After doing a coolant flush and change, I like to drive around with the heat on high to get circulation in the heater core. Fan is on the lowest speed to make driving tolerable, but is there any chance of damaging something? Like something in the dash or air ducts that would get too hot? It's only 50° more than when it's 40° out and you turn on the heat, so maybe not an issue?
Any harm in running the heater on high in this hot weather after a coolant change?
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I routinely run the heat in the summer to dry out the AC system. Have done this for 30 plus years with no issues.
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Isn't this what your supposed to do when you do a coolant change - to get any air bubbles out?
Also an old trick if your car is overheating - roll down the windows and turn the heater on high
Also an old trick if your car is overheating - roll down the windows and turn the heater on high
I was thinking a half hour or two.
On most modern cars, coolant flows through the heater core at all times, doesn't it?
The blend-air door has replaced the old system with the mechanical valve in the incoming heater hose.
The blend-air door has replaced the old system with the mechanical valve in the incoming heater hose.
But until the thermostat opens, the coolant doesn't flow everywhere.
I think the heater-coolant loop is on the engine block side if the thermostat, not the rad side.
Someone please jump in and correct me if I'm wrong.
Makes sense to me. I get heat before the temp gauge is anywhere close to where its sits when up to temp.
To help prevent hot spots coolant should always be flowing in the the block, if nothing else, getting all the engine up to temp, even before the thermostat opens.
No problem, Do it. I've done that 4 times to help cool my truck down once when it was overheating in crawl slow traffic in the summer where I couldn't just shut it off. Kept the temp gauge from going beyond 210. I'd just lower the windows and point the vents away from me because i don't want to cook any more than i have to.
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Your right at least some of the time - Nissan VQ's are that way. I can't say they all work this way however.
Where is the reservoir in that diagram? I just want the new coolant that I poured in the reservoir to mix throughout the system.
Won't hurt anything but why do that?just rev it @1500-2000 rpm untill it burps.
How will reving it or burping it make the new coolant in the reservoir mix throughout the system that has numerous hoses and passages.
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Its specific to a Nissan VQ - so whether yours is the same - don't know. However the Nissan VQ has the degas bottle feeding off a T on the heater core intake - which is actually purposely designed up and down so the up part of the hose is really high - presumably to capture any air in the system and send it to the degas (overflow) bottle. The bottom of the degas bottle is connected back to the top intake of the radiator - which in the case of the VQ, the rad cap on the rad itself is not a pressure relief type. The pressure cap is actually on the degas bottle. See my red arrow towards the degas bottle:
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What does your coolant resevoir look like? Does it have one hose high - and one hose low? If so, then the point is the coolant/air mixture flows in from the top, in which case any bubbles are extracted, and the system pulls coolant only back in from the bottom. In theory.
Not gonna with an overflow coolant reservoir.
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Coolant expands about 6% from cool to 200F. When it expands it needs to go somewhere. When the engine cools its shrinks back - meaning it needs to pull that from somewhere as well. Hence the tank - and the reason it has a hot and cold fill line.
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