How long to take coolant from reservoir into radiator?

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I just noticed the temp gauge on my Highlander nosing above the halfway mark. Looked in the coolant reservoir (not the inverter) and it was bone dry.

OK I will pour it in to near the full line.

Now how long will it take to go into the radiator? Does it get sucked in automatically when the radiator/engine cools down? Or is there some other factor here?

I'd like to take it for a spin to see if this is what was causing it to overheat, but I'd like to make sure it makes its way into the radiator. I suppose I can just check it every hour or two....
 
You need full coolant at the radiator neck, and no leaks. You may have plastic aero junk over the actual radiator cap.

The coolant will heat up, fill the hose, then start the siphon when it cools down and the pressure reverses into a vacuum.

Leaks would prevent the vacuum from forming.
 
Done it that way when I drained the radiator before, but it takes a while to burp the system, I was hoping I could just do it quick & easy into the reservoir.
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You should have some in the reservoir, but also fill the neck of the rad.

The coolant coming out of the cap might flash-boil in the hose due to the sudden lack of pressure. Having coolant in the overflow will condense the gas down and prevent its loss. It's better over-full than under-- the worst case is you'll burp a little out the top.
 
OK do keep in mind that this is for a hybrid--there is a separate reservoir for the inverter. Just to be clear.
 
Yeah I'm basing this off my 05 prius which could be a different shape with different high spots but has two "overflow" tanks.
 
Originally Posted by paulri
... Looked in the coolant reservoir (not the inverter) and it was bone dry.
OK I will pour it in to near the full line....
Is the reservoir the pressurized (newer) kind or unpressurized (as in older systems)?

If the level was normal a month (for example) ago, but is low now, you have a leak somewhere. Just hope it isn't the head gasket!
 
Right you were. It was the radiator. It was replaced and everything has been fine for a week now.

I asked if there was anything I could have done to extend its life and the mechanic said no. He said they're made of plastic and 15 years is what I could expect.

Originally Posted by The Critic
Radiator or Water Inlet plate. 90% sure your leak is from either one.
 
Yeah, it as a leak. Radiator was replaced and its worked fine for a week so that should be it.

Originally Posted by CR94

If the level was normal a month (for example) ago, but is low now, you have a leak somewhere. Just hope it isn't the head gasket!
 
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