Overheating After Replacing Radiator Pump Thermostat Burp Coolant to Remove Air Pockets

Perfect, I just worked on the cooling system and now it's overheating.

So you're just working on your car truck, doing something in the cooling system, whether you're replacing a radiator, a water pump, or a thermostat and you added coolant and now you need to burp or bleed the system. When you're filling up your cooling system, the radiator may fill up to about 100% and then the engine may only fill up to about 80% and then there's 20% air, we need to get that air out. Because of the air pocket, it may not allow the coolant to circulate properly, the thermostat may not even open up allowing hot coolant from the engine to enter into the radiator and cooler coolant from the radiator to enter the engine cooling the engine down, which when the system is working properly, it'll keep the engine at an ideal temperature of 210 degrees. Some vehicles are pretty cut and dry. All you have to do is add the coolant, start them up, let them run for about 10 minutes, make sure the thermostat opens up, that's gonna burp any of the air out. And then you shut the vehicle off, let it cool down. Once it's cooled down, you top off the levels and you're good to go. But those are the easy ones. Some of them take a little more finesse.

In some vehicles, you may find that there's actually a radiator cap or a coolant cap attached to the radiator and those ones you can fill up the radiator pretty easily. Other vehicles have a separate expansion tank or a separate reservoir that has a cooling cap on that. Regardless of the system you have, some vehicles, it's just harder to fill the cooling system. You can just try to add the coolant right into the reservoir or into the radiator. Just make sure you have the correct 50/50 mix. After I'm done my repair, and I'm adding my coolant to the system and the coolant level is coming up, there's air on the top and it's pressurizing the air, it's got nowhere to go. For this vehicle as the air is coming up here and the coolant level is coming up, there's gonna be an air pocket right here and it's gonna come over to the radiator. And you could actually squeeze the hose a little bit and try to get some of the air pocket out. Now, this vehicle, it kinda self bleeds a little bit because there's a hose right here that goes from the radiator and that goes over into the reservoir. So there's not as much of a chance for an air pocket in this vehicle. Some vehicles will have a bleeder screw that helps out a lot, you can get a lot of the air out of the engine. This happens to be on the thermostat housing. So as you're filling the cooling system, you pop this open, you just loosen it up with a wrench. And as the coolant fills up, you're gonna hear air hissing out of that right there. And then as you see bubbles or you start seeing coolant come out of there, snug it up, and then you should be all set, there shouldn't be much air in the system at all.

But for some vehicles, this conventional method of adding the coolant isn't gonna work. You can always use a funnel system like this one where it actually attaches right where the coolant goes into the vehicle. And what helps with this is you can fill this completely up with coolant and run the engine with this on and it won't spill out the sides. That brings this level up that much higher so burping the cooling system works that much better. As the vehicle is running, you're gonna notice bubbles coming out of the coolant and that's normal, that's the air system burping and allowing more coolant to enter into the system. After you ran the vehicle with this funnel on here, the engine is hot, everything is burped out, let this cool down, let all the rest of the coolant go into the reservoir. And then once that's cool, you can take this little piece right here, put it in the funnel, then you can remove the funnel with the rest of the coolant. And then if you have too much coolant in there, you can use an extractor or a fluid transfer pump and just extract it so that you get the coolant level up to where it's supposed to be.

Another trick that works once in a while is raising the coolant fill as high as possible, whether you park the vehicle on a hill, or jack up the vehicle, or even use some car ramps. And then there's those extremely difficult vehicles to get the air pockets out, maybe even have an engine in the rear and the radiators are in the front and there's a whole bunch of areas where the air pockets can happen where they can hide around corners in different stuff like that. In those extreme cases, you can use a tool like this or maybe you even have to use a tool like this. This is an air lift system. Basically, when you put this on here, we're gonna put a vacuum on the entire system. There'll be a vacuum in the engine, vacuum in the radiator. So let's show you how this works now. You take the correct adapter for the vehicle, tighten it up, make sure it's airtight. Now we'll take this piece and we're gonna hook it up to compressed air, I'm just running this out of the way. It's gonna hook up right here. And hook up an airline and open this. That's gonna put a vacuum on the system, there is a gauge. Normally it takes a couple minutes to extract the system, and you can see the radiator hose is completely crushed down, which is normal. So there's a vacuum on the system. So with that valve closed, we can take this off, put this hose on. So now put this in the proper coolant jug. And we'll open this valve and see it's gonna suck all the coolant into the reservoir, and it's gonna go into the hoses. And it's gonna start filling up. And this makes it significantly easier to fill a difficult system. When you start seeing air in there, close it up, get another jug of coolant. Once the system is full, you can close this off, take the hose off, take this piece off. And then with that off, we're gonna run the vehicle for about 10 minutes monitoring the coolant level, just like you would a normal cooling system.

So let's start the vehicle. And we wanna turn the heat on low, you don't wanna have it on high. You want the blower motor pretty much as low as you can. And then let's change the mode. So the heat is coming out of here. You can turn the heat all the way up, but just keep the blower motor on low. So we want to monitor the temp gauge as the engine is running and just see where it is. And if it goes above that 210 degrees, then we want to shut the vehicle down. Or if you actually rev the engine a little bit, if you start getting up there, you can rev the engine around the 2000 RPM mark and it might help the system burp a little bit more. And if you notice that it starts coming down, then just let it run for a little bit longer. You should be good. If you notice the temperature going up, but then you still feel the vents and there's no hot air coming out of the vents, that's not necessarily good, there's probably still an air pocket and that's why you're unable to get heat out of the vents. If you get heat out of the vents, that's good.

The goal of running the engine for about 10 minutes is so the thermostat actually opens up and this acts like a valve and the coolant is gonna flow through. You can grab the upper radiator hose, just be extremely careful because when you grab this, if it's opened up and it's starting to circulate, this is gonna be so hot that you probably won't be able to hold on to it for too long. In some cases, you may notice the thermostat has a hole in it and that is normal. Now, when you're installing the thermostat, that hole should be at the top area so that more air can get through when adding coolant into it, and that's done on purpose. If you had installed it upside down, the air isn't gonna escape as easy and you could end up with an air pocket that's harder to get out. And also if you installed the thermostat backwards, which is possible on certain vehicles, then it's not gonna open and it's gonna cause your vehicle to overheat. So don't get fooled by that. Make sure you install it the correct way. So there's some tips for burping your engine or getting the air pockets out. If there's anything I missed, leave me a comment below. And if you enjoyed this video or it helped you out, make sure you subscribe to our channel, ring the bell, turn on all notifications so you don't miss any of our videos.