Overheating on the freeway, sticking thermostat?
yes it did, my temps are at least 8-10c cooler than it used to be on the freeway, most of the time if falls comfortably around 86-87c if I'm not hauling ***, though now I have another issue, that being the small amount of coolant slowly leaving my coolant overflow after every commute with zero indications of an external leak. Im gonna test for traces of oil in the coolant to see if I have a bad coolant seal, but I don't believe I do since I have zero symptoms. I checked the thermostat housing and it isn't leaking from there either, and i only removed that and the hose to swap the thermostat so I didn't mess with anything else.
When the car is running & coolant is hot, it expands; when you shut down, pressure & temp goes up, and that expansion needs someplace to go - so it gets routed to the overflow tank. Then as the system cools down, the system draws a bit of a vacuum, sucking the coolant from the overflow tank back into the engine. If you had some air pockets trapped after the coolant change, you'll notice the level of the overflow tank drop a bit on each drive until all the air pockets are burped out.
Ive looked up how you do the burp procedure, but I don't quite get it. I did warm up the car, put heat on max and squeezed the lines till no more bubbles came up, so not sure if I just need to drive it and the rest of the air pockets will flow out into the reservoir on their own, though I have a feeling that's not the case. regardless ill keep it topped up with coolant to make sure air doesn't get back into the system.
Here's a link on the 3rd gen section that has some pictures showing how it works (works the same way on FCs) https://www.rx7club.com/3rd-generati...ubbles-342309/
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From: Johnson City, TN
^What do you mean by that statement? The level of coolant in the overflow tank drops a bit below the FULL line after a drive/cool down cycle, or the overflow tank fills with coolant and pukes some out? If it's the former, that's pretty normal, especially if you just changed the coolant - you probably still have some air pockets in the system working their way out, and the overflow/coolant recovery tank is just doing its job.
When the car is running & coolant is hot, it expands; when you shut down, pressure & temp goes up, and that expansion needs someplace to go - so it gets routed to the overflow tank. Then as the system cools down, the system draws a bit of a vacuum, sucking the coolant from the overflow tank back into the engine. If you had some air pockets trapped after the coolant change, you'll notice the level of the overflow tank drop a bit on each drive until all the air pockets are burped out.
Easiest way to burp the system is to use one of these Lisle funnel kits when you fill the system. Here's an Amazon link, but you may find better deals locally: https://www.amazon.com/Lisle-24680-S...89109021&psc=1
Here's a link on the 3rd gen section that has some pictures showing how it works (works the same way on FCs) https://www.rx7club.com/3rd-generati...ubbles-342309/
When the car is running & coolant is hot, it expands; when you shut down, pressure & temp goes up, and that expansion needs someplace to go - so it gets routed to the overflow tank. Then as the system cools down, the system draws a bit of a vacuum, sucking the coolant from the overflow tank back into the engine. If you had some air pockets trapped after the coolant change, you'll notice the level of the overflow tank drop a bit on each drive until all the air pockets are burped out.
Easiest way to burp the system is to use one of these Lisle funnel kits when you fill the system. Here's an Amazon link, but you may find better deals locally: https://www.amazon.com/Lisle-24680-S...89109021&psc=1
Here's a link on the 3rd gen section that has some pictures showing how it works (works the same way on FCs) https://www.rx7club.com/3rd-generati...ubbles-342309/
That's normal then, you just have some air trapped in the system. A few more drives & heat cycles should fully burp the system; just keep topping off the radiator and the overflow bottle to the FULL line when it's fully cold. When it's fully burped, you'll see the overflow level will stay put and not drop below the line when the car cools down fully.
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Joined: Nov 2018
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From: Johnson City, TN
That's normal then, you just have some air trapped in the system. A few more drives & heat cycles should fully burp the system; just keep topping off the radiator and the overflow bottle to the FULL line when it's fully cold. When it's fully burped, you'll see the overflow level will stay put and not drop below the line when the car cools down fully.
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From: █▬█ █▄█ █▬█ █▄██▬█ █▄█ █▬█ █▄█
Try the Lisle funnel before you jump to any conclusions as stated above. If your coolant fill is lower than other components in your cooling system, its definitely a variable that needs to be ruled out.
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Joined: Nov 2018
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From: Johnson City, TN
by coolant fill, you mean where I poured the coolant in? if so, I pored the coolant through the cap on my thermostat cover, which is the highest point in the cooling system.
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