless when you have a compromised exchanger.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

You must degrease the cooling system before you put the 10% citric acid solution in for that stage of a proper flush. Oil will inhibit the effectiveness of the acid.

Shout Gel is recommended by some folks here because it does the job without leaving you a weeks worth of flushing to get rid of the bubbles.

Flush the engine, radiator and heater coil with water then flush the engine alone with the block plug removed. Put the plug back in it, add the Shout Gel and fill with water. I really don't know how long to drive it because I did my flush with a sump pump in a 5 gal bucket and ran each stage of the flush 15-24 hours.

Flush the Shout out of the engine, radiation and heater coil then flush the block with the block plug removed.

Now it's time for the acid flush. I boiled 5 gals distilled water then added the citric acid by weight to 10%. That filled my entire cooling system and left plenty in the bucket so the sump wouldn't run dry. I imagine if I were going to drive my car I would have looked up the capacity of the cooling system and done some calculations.

Drain the acid including removing the block plug then flush the entire system and flush the engine again with the plug removed.

You'll be ready for football season when you get the coolant back in the system.

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84 300SD
85 380SE
83 528e
95 318ic

husky man wrote Last time I flushed the system using the Mercedes citric flush six times straight and the prestone flush kit to back flush and there was STILL rust in the system! .

This simply indicates you didn't flush it enough, been there & done that, it took me weeks if not a month to get all the crud out of my '82 240D's cooling system using the citric acid .

Also, what Clemson said ~ you really need to pre clean all the oil and rubber grease out first for the citric acid to be able to work .

Don't give up H/M., let us know how the waterless coolant works out .

It's been beastly hot here and I've been running the AC on max flat out during pedal to the metal road rallies, the car has never exceeded 100 degrees C and alays drops back to 82* C after a few minutes of idling or low speed street travel .

As long as you keep finding cloudy coolant you've not yet fully flushed it clean .

This drove me batshyte after a bit of solder bloom broke free and cut a hole in the water pump housing in Rhyolite, Nevada (google it, you DO NOT want to break down there!) - I fixed it but still had cloudy coolant, then I foolishly tried liquid TIDE ~ yes the oil came out easily, it also took me weeks and weeks of commuting and flushing at each end daily before the damned soap bubbles were gone....

This is just one more job YOU WILL DO BETTER AT HOME because you care and shouldn't be watching the clock .

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-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

When I had that transmission heat exchanger failure on my X5 that leaked ATF into my coolant, I did a lot of reading up on how to flush the oil sludge out of the system. Soap came up and was quickly dismissed because of the aforementioned reports of bubbles.

Dishwashing soap was mentioned as a less sudsy option but lots of reports of it being caustic to aluminum parts and I didnt feel like risking it.

I came across some Cummins cooling system cleaners that seemed promising. They have 2 kinds, one for rust and scale and the other for oil and fuel contamination. The specific products for specific problems aproach as opposed to an all-in-one sounded ideal and that is what I went with.

https://www.cumminsfiltration.com/south-pacific/cooling-system-cleaners

I used the Restore version and it worked well, no oil sludge traces left and no drama.

FWIW, I tested the most popular "degreaser" flush recommendations, including dishwasher detergent and laundry detergent and they didn't do squat against engine grease. But you know what did? Citric acid. I mean it really smashed through even the caked on stuff.

Turns out citric acid is well known as a fantastic degreaser according to the internets. So, me? I'd skip the detergent cycle. I feel like someone just decided once that it made sense and it became "common knowledge" without anyone ever questioning it, because of course soap cleans grease, right?

Just my two cents.