Unless there's a heater control valve within the heater hose line, your course of action is not needed. Coolant flows through the core at all times on many cars using blend doors for heat.
Any harm in running the heater on high in this hot weather after a coolant change?
- Thread starter atikovi
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Yet nobody seems to know how the coolant from the reservoir flows, hence my propensity to drive the car with full heat for a half hour or two to ensure it gets thoroughly mixed.
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2017 Corolla
do you still have a valve in the heater circuit? recent cars don't and use a mixer flap to direct air through the hot core or not. So you don't need to run heat as you run it always....
for the amount of cars you flip, i would advise to get a shop air powered vacuum filled system. Drain the coolant and pump all the air out of it with the tool, then fill lit under vacuum, no air bubbles no messing around. They are not expensive.
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Fleabay says this is the resevoir - is that correct? It appears to have a high and low hose barb? My guess is the low goes to the rad? Trace the high and you will figure out where the coolant comes from?
But again - the definite source will be the FSM - you can get a 48 hour pass from TIS for 20 bucks.
Simple answer is NO ....
I turn on the heat for a few minutes every time my truck sits for more than a week, Summer and Winter. Just to exchange and agitate the coolant sitting in the heater core. And for several minutes after a coolant drain and flush. The heater core is nothing more than a small radiator.
Does it help or not? I can only say that my truck is a 1991, and I'm still running the original heater core from the factory, that is now 32 years old. The radiator was changed once, 23 years ago.
Does it help or not? I can only say that my truck is a 1991, and I'm still running the original heater core from the factory, that is now 32 years old. The radiator was changed once, 23 years ago.
What makes you think I don't already have that? Filling it isn't the concern. It's mixing the new coolant I add to whatever water is left in the block and hoses that doesn't get drained out.
Nick1994
$100 site donor 2024
Just curious, why do you want to mix the coolant from the reservoir with the rest of the cooling system? It’ll do it eventually. Once the engine gets hot, it’ll overflow into the reservoir. When it cools down, it’ll suck it from the reservoir. But it won’t just flow.
You could drain the radiator a quart, suck a quart out of the overflow and pour it into the radiator to fill it back up, then pour what was in the radiator into the overflow to speed it up.
You could drain the radiator a quart, suck a quart out of the overflow and pour it into the radiator to fill it back up, then pour what was in the radiator into the overflow to speed it up.
So I can test the freeze point and adjust it if necessary and be done with it.
Once coolant (or whatever) makes it out the bottom hose of the reservoir, whoosh, it's very quickly mixing with the rest of what's in the engine and radiator. No worries. It probably goes into the 3/4" heater (radiator bypass) circuit which flows very quickly when the thermostat is closed.
I assume you know your capacity, added half coolant, and are topping off with water.
I assume you know your capacity, added half coolant, and are topping off with water.
I did, 6 quarts, so I added 3 quarts of concentrate and the rest water, but see it's only good to -12°F. Now I have to drain a little and add more coolant, drive it around until it's all mixed to check it again.
Most cars have a coolant control valve in the heating system. The ones in bimmers are open unless the valve is getting 12VDC.
Is this true? That that you have a heater core radiating heat out under your dash even in summer when the a/c is on?
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not to the car, but to you should you decide you want to hang out.
Well, I do have the windows open.
That's what I was thinking. It's pretty much an outdated and irrelevant thing on modern vehicles.
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