Low Coolant level @ 20k? Help..

[Ultramaroon]

Originally Posted by stevesnj

Deionized water is a purer version of distilled water with lower Ph levels and less minerals than distilled water. But i know I saw somewhere where Subaru says to use Deionized water in their blue 50/50 coolant.

And yes a bad cap would allow the water in the coolant to vaporize but there would also bee higher coolant temps because of a pressure reduction.

Originally Posted by humfrz

It's my understanding that distilled water, cannot contain any amount of inorganic minerals. Why? Because the minerals that contaminate water have a higher boiling point that water.

Pick it up @Ultramaroon ......


humfrz

Wow, first let me backpedal. After doing some actual reading, @stevesnj, I concede that DI and distilled water are not the same thing. That being said, I don't really care about the electrically neutral compounds that went along for the ride in the distillation process. ...yet. o.0

This has piqued my interest. I do wonder why Subaru specified DI water.

[humfrz]

Originally Posted by Ultramaroon

Wow, .............
This has piqued my interest. I do wonder why Subaru specified DI water.

Most likely because it's a cheaper process (as compared to distillation) to purify water ......


humfrz

[BRZnut]

I noticed the same thing at ~18K miles. I just got some Subaru blue and filled it to the top line. Have been fine since. (now at 18K). Suspect maybe evaporation or not fully bleed at the factory and there was some air I the system

[Seiryuu]

Hello all, just posting here as I didn't want to create a new thread. I noticed my coolant reservoir was just below "Low" after sitting overnight so I started doing research and reading up on multiple threads on this. Since this is "overflow", it should be alright; after some driving, the level goes up halfway between "high" and "low".


However, I noticed that the coolant hose has what looks to be signs of dried coolant. However, I don't see similar marks anywhere else inside the engine bay and it is relatively clean. So was the coolant slightly boiling over time to leave those residues? I do occasionally drive spiritedly, canyon runs and all. Finding out the cause aside, what would solve this "issue"? Would a high pressure radiator cap help?


Feedback appreciated. Thank you.

[sato]

Originally Posted by Ultramaroon

High pressure maintained by a properly sealed system allows the coolant to reach higher temperature without simmering/boiling in the hot spots. The temperature variation is not a function of pressure.

What does change when the cap has a pinhole leak is the temperature at which the coolant begins to simmer. Those little bubbles travel to the high points in the system, one of which is the leaky radiator cap so "bloop bloop," while you're driving the bubbles invisibly escape right through the coolant reservoir. Then, when the engine cools down, the remaining internal bubbles, which are pure water vapor, condense and the entire space is taken up by liquid from the reservoir.

The boiling rate is a function of the heat input and the flow rate of the leak.

I recently started experiencing coolant issues, but my car is 150k miles in. Some shop stated they saw "collapsed" coolant hoses. Although there has been a lot of Stop-Go traffic in my route (can't wait for Winter vacation), I'm not experiencing any coolant boiling over marks. Seems cheap, so I will start by checking/replacing for a leaky radiator cap to ensure it is not the cause of the problem.

I know this is not my topic, but might still be a good place to add my findings for people having issues OVER @20k miles.

[Ultramaroon]

It's as good a place as any. Collapsed hose is interesting. If you're not losing coolant, and a hose is really collapsing, I would guess that something is keeping the fluid from returning to the system as it cools. A clogged reservoir hose? Stuck return valve or whatever it's called? I'm talking about the little one in the middle of the cap. It should open really easily, and is usually the one that leaks in the first place.

[sato]

Originally Posted by Ultramaroon

It's as good a place as any. Collapsed hose is interesting. If you're not losing coolant, and a hose is really collapsing, I would guess that something is keeping the fluid from returning to the system as it cools. A clogged reservoir hose? Stuck return valve or whatever it's called? I'm talking about the little one in the middle of the cap. It should open really easily, and is usually the one that leaks in the first place.

I have yet to notice the collapse hose (mechanic didn't specify which one) but did observed the top coolant hose as not being completely full. On the other hand, the return valve spring seemed OK. Although I haven't inspected all hoses thoroughly, I did inspect coolant level (same as last night after refilling it until it cooled with cap open) and the original radiator cap, where I found one of the top (wider/bigger) seals was ripped in a few spots (refer to attached pics).

Ordered the radiator cap but bought a TVS unit/Autozone: new one doesn't go as deep as the original one into radiator. Nevertheless, I put it in.

PS Parts shop mentioned that our cars have two (2) thermostats or flow control valves, but I can only locate one. Apparently auto trans cars have two (2) thermostats.
https://www.oemgenuineparts.com/v-20...and-components

[Ultramaroon]

Look at that! I've never heard of such a thing. Now I wonder how a failure would present itself.

https://gt86stuff.onrender.com/t3Por...00RTE03TX.html


Opens at such a low temperature!

https://gt86stuff.onrender.com/t3Por...0335X02CX.html

1. INSPECT THERMOSTAT

(a) Immerse the thermostat in water and then gradually heat the water.

HINT:

Hold the thermostat with a wire or the like, so that the thermostat does not come into contact with the bottom of the container.

(b) Check the valve opening temperature of the thermostat.

Valve opening temperature:

48 to 52°C (118 to 126°F)

HINT:

If the valve opening temperature is not as specified, replace the thermostat.


(c) Check the valve lift.

Text in Illustration
*a

Valve Lift

Valve lift:

6.0 mm (0.236 in.) or more at 63°C (145°F)

HINT:

If the valve lift is not as specified, replace the thermostat.


(d) Check that the valve is fully closed when the water inlet with thermostat is at low temperatures (below 45°C (113°F)).

HINT:

If it is not fully closed, replace the thermostat.