bleeding the cooling system?

Easiest way is to put the front of the car off of the ground so the radiator fill cap is higher then the heater core, start the vehicle and run it at about 2000 rpm's and keep villing the coolant untill no more bubbles appear.

I don't see how the radiator cap can go higher than the heater core by raising the vehicle, I think it stays the same, but if jacking the front helps I will certainly try it, although my driveway is on an incline and the front is always up.

The idea is to get any trapped bubble out of the system which can be done by lifting the front or the rear of the car while filling, it can help. What problem are you having?

Running the engine with the radiator cap off only wastes the coolant because it runs over and even when I used a funnel it filled the funnel and ran over, how can one be sure that all the air is out anyway? Since the pressure raises the boiling point, wouldn't running the engine with the cap off cause it to boil over?

You don't have to run it until it's hot, you just start it and let the pump circulate the coolant at 1,500-2,000 RPMs. Then shut it off and top it up. Then put the cap on and run it until the engine is warm and the thermostat has opened. Now let it cool off and check it, if it's low top it up. As for boiling over, it could without the cap, but most vehicles won't do that at an idle because the engine isn't generating that much heat.

Okay, i find that if i let it run with the cap off it does run over and of course, it wastes the coolant, but you are saying not to let it get hot enough to run over, right? Then there is also a theory that bleeding on a dodge ram is not necessary because it bleeds itself into the overflow chamber. I'm trying to learn, but sometimes things get confusing. Another thing
I would like to discuss is: if the cooling system is functioning as should no leaks not overheating etc. And the radiator is full why would it draw coolant from the bottle when it cools if there isn't any space in the radiator for more coolant; if i replace the coolant in the bottle each time that it cools, why would it draw more coolant from the bottle each time i do a trip and it cools? Am i making sense?

Okay, the cooling system starts off full, radiator full and bottle at full cold. You start the engine, and it heats up. As it does the coolant will expand as it heats up. (Has to do with how the water absorbs the heat and makes the molecules speed up and expand to store heat, then they hit the radiator and dissipate the heat out into the air) Now you have HOT expanding liquid. Liquids don't compress, so unless you want that full radiator to split open you need a place for it to go. On modern cars it pushes the spring on the radiator cap open and releases some pressurized hot coolant into the overflow reservoir or expands in the pressure bottle. So now the engine is fully hot, and the coolant is doing its job. You get home and shut the engine off. For a bit the engine will actually cause the coolant temp to rise even more because there is no coolant flowing. That ends and the engine starts to cool down. The coolant starts to condense as it releases the heat. As it does it starts to leave a void inside the radiator and engine. That void is a vacuum point. In a vehicle with a reservoir this is the point that the second valve in the cap opens under that vacuum, and it pulls coolant back into the radiator. This does two things, one it keeps air out of the cooling system. Rust and aluminum oxide inside the cooling system will destroy an engine very rapidly. So, to prevent that air entry into the system to help prevent that corrosion. It at the same time removes the air to prevent any from being drawn into the engine and causing a hot spot in the engine due to the lack of water flow through the air pocket.
Now in a vehicle with no leaks and a properly operating cooling system any coolant lost would be a miniscule amount through the secondary overflow tube. So maybe over the course of 2 years it might evaporate a teaspoon. Any coolant loss over that means you have a leak somewhere.
If you are saying that you top it up cold. Then drive it around and have to add coolant again within a couple of days, you have a leak somewhere. Either external, like a pinhole in the radiator that leaks out hot coolant that evaporates in the air, or internal, IE a head gasket that is starting to fail.

Being afraid that the head gasket may be leaking, i checked the compression in all 8 cylinders and it is no lower than the last time i tested it. I looked at the o2s as well it did not look like it is burning coolant, plus it isn't misfiring, maybe I'm worrying unnecessarily. So maybe it is normal for the coolant bottle to go low, and it isn't necessary to refill it to the level every time it cools? What started the whole thing though is after i replaced the radiator with one of those all-aluminum racing radiators after the 6-year-old radiator started leaking; i didn't want to go back with the vinyl tank crimped radiator. But the radiator is wider with more tubes and the pressure cap is 19psi, I'm not sure if it was a wise thing to do, i had some problems adjusting the fan shroud because it was hitting the fan at first, but i solved that problem. I think that i just need to learn the correct way to get the air out of the system when i do a repair, i plan to get myself one of those pressure test/vacuum kits, which is probably the best way to do it. Thank you for your interest and help.

Once the engine has run through a couple of hot/cold cycles the coolant should stay at a constant level, unless you have a problem. Take a look at where the overflow connects and make sure it's sealed. If you still need to add coolant after a few heat cycles, it's going somewhere. A compression test may not show it either. Want to see an interesting but technical explanation on that. Visit the YouTube channel Schrodingers Box, look for a 3-video series on a Jeep, the first one starts "did liars and thieves misdiagnose this car" Isn't the first time I've seen similar things.

Okay, I was wondering if the compression test is fool-proof, another thing I did not ask about is if the thermostat doesn't have to be opened in order to get all the air out of the system? because that is why I ran it till it got hot.

Hi Steve, I watched the Schrondinger's box videos; I happen to be a subscriber, although I haven't seen his videos for a long time; I have a leak-down tester too, so I'll certainly try that test, and the vac/psi gauge test, as well as the sizzle-test with the oil. I'll try them all just for practice. I'm not an everyday tech. so I don't get enough practice with these tests; even when I do them, I'm not very confident with what I'm seeing. Thanks for your help.

Here is the condition of some of the cylinders on my v8 I only just figured how to send photos and it is so easy. Ha

It's a good thing if the thermostat is open but the system is designed to be "burped" with it cold. I don't bother these days as I use a vacu-fill on most vehicles. So much simpler and you can use it to test the system as well. For head gaskets I've been known to pull out a few tests before condemning the engine. I'll run a leak down test then a cooling system pressure test, a liquid gas test and even stick a 5 gas detector in the coolant overflow. This shows a few of them. https://www.2carpros.com/articles/head-gasket-blown-test
It's not like the days when you could pull the heads off a small block and swap the gaskets out in a lunch break so I want to be sure beforehand.

Hmm, that last image with the piston down in the bore isn't promising, the yellow on the cylinder walls and the clean piston surface looks like coolant has been cleaning it. The coolant will get into the cylinder and the ignition cycle will blast it into steam. That steam will break up and remove any carbon or deposits from the combustion chamber. So, if you look in and see 7 cylinders that have some carbon and ash on the piston tops and valves and then find one that looks clean enough to eat off them, you have a problem.

Yes, I realize that too, only I have been using fuel additives to clean the cyls/valves because the first compression test that I did a year or two ago, the num 7 was the lowest compression at 150 and I noticed that the valve seats are dirty. I also did a leak-down and was hearing air through the intake and the oil filler. I know the rings are most likely bad, I figure If I could clean up the valves, some compression may come back, provided of course that is the problem. I don't know why the gasket would be bad though, because the engine never overheated that badly to blow the gasket; every time that I had an overheating problem, I stopped driving it until I fixed it The heads were replaced back in 2005/2006 at Bob Wilson Dodge when the spark plugs were so rusty that the technician suggested that it was more sensible to replace the heads than to spend time trying to remove rusted plugs The van was from Illinois where I believe salt is used on the roads but I bought it in Florida where I used to live and I shipped it to Barbados 11yrs ago. So, the whole engine was rusty, and it has quite a history. Thanks, Frank

I thought that the yellow on the walls meant that combustion is passing the rings, but then I remembered that I used to use yellow coolant at one time, but who knows how long it has been going on.

Hi Steve, Frank here. I have given up on the idea of a bad head gasket for now; because I did a number of tests, and none are indicating a gasket problem; I hope that the clean cylinders that you mentioned is from the gum out and other additives I used. The coolant bottle level seems to be stabilizing. But what I learned is that the new vicious clutch that I installed is not the correct one for my van....it spins like crazy after shutting down the engine, so I replaced it with the old one which is working right, stopping with the engine shutdown. When I ordered it, I did not know that some clutches are reverse clutches. the new one was causing overheating at idle only. Thanks for your interest and I learned some pointers from the paragraphs you wrote.

So, when you installed the new radiator did you remove the hose connection covers before installation? They should be red or blue.

Yes, I saved them in case I want to stopper something for a test, If I didn't it would be overheating all the time, right, and very bad. But what is different about this radiator is that it has holes that other radiators don't have and they are on the top tank on each side and stoppered with bolts, I have no idea what they would be for, if it was on a racing car, just curious as to what would connect there. What concerns me about this radiator is that it has a 19psi pressure cap and it is bigger than a regular one so I can't fit an 18, so when it goes bad, it is going to be difficult to replace it. Since I put back the old vicious clutch as I mentioned above it seems to be working fine, so I'll give it some time and see how it goes. Thanks for responding Ken.

Likely those are for secondary overflow or bleed lines or if it's a true race radiator they could be for a push feed coolant fill system that allows for the race cars cooling system to be topped up even with a hot engine.

Hi Steve, thanks for the info about the radiator; the bleed lines part interests me most, maybe I could install a bleed valve to one of those ports.

Take a picture of it or if you can find a name on it. Might make it easier to sort out what it is.

Hi Steve, the radiator is called Engine Cooler 3Row Core aluminum, through Amazon. The ports are on the same side as the top/bottom hoses with bolts stoppering them.

Is it this one? If so then those are mounting points I believe.

No, it is a downflow, that one looks like a crossflow. And the brackets are on the side and have hooks so that it can be rested on the bolts and then tighten the bolts.

Please post an image of it, there are a few that come up that will fit that truck, however it sounds like you have a very not stock design and that could be part of the problem. The OE design is a crossflow design.

My Dodge never had a crossflow, the OE one with the brass tanks that I replaced 6yrs ago was a downflow too. Besides the radiator hoses would not fit to a crossflow. you may be talking about the newer dodge rams after 2001, And I don't have a problem anymore, the new vicious clutch was the source of the problem, and I reinstalled the old one solving the problem. The new clutch was the incorrect one for my van and it was causing it to overheat but only at idle. The problem has settled down. Taking a photo of the radiator may be difficult with it installed, I can only get the top of it, but I'll try if you want to see it. My radiator on Amazon has the word engine cooler written on the front in blue although it didn't come like that in reality.

Okay, is this a van or a truck? The original header was for a 2002 Ram truck. The vans were interesting sometimes but around here GM had the custom builds (conversion and passenger builds) and Ford got the commercial side. (Buses and ambulances) Even split on box trucks. Dodge always seemed to be the odd man out. Either way I'm glad you got it fixed. I think you mentioned it had blowby back there, you might try running a couple cans of Berryman's B-12 through it if you can get it. I've had it free up rings more than a few times. Thanks for using 2CarPros.

yes, my Dodge Ram is a 2001 Cargo Van, it also has only one cat. converter one fuel control for both banks of the v8. All videos that I see with v-engines have separate fuel control for each bank. Thanks for the tip on the Berryman's B12, I'll check on it.

Steve W. is one of our best please let us know what happens.

Hi Ken, I already said that my problem is solved; the thread is so long that we probably lost track of what it was about in the first place: it started with getting air out of the cooling system. After replacing the radiator and the vicious clutch, the dodge ram was overheating, but only at idle, but I at first thought that maybe it was air and I did not get it all out .It turned out that the new vicious clutch that I had installed was the cause of the overheating because it is the wrong one for my van. I reinstalled the old one and now it is fine. The original thread seems to have disappeared. I'm sure that Steve knows what he is talking about, and I appreciate all input and interest in my problem Thank you, Frank

Glad you could get it fixed, thanks for letting us know. Please use 2CarPros anytime we are here to help.