How to bleed coolant?

Hello, did you drain the entire system or just partially? These vehicles have a lot of smaller coolant hoses running all over the place, the best method is to Vacuum fill the system, it works really well. Along with checking for any leaks while under a vacuum for 2min or so. I know you work on a lot of vehicles, so it's worth the investment to buy one of these vacuum setups, they actually doesn't cost much, it pulls all the air out, and refills the system in about 5 mins, and you're done. Really great.

Ya thought about it, I just don't know what to buy. I have a kit that installs with a cap that tightens on top of the coolant expansion tank which tests for pressure. I doubt this is the vacuum one you are talking about.

There are instructions here for a system that was only partially drained and I'll post those so you can try that method as well.

For a partially filled system service info wants you to fill it until it comes out the bleeder port. Here is the steps for that section, I will post a picture of the vacuum bleeder system, it uses shop air hook up, and a hose that goes into the coolant so when you're done with the vacuum hold for 2 minutes as a leak test, it will draw the coolant right into the system using the vacuum its already under. When you use it once you'll never go back to filling it any other way.

But it almost sounds like there might be combustion gases pushing the coolant out, have you run a head gasket test on this thing?

This is the harbor freight version, I've actually used this one too and it works really well, I was surprised coming from HF.
I've had vehicles with head gasket issues that never over heated but would shoot the coolant out of the radiator like a volcano. But with a lot of air pockets stuck in various places, using the vacuum method is really the best and it's what service info recommends as well.

It does not smoke or overheat. We replaced the coolant flange pipe under the intake as it was leaking. Before that I did the thermostat. Bottom radiator hose doesn't get very hot. I did get some heat from vents for 3-4 seconds once. Now it's just 2 out of 10 as far as the heat is getting. The coolant boils with bubbles and no sign of a head gasket. I will run one once i get the vacuum pump.

Refresh this page, I added to my last posting.

So, the lower radiator hose is still cold. I used the tool I bought to bleed it and got a bit of heat. But the temperature needle stays in the middle but the scanner showing it to go above 230F. fan kicks on and goes high. So am thinking maybe the thermostat is defective, which is the one I bought from Amazon. Is it possible to remove just the thermostat from the assembly to see if water will circulate? or does the whole assembly need to be changed and it's part of it? Rear pipes get hot as far as heater pipes. Top radiator hose is hot but it's not very hard indicating anything.

I would avoid Amazon parts in all situations, almost all of them are knock-offs. Use rockauto com for parts, they have different brands and some OEMs as well, but thermostat spec is (Begins to open at 190-194f and is fully open at 216f) I will post a diagram of thermostat housing. Does this vehicle have a supercharger (turbo) of any kind?

Heres the thermostat and the cooling system for a non turbo.

You should check that you have good flow through the radiator, maybe just try running water through it alone, and make sure there's no build in it, but you're probably correct on the thermostat, it's not a part you want failing or not functioning correctly.

Even with the thermostat off the hose on top of the thermostat housing gets hot, the bottom one stays cold and temperature via scanner shows to go above 225, so i turned it off. Next thing is removing the bottom radiator hose and run the water through it. I found a few pieces of plastic came out the corkscrew left over from the coolant flange that broke earlier which we had to remove the pieces with a spoon. But I am hoping this isn't a head gasket. Pressure not holding cause there is a small hose which goes into the throttle body that broke so we just plugged it for now.

This is the hose so when i was putting pressure in the system i saw a few drops and heard a noise from it, so we removed it and plugged it for now. So, i can't even do a pressure test until i get a new hose.

Temperature needle on gauge stays in middle but via scanner goes more than it should.

Try doing the chemical head gasket test, its cheap enough, and that will give you an idea of if its combustion gases causing the issues or something else. If you have a borescope where you can look into the cylinders with the plugs out, you can check for coolant getting into the cylinders while pressure testing. So thats another way to check, I would do both of those tests, I look into cylinders all the time for various reasons, I like to visually see whats happening if possible.

Hmm, what is the chemical test? I can probably do the plugs test even though some of these cars are pain to remive all the plugs but its doable.

This is the chemical test, you should be able to get it at any AutoZone, Advance Auto, etc. Basically, the liquid will change colors if combustion gases are coming out of the radiator or cooling system opening. It's pretty cheap too. We used to use a gas analyzer to check for hydrocarbons and such at the radiator opening, but not many shops have them anymore.

But will this help me determine head gasket issue or just leaks in the cooling system?

But i need to fix the small hose first before i do that too.

Yes, it will determine a head gasket issue, with a head gasket fault the cylinder pressures push combustion gases into the cooling system and that's what the purple liquid will react with and change color.
For just leaking coolant hoses or components, I like to do a pressure test first, only up to whatever the max psi on the radiator cap is, usually 15-18psi range. Then after a repair I will pull the cooling system into a vacuum and let it sit at 25-30 inHg for 3-5 minutes to make sure it will hold under that vacuum. I do both testing methods because certain leaks can happen when under positive pressure and not under a vacuum and the opposite as well, but yeah, you'll want to replace any hoses first.

Do you have one of the temperature probes to see if the ECT sensor is accurate? To compare it to scan data.

What do you mean temperature probe? Car gets to middle needle on gauge quickly but i read online that these cars do that's how they are. But the fact that fan comes on high, and scanner shows it to go up and water boiling in reservoir tells me something is up. It's possible that there are gases in the reservoir and water isn't boiling. Not sure. But none of the hoses is super hard or anything and the lower hose is always cold. Not sure if any is related to the leak that was there under the intake. Car starts first time. No smoke at all. And no rough idle.

But what if you do a pressure test and it fails but it's not due to a head gasket but rather to a leak somewhere that is small and you don't see it?

Well, if it's full of coolant and you pressurize the system with the coolant leak kit you will see coolant coming out somewhere, that's the reason for putting it under pressure without the engine running. To simulate running conditions. If you have bubbles coming up at the reservoir, use the head gasket chemical test to check for combustion gases. Do that test first so you can determine if that the cause. Then go from there.

so, coolant leak kit and head gasket chemical are the same liquid that I am going to buy?

No the cooling system pressure tester has a hand pump and adapters for various radiator openings, looks like this, this is a positive pressure test kit. If you have an autozone or advance auto store near you, they actually rent these kits out. You just have to give them money for the price of the kit and they will refund you 100% when you return it.
2nd picture is a vacuum test and fill kit, and then 3rd is the chemical head gasket kit, it only detects combustion gases being pushed into the cooling system from a bad head gasket or cracked cylinder wall, etc.

Oh, I am aware. I have all these tools. But what am saying is do i use the chemical head gasket kit when am doing pressure test using the tools in the first picture and only for the pressure test?

No I would do the chemical test first thing when the engine is still cold, so you can run the engine with the radiator or reservoir cap off, here's a little testing procedure description on head gasket tests. The chemical test will come with instructions, once you're done with that test you can then do your pressure test. Because you can only run one test at a time since both methods require use of the cooling system opening.

if the thermostat is removed, why do you think the lower radiator hose is not getting hot? Strange, Even if the radiator is blocked, the bottom one should get hot since it is part of the water that is not circulating isn't it?

With the thermostat removed and the vehicle just sitting at an idle, yeah I would think the lower hose should at least get warm, the engine wont get up to operating temperature because the thermostat regulates that, but unless the water pump is not working correctly and flow is limited, This is the non turbo engine correct? Sorry I don't remember if you mentioned that or not, just asking because the turbo engine has an aux radiator.
You could take off the Serp belt and turn the water pump by hand and see what it feels like. I'm not sure what kind of water pump this is as for the internal workings, but I have seen water pump break the vein part of the pump right off inside and the pulley was spinning but the pump was not doing anything inside.

Non turbo. Yes, was thinking water pump. Yes, next move is to remove the belt and see. Then maybe remove the water pump.

Not sure how accurate these pictures are, and if the actual pump veins are plastic or metal, some are plastic, but yeah, I've seen them break off inside, that's a diag that can throw you for a loop. If you can spin the pulley very easy by hand, its possible it sheered off inside. It's rare but happens. Let us know, and if that's the case, take some pictures for us please.

Removed water pump, no issues there, hardly any water from the hoses except the one coming from radiator to water pump. If heater core is clogged up, could it cause stop of circulation to where the lower radiator hose stays cold? No heat from vents even though hose under the hood going to heater core tests hot.

I don't think so but it might affect the refilling procedure though, if one hose of the heater core cannot pull the air out, you may end up with air pockets. How much coolant did it take while refilling?
here is a zoomed in diagram of the cooling system hoses, the hoses to the heater system marked in red. Does this vehicle have a transmission fluid dipstick? It sounds like there may still be air pockets, the coolant spec is 15-16Liters, For an empty refill, and the refill procedure for an empty system (diagrams 3,4,5). There are a lot of small hoses on this vehicle but check that the transmission fluid just to be sure there isn't any coolant in it.
16 liters is over 4 gallons, so it's quite a bit of coolant.
When doing the vacuum refill, after you have vacuumed it down fully and its held for a couple minutes, when you go to refill, you can't let the fill hose that pulls the coolant into the system to take any air in, so use a 5 gallon bucket or some large container so when refilling there is no need to stop the refill procedure. It needs to keep pulling coolant until its completely full and it has to be down to 30inHG of vacuum so it can pull the full amount of coolant.
You can try taking off a hose that's higher up, an easy one to unclamp, so the air can bleed out, I usually check any hoses that are up the highest since that's where the air can end up, but the vacuum bleed system should have no problem pulling all the air out.

Yes, that's what i thought. They are not stupid to make it where if a heater core is clogged up the whole system just overheats. Cannot remember how much coolant i put in first. When installing thermostat and coolant flange maybe 2 or more gallons. It's a frustrating issue. I removed the hose from the bottom radiator and water came out. Same on top one, ran water through radiator and its fine. No junk or plastic from anywhere. I don't understand how temperature can go up high if bottom one is not hot and too ones you can squeeze and feel that there is not so much pressure just regular pressure. But it gets scary with the fan kicking super high and reading on scanner says 235. It could be that the reading is wrong, cause like i said the temperature usually takes time to get to halfway of cluster needle but it gets there quickly not to mention the thermostat is out. Removed the upper heater core pipe hose under engine, which i think comes from radiator then foes to the aluminum pipe, the one that has the second bleeding screw, no junk of any type. blew air into most of them and it came out fine. Is there a second intake under the top plenum? I am thinking maybe there is a clog where the coolant flange we replaced which goes into a second piece, cause the pieces were all broken and we had to spoon it out. That flange has 2 openings and sits next to the oil or water cooler under the intake. If the readings on the cluster and scanner are wrong. With the gun the temperatures are not high, maybe reach 130. And when i measured the radiator fina from in front of the car they were around 67f.

No transmission dipstick on these and no evidence of oil in coolant. Also far drives excellent no shifting issues.

Yes, i used a 1-gallon bottle to fill water twice, so removed it yes.

If it was reaching 235f the hoses would be super hot and full of extreme pressure, Unplug your coolant temp sensor and see if it reads -40f with your scan tool at just key On, engine off. They will usually default to -40 degrees when open circuited. You can also check to see if there is a 5volt reference on one of the coolant temp wires when the sensor is unplugged,.
You might be dealing with a bad sensor or wiring issue if the scan data is not the same as a temperature probe reading.
Are you meaning about a lower intake manifold? Not sure what pieces youre mentioning there, something was metal was broken that came out in pieces?

It looks like there are 2 ECT sensors.