Subaru Outback Forums banner

1 - 11 of 11 Posts

·
Registered
Joined
·
25 Posts
Discussion Starter #1
Well, I finally bit the bullet and found an OB, checked it over and bought it last night!

Now, to get the coolant flushed and have her checked over more closely by a Subaru garage. Any suggestions?? What is involved in a Coolant Flush? Is it a DIY Drain and Fill or do they power flush the system and everything??
 

·
Registered
Joined
·
25 Posts
Discussion Starter #2
I''ll have some pics to upload soon, don't be mean, she has acne (hail damage) and a bit self concious about it...
 

·
Registered
2012 Outback 2.5 Limited
Joined
·
963 Posts
Given that the factory fill coolant is this prediluted, 11-year/132k-miles-before-first-replacement, special de-ionized elixir, I doubt there's a particular need to actually perform a flush unless there are specific concerns or issues (such as previous owner not using the correct coolant).

I personally just do drain-and-fills every now and then using the OE Subaru blue super coolant. Simple and easy to perform. Does it get the entire system flushed? Nope. But if you do it with some regularity that won't be an issue.

Likely I'm overdoing the maintenance by doing this, and sticking to the actual recommended schedule would serve me just as well. I just can't help myself :)

Now, if you still end up doing a flush there are a couple of things to consider:
- Unlike systems where undiluted coolant is available, you can't easily get to a proper 50/50 mix after a flush of this system, as water residing in the system after the flush (for example in the heater core or engine block) will dilute the already prediluted coolant when you add it. You could theoretically counter this by buying the concentrated blue coolant "additive" that is meant to be added for severe cool climates.
- Unless you actually flush with de-ionized water you'll introduce undesirable residue in the system from the water you use to flush, reducing the longevity of the mixture.
 

·
Registered
Joined
·
25 Posts
Discussion Starter #4
Thanks Dad ;-)

When I flushed my Ranger (and others) I would just use distilled water for the final 'rinse' and then add the required amount of concentrated Antifreeze, but you can't with the pre-diluted stuff! I don't think there is any issue but I just bought it with 122K on it but the previous owner took very good care of it and its all documented. I figure, I'll have it in for a full inspection, so have them do a Coolant flush, and I'll be good for another 100K miles...

I'm in central MN and wondering if it is worth it to goto Min/St paul to a dealer there, it isn't far. I want a good inspection of it as I have no lift and don't wanna crawl around under it LOL
 

·
Registered
2012 Outback 2.5 Limited
Joined
·
963 Posts
As others have pointed out in a recent thread technically de-ionized water is purer than distilled water so even flushing with distilled water won't be the same. I don't know the practical consequence. But - as stated my vote is for drain and fill, not flush.

Now, I've done coolant flushes on my old Corolla, using distilled water and getting back to 50/50 with concentrated coolant (Toyota Red). But I'd argue with these newer systems the best bet is just regular drain and fills.
 

·
On the Super Mod Squad
2002 Pair: 3.0 VDC Wag & 2.5 Limited Sedan
Joined
·
26,195 Posts
see the link in my signature next to the "?"


you can type out the specs on the car you got, year, engine.

as not all are created equal,...and you don't have to do it again,...until you buy a 2nd or 3rd subaru.
 

·
Registered
'13 Touring 2.5i CVT, ice silver
Joined
·
246 Posts
Guys,

I don't know about using deionized (DI) water in an automotive coolant system. I'm no expert but I have worked in an industry that uses copious amounts of DI water for a couple of decades now and it' s a known fact that DI will attack some metal surfaces, especially in the presence of heat. I did a quick online search and found the following interesting links:
Deionized Water - Application Note - Lytron Inc
The Hendrix Group > Resources > Technical FAQ > Corrosion > 316SS and Deionized Water Corrosion

Personally, I would stick with the factory pre-mixed coolant for any car I own.

Cheers
 

·
Registered
2014 Outback Limited 2.5im 2012 Impreza Limited
Joined
·
74 Posts
Thanks Dad ;-)

I don't think there is any issue but I just bought it with 122K on it but the previous owner took very good care of it and its all documented. I figure, I'll have it in for a full inspection, so have them do a Coolant flush, and I'll be good for another 100K miles...
I'm curious about you only considering the coolant at this mileage. Do your records show that everything else has been done to this point per the schedule in your owner's manual? L
In addition to regular engine oil changes, air filters, etc., lots of pretty important items should have been done by this mileage. Brake flushes, power steering fluid change, front and rear differential fluids, and maybe even a CVT service. If your Outback is a 2012 or earlier, it should have had, or be close to, a timing belt change. Maybe even some suspension components, like bushings, could have wear.
 

·
Registered
2012 Outback 2.5 Limited
Joined
·
963 Posts
Guys,

I don't know about using deionized (DI) water in an automotive coolant system. I'm no expert but I have worked in an industry that uses copious amounts of DI water for a couple of decades now and it' s a known fact that DI will attack some metal surfaces, especially in the presence of heat. I did a quick online search and found the following interesting links:
Deionized Water - Application Note - Lytron Inc
The Hendrix Group > Resources > Technical FAQ > Corrosion > 316SS and Deionized Water Corrosion

Personally, I would stick with the factory pre-mixed coolant for any car I own.

Cheers
Just to be clear though no one is suggesting running purely deionized water in the cooling system. What we're suggesting is that the water portion of the pre-mix coolant is deionized water. Left alone I don't doubt it's corrosive. Mixed with the right set of anticorrosive chemicals in a premixed coolant is a totally different story.
 

·
Registered
Joined
·
25 Posts
Discussion Starter #11
Super Dave;

The Diffs were flushed and filled along with the trany, all the recalls were done, regular oil/filter changes and even the plugs done at just over 60K... The brakes, coolant system, and PS, No Idea and that's why I was looking for a decent places to take it for a full inspection and some of the more difficult services. I can flush the brake lines and drain and fill the cooling system (If thats the best way) and vacuum out the PS fluid and change it once or twice. I just don't want to mess it up and have it cost me an arm and a leg down the line to save a buck.

Thanks!
 
1 - 11 of 11 Posts
Top