Aftermarket Subaru Blue Coolant Ok?
- Thread starter panthermike
- Start date
Great, to clarify, the first part of the procedure is ignition on, engine off?
Thank you for clarifying. He has a '19, so looks like it does have the TCV.
Does that vehicle have the TCV instead of t-stat? This TCV thing is new to me.
Yes it has to be engine off because you are flooring the accelerator
it tells you to start the engine in a later instruction.
unknown without a model year.
I’ll tell you from experience on the EJs it takes a long time, 20 minutes or longer in some cases. Try to have the front of the car on ramps or in the air to aid the bubble removal.
It’s a 2 people operation: one stands at the funnel and keeps it about half full (stand back far enough the burps don’t splash you), and the 2nd person holds the RPM on the engine at about 2000rpm. Vary a little higher and occasionally drop to idle, but you’ll get burps at 2k and above.
@panthermike please note that procedure still says to use the Subaru Coolant Conditioner.
Oh darn I thought they did away with the conditioner after 2010 MY or so?
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I used Zerex Asian Blue in my wife's Subaru Outback one year ago at 107k miles (120k miles now). No issues.
It’s right in there… guess not.
It gets confusing, in newer engines or engines that have the original HG replaced with MLS, Cometic/ Six Stars the conditioner (Holts stop leak) is not necessary. I guess Subaru needs to unload large stocks of this product.
Very helpful, thank you sir!
Did the job yesterday. Not too bad overall, pretty straightforward. I know some people have had difficulty getting it into coolant filling mode, but I was able to fine. You can hear the valve opening, although I'm not sure how much good it does. I did not use the conditioner, as it just didn't seem necessary. Also when my buddy picked up the parts, they recommended against it.
There was a ridiculous amount of air in the system that took about 15 to 20 minutes to resolve. After about 20 minutes and several short burst of raising the RPM, finally a really large amount of air released and The heat started blowing hot.
One other thing I thought was interesting is that in the past when I've done a coolant service, while draining the overflow tank drains as well. On this Forester, even after draining for 2 hours the reservoir was still at the full line.
He stayed overnight, checked this morning and reservoir was almost empty but radiator was full. Topped it off and sent him on his 150 mile journey home. I told him to monitor and check it every day or two for the next several days and top off as needed.
There was a ridiculous amount of air in the system that took about 15 to 20 minutes to resolve. After about 20 minutes and several short burst of raising the RPM, finally a really large amount of air released and The heat started blowing hot.
One other thing I thought was interesting is that in the past when I've done a coolant service, while draining the overflow tank drains as well. On this Forester, even after draining for 2 hours the reservoir was still at the full line.
He stayed overnight, checked this morning and reservoir was almost empty but radiator was full. Topped it off and sent him on his 150 mile journey home. I told him to monitor and check it every day or two for the next several days and top off as needed.
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That is a very long time to be running with large air pockets in the cooling system — it can cause damage to the head gasket.
For comparison, I performed some cooling system repairs to a FB25 last weekend — both thermostats and water pipe o-rings. I vacuum filled the system, filled the coolant funnel with a small amount of coolant and followed the factory procedure for bleeding. Started up, revved to 3K several times, shut down, topped off 4-8 oz. Repeated once more. On the third startup, level in the funnel remained stable and heater was blowing warm within minutes.
Helpful thank you, 15 to 20 minutes may have been an exaggeration but it was a decent amount of time. I don't think there's any damage, car is running beautifully at the moment. No temperature issues but will keep that in mind.
If you pop this hose off the throttle body when filling you will most of the air out, when you see coolant there put it back on.
That’s going to make such a mess. You’ll have to rinse the engine bay afterwards or else customer will be complaining about coolant odor for days.
Put a rag under it, you don't wait till it floods the place or put a piece of tubing over it into a bucket. It is mostly air when coolant appears its good. Vacuum filling is the best way.
Why is Zerex preferable to Peak?
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