[Oni]

I am about to change the coolant in my evo x, I saw the mishimoto radiator install movie, it was simple, unplug under the radiator, and fill up at the cap.
I also read the service manual, that describes it more complicated, I need to remove the whole intake assembly, the compressor bracket, and the turbo charger water return hose.
My question is, must I do it the hard way, or the easy way? What are my risks if I don`t dissassemble intake and turbo water return, I always thought it simple like the oil change, unplug the bottom of the radiator and fill it up with the new mix.

 

[evo101]

If you open up the rad and call it done you're not doing anything. You'll get like 3 liters of the 7.5 in there. Unless you take it away for a power flush you won't be gettting all the coolant sitting in all the little engine crevices. You can also take the garden hose to the thermostat assy and flush it that way. The system works on vacuum and will piss for days if you open the turbo water line.

 

[Oni]

My car was bought 2011, and that means it was manufactured in 2009, first reached Europe 2010, and the coolant is at least 3 years old or more, the car has 27000 km on board, around 17000 miles, must I change coolant, or should I wat for it?

 

[Yxd68]

Yes, change it. It's kinda of a PITA without an easy way to drain the block so you need to keep pushing water through it until it's clear, then drain all you can reach.

Once it's 100% clean water, drain the radiator and as much of the head/block you can (taking off the thermostat housing helps but that's a LOT of work). then add 100% coolant to the radiator and mix it up (run engine for a minute). Then drain more radiator and add 100% again until the mixture reaches the desired ratio (use coolant tester).

The coolant machines won't do any better of a job as there's no easy way to flush/drain the block (that turbo drain hose is VERY difficult to get to).

We didn't buy EVOs because they were easy to service, right?

 

[AdhesiveTeflon]

Good to know...I haven't changed mine out yet since I got the car.

 

[Oni]

Me too, and I am afraid that I will mess this up, I have no clear idea of how to do it properly, and I don`t trust any mechanic with my car in my area, I usually print out the service manual, but this time that is not clear also.

 

[Oni]

Yes, change it. It's kinda of a PITA without an easy way to drain the block so you need to keep pushing water through it until it's clear, then drain all you can reach.

Once it's 100% clean water, drain the radiator and as much of the head/block you can (taking off the thermostat housing helps but that's a LOT of work). then add 100% coolant to the radiator and mix it up (run engine for a minute). Then drain more radiator and add 100% again until the mixture reaches the desired ratio (use coolant tester).

The coolant machines won't do any better of a job as there's no easy way to flush/drain the block (that turbo drain hose is VERY difficult to get to).

We didn't buy EVOs because they were easy to service, right?

I understand that you need to push water through the system to clean it, but where do you enter the water, and where will the exit be?
And do I use tap water to wash the cooling system or waste a lot of distilled water?
Another question is, I know I fill it with water and run the car with the heat on max until it warms up, and after that drain all the water, this also helps wash the system, but how to fully drain the system, so only the premixed cooling liquid is filled, I thought it will be done with compressed air?

 

[illariskustvo]

Yes, change it. It's kinda of a PITA without an easy way to drain the block so you need to keep pushing water through it until it's clear, then drain all you can reach.

Once it's 100% clean water, drain the radiator and as much of the head/block you can (taking off the thermostat housing helps but that's a LOT of work). then add 100% coolant to the radiator and mix it up (run engine for a minute). Then drain more radiator and add 100% again until the mixture reaches the desired ratio (use coolant tester).

The coolant machines won't do any better of a job as there's no easy way to flush/drain the block (that turbo drain hose is VERY difficult to get to).

We didn't buy EVOs because they were easy to service, right?

That ^

So far changed coolant twice. Definitely go with distilled water. Make sure you get all the bubbles out and turn up some heat at full blast.

 

[Yxd68]

And do I use tap water to wash the cooling system or waste a lot of distilled water?

Yep. I use tap water and change it every couple years anyway. But my tap water is probably much different that yours.

Another question is, I know I fill it with water and run the car with the heat on max until it warms up, and after that drain all the water, this also helps wash the system, but how to fully drain the system, so only the premixed cooling liquid is filled, I thought it will be done with compressed air?

See comment below about heat setting. Don't waste your time. The only reason to run the engine is to use the water pump to push the coolant around, thus evenly mixing what's in the head, block and radiator. Until you're ready to do hot system pressure testing (look for leaks).

Coolant system cleaning solutions help clean the system - hot water does not. Although hot water is a good rinse cycle. It's VERY important to get all the cleaning solution out before installing the semi-permanent coolant. And be sure to rinse several times.

For draining/rinsing I took off the ~1/2" heater hoses at the thermostat housing and connected the garden hose there. Filled until it flowed out the lower/upper radiator hoses, stopped and let it all drain. Repeat until perfectly clear. Then drain as much as possible (which does not drain the block).

There's a coolant hose going from the block to the turbo that would allow *some* draining of the block to occur but it's a real PITA to access. Looks like the support brace on the turbo inlet side has to come out and it's still a cramped space. Best to replace that hose also as it's probably old and brittle by now.

Using compressed air to push out the coolant would be very difficult at best. It's not like there's an access port at the top and a drain port at the bottom. You could probably blow out each tube and hose - if each end is freed - but that's not gonna work for the head/block/water pump/turbo unit as a plumbed assembly.

Make sure you get all the bubbles out and turn up some heat at full blast.

Heat setting does nothing to help here (although it *might* slow down the temp rise of the coolant). Coolant is already flowing full-time through the heater core - all the heat setting does is move the air flapper valve in the AC mixer box so more air flows through the heater core instead of around it. BTW - ALL air flows through the AC evaporator core no matter what the heat setting is.

BTW - I haven't seen a coolant flow control valve in an automotive application since the mid-70's.

BTW2 - Since many of these cars are 5+ years old, it's time to replace all those coolant hoses too. Plan to make a weekend of it. And get the proper set of clamp pliers - THAT alone makes this job so much easier.

I posted all the hose the part numbers previously, iirc.

 

[Oni]

The manual states that you need to remove the turbocharger water return hose, and inject water through the radiator cap and that means the water will exit the turbo water return hose, but after that if you just plug everything back you end up with a lot of water in the system, and my antifreeze is a 50/50 premix, how do I get the water out of the system and get the cooling liquid in?

 

[AdhesiveTeflon]

I kind of hope my X comes back totaled now so I can buy a new one and not do the 90k+coolant.

 

[Yxd68]

... my antifreeze is a 50/50 premix, how do I get the water out of the system and get the cooling liquid in?

Sorry, but you just can't get there from here.

Return the 50/50 blend (or use it on a different project) and get only 100% real coolant (2 gallons) and a coolant strength tester. Add 100% to the empty radiator space, run engine to let it mix with whatever is in the block. head, turbo, water pump, heater core, etc., then test the strength level. Drain the radiator and again add 100% coolant to the empty space in the radiator. Lather, rinse, repeat until it reaches the desired (50%) mixture ratio.

Iirc it takes at least two complete radiator drain and fills with 100% to get to a 50% mix.

Be sure to capture and properly dispose of all drained coolant. It's VERY toxic. Consuming antifreeze (aka coolant) will kill dogs, cats, birds, spiders, snakes, bats, small children, etc. And carefully wash your hands anytime you touch coolant.

"Dogs and cats find antifreeze quite tasty and if they find antifreeze they'll drink it. Antifreeze is extremely toxic causing kidney failure that is often fatal in just a few days. Very small amounts of antifreeze can be fatal. If a cat walks through a puddle of antifreeze and then licks its paws, it can ingest enough antifreeze to cause death. About five tablespoons can kill a medium sized dog."
http://www.vetmed.wsu.edu/ClientED/antifreeze.aspx

BTW - Do all your leak/pressure testing with 100% water. It's cheaper and much less mess to clean up afterwards.

 

[Oni]

Now this last reply cleared the issue. I need 100% antifreeze too.

 

[mistermarc]

I've always used 50/50 mix with no issues, why 100%??

 

[Koolzero]

I didn’t realize I was so late on the interval for this but the more things I read the more confused I am. I have a 2011 with about 45,000 miles.

I bought 3 gallons of distilled water and one jug of ZEREX and I already had part of a Mitsubishi brand jug of coolant left can I use these two different brands?

But then I see someone is saying use non premixed, what is the best 100% non premixed to use? Does Mitsubishi have one?

The Mitsubishi owners manual says: “Do not use water to adjust the concentration of coolant”. So again I’m really confused on what to do.

My original plan was to drain pour in distilled water to flush then fill up but now I’m seeing stuff about filling it up with full strength stuff until it dilutes itself. Any help to this would be really helpful.

 

[Koolzero]

I didn’t realize I was so late on the interval for this but the more things I read the more confused I am. I have a 2011 with about 45,000 miles.

I bought 3 gallons of distilled water and one jug of ZEREX and I already had part of a Mitsubishi brand jug of coolant left can I use these two different brands?

But then I see someone is saying use non premixed, what is the best 100% non premixed to use? Does Mitsubishi have one?

The Mitsubishi owners manual says: “Do not use water to adjust the concentration of coolant”. So again I’m really confused on what to do.

My original plan was to drain pour in distilled water to flush then fill up but now I’m seeing stuff about filling it up with full strength stuff until it dilutes itself. Any help to this would be really helpful.

I forgot I had posted this. I pretty much followed the steps outlined below that I saw posted on another forum. I will do another one this year to dilute it more. I bought authentic Mitsubishi coolant and returned the stuff I had bought from the O'Reilly's.

I used this coolant filling kit seen in the youtube video linked below showing an Evo getting "burped". I bought the kit from Amazon but recently learned that basically the same kit is at Harbor Freight. (134) How To Bleed or "Burp" Air Out Of Your Car's Cooling System To Prevent Overheating! DIY - YouTube another video I used for reference (134) How to do a Coolant Flush On An 09+ Ralliart - YouTube

1. Pull the radiator cap
2. Loosen the drain (don't remove all the way), let coolant drain
3. Attach radiator funnel / filling kit
5. Fill with distilled water
6. Drain water
7. Fill with coolant
8. With funnel still in the radiator, start car, look for coolant to bubble
9. Squeeze hoses to help "burp" the system when it stops bubbling, replace cap.
10. Remove coolant expansion tank and pour old coolant and clean out debris
11. Replace tank and Fill coolant to desired line

Afterwards I checked the coolant concentration and it tests good.

I just recently installed the MAP expansion tank and catch can, so this will probably slightly change the process, I'm not sure if I'm going to pull out the tank, because it's kind of a pain in the ass to fit in compared to the oem plastic one.