bleeding air from your rad /cooling system how is it done i believe there's no air in there but it seems like my rad is building up pressuris so id like to try to bleed itif i can .if you know how to bleed the system please let me know .thanks kyle
I don't think you bleed a radiator. Pressure builds up in a cooling system/radiator, it's normal. If I'm wrong somebody will come forward.
That is usually done when you drain and refill the system. Did you do that, or is it just having a problem? A bad head gasket can put combustion pressure into the system. What engine do you have, did you do anything to it recently, more info please.
yea i was having heating problems so i redid the rad hoses and t stat .so yea i did drain and fill the system .. the engine is a 350 chevy that has about 20 miles on it straight off the crate .no oil in the waset or water in the oil
I don't believe in bleeding the cooling system. Air bubbles float, and gather at the top of the radiator, and that's what your looking at when you remove the cap and look inside, period. If you have some weird situation where the cap is NOT the highest point in the system, then you need to determine that high point and put a pet**** there to bleed air out. In a "normal" system, no
i gotta agree with groucho......How accurate is the temperature gauge? They can run safely up to 230° with it under pressure. If there are any leaks it will not be under pressure and therefore will boil at 212°. i'm looking on the internerd to see if it could be pumping in reverse.
Huh?? It is very possible to have an air pocket in the engine or somewhere else. What do you think the hole in the thermostat is for? Maybe I deem this more important than others due to the fact I worked at Honda, Acura and BMW dealers in the past, and those vehicles MUST be bled. As a habit, I fill up the system on say, a SBC, with the thermostat out. Eventually the coolant starts to come out the hole. Drain a little off, and plop in the stat. I take off the top radiator hose and fill it, then stick it on the rad. Then top up the rad. Start upengine and let it run until t-stat opens. Typically the level goes down. I wonder why....oh displaced AIR. Fill it back up, place a new, proper pressure cap on, and you should be good to go. Now if your vehicle is modified to where this might not work, I've had to jack up the front of the car to make the radiator opening or the thermostat housing the high point of the system. If you have a remote coolant filler tank, even so more need to do the above. I have seen alot of new motors and old overheat from a poorly bled system.
When you "re-fill" a radiator, the thermosstat is closed at the time and any air that is in the engine block normally can not escape past the thermostat. So at the we always drill 3 little 1/8" holes around the perimeter of the thermostat. So when filling this allows the air to escape up the rad hose. It will not hinder the cooling or operation of the thermostat. An air pocket can cause heating problems.
Some "older" hot rodder told me about that, what excactly is that going to accomplish.???? Just wondering.
why drill holes when you can simply get the motor up to temp so the thermostat opens at which point the system burps and you top off the radiator.
im going to try this .thanks man it seems like a good way to go and i drilled a 1/8 in the t stat already befor i installed it
It gets the air out faster.. Picture a thermostat in your hand. When its all closed up, theres only a small hole with a little loose piece of metal stuck in it. That is to let air past the stat when closed. Mind you, small hole. So putting a few more in the outer ring makes more air p*** through. When air is trapped, it causes overheating. It prevents the water from occupying the space it is in, and when heated, the air expands, pushing more liquid out of the block. At some point the liquid boils and is forced out of the engine, along with all the coolant in its way. Hence the need to purge the air out.
My wifes nissan,s heater wasnt working rite (not putting out heat at idle) so I done some investigation and found that I had to bleed the air out of the system by putting peice of wire/paper clip under the rad cap and closing it back then I took the overflow tank off and hung it up on the hood latch/catch in a manner so that the antifreeze would flow towards the rad. (like a funnel effect) Then I ran the car at 2200 rpm for 10 or 15 minutes with the heater on. I shut it off and put everything back in place and to my suprise the heat worked perfect from then on.....................may be a nissan thing???
I worked on Toyotas, Hondas and Acuras; sometimes came across a car where therer would be a byp*** hose (or the intake on some Accords) that would stay high-and-dry. I'd pull byp*** hoses (especially to that wax pellet on the Accord intake), and occasionally heater hoses, and get 'em burped that way. I've done the 'hole in the thermostat' thing. I only use one hole; the more you put in, the slower it'll warm up (but the easier it'll burp that one time). I also used to use a funnel that had replaceable bases; different ones to fit different radiators. Snap-on sold it to me, so it was probably only 10X what it should have been. I'm sure the average crafty HAMB'r could think of a way to solder a big 2-3 qt funnel to an old radiator cap. Anyway, I could start the car, let it run up while I was picking up my tools, and watch it burp. Another .02; keep collecting them and you'll have enough for a phone call. -bill
i was told by an engine builder to take half a paper match and fold it in half. then you open the thermostat and stick the folded match in to hold it open and install everything else as normal. the match holds the thermostat open to let air escape and then dissolves into the coolant.
Remember, you must have a recovery tank to run the radiator full to the top or when you shut down the cap will puke out the overage onto the ground. If you are not running a tank, take notice of where the water level is after the first puke, and don't fill above that level. My 40 Coupe with original radiator and 350 ran cool and never puked with the water at 1 1/2-2" below the filler neck, but add acup or two above that and...barfarama.
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