Whats the best method to make sure all air is bled out of the cooling system?
Best way to bleed the cooling system?
SooperDave
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Whats the best method to make sure all air is bled out of the cooling system?
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Are you talking about your Z? If so, fill the radiator to the top, start it, let it run and keep filling until the thermostat is open. That'll suck the level down again. Then add coolant to where you want it and cap the radiator. Done.
Why? Do you have an air pocket or are you worried about getting one?? If you have one you can take the rad. Cap off and jack up the front of the car about 2-3 ft and the air pocket will just rise to the top...or you can use a pressure tester and pump up the system full of air (about12-15lbs) for 5 minutes or so and that should pop any air pockets you have! IF YOU HAVE DONE SOMETHING TO YOUR COOLING SYSTEM(FLUSH OR WHATEVER) AND IT IS NOT GETTING HOT OR OVERHEATING I WOULDNT WORRY ABOUT IT!
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simple, drill 8 1/8" holes in the t-stat flange, install it and refill the radiator reservoir after you've driven the car a few miles
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I ALWAYS do this mod. :yes:
X3 simple insurance:thumbsup:..
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Why 8 holes? The good quality stats come with 2 I think. There will come a point that there is no reason to have a stat if enough fluid bypasses the opening and closing stat.
As for air, if you have a pocket trapped in the block you can fill the block right at the thermostat then install the stat and housing if you need to. Keep in mind there is susposed to be a couple inches of air space at the top of the core for fluid expansion under pressure. Cycling to hot and having the stat open is usually all that is needed for the circulating fluid, pressure and expansion to get rid of most air pockets...
In more modern cars with recovery systems it becomes more critical to have the system topped off and purged of trapped air pockets...
As for air, if you have a pocket trapped in the block you can fill the block right at the thermostat then install the stat and housing if you need to. Keep in mind there is susposed to be a couple inches of air space at the top of the core for fluid expansion under pressure. Cycling to hot and having the stat open is usually all that is needed for the circulating fluid, pressure and expansion to get rid of most air pockets...
In more modern cars with recovery systems it becomes more critical to have the system topped off and purged of trapped air pockets...
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And I would never run AIR. Fill it to the brim and let the recovery system keep out corrosion. You do have a recovery tank,,,,,, don't you?
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Its my 406 in my sig. It will sit on 180 about 90 pct of time. But will drift up to 200-210 every 5, 10 min or so. And then drifts just as quickly back down to 180 for a while. That's why I thought maybe there's a pocket of hot air causing the brief spikes. I have 3 very small holes that I drilled into the t stat. The carb still needs to be jetted properly, I'm not sure but I'd assume its a little lean at cruise speeds (same jets as my 302).
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Sticking stat.
Best way to get air out is fill slow, with stat out. Then install stat, fill to the top and turn on your electric water pump for about 15 minutes, maintaining level at desired cold height. Done.
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I read this wrong earlier. I don't drill 8 holes, I just drill one.
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i always take the heater hose off the intake manifold and fill until it just starts to trickle out of that hole. hook the hose back up, top off the radiator while squeezing and releasing the upper radiator hose. when you get it full with this method, the entire system is full, except for maybe a little bit in the upper most heater hose itself.
put the cap on, put some coolant in the overflow, and start the car. after verifying no leaks, go for a drive to get it up to temp faster- a 5 minute trip around hte block will get the engine warmer than 20 minutes of idle time. once it build pressure, check for leaks, if no leaks, then shut it off and "burp" the system by either carefully cracking the cap a little bit or by using one of those caps that has the pressure release lever and flipping the lever. once the pressure is released, seal it back up and walk away from it for a few hours to allow the coolant to cool down and suck in what it needs from the overflow.
do it this way and unless you have a bad head gasket or something, there will be no air in the system.
put the cap on, put some coolant in the overflow, and start the car. after verifying no leaks, go for a drive to get it up to temp faster- a 5 minute trip around hte block will get the engine warmer than 20 minutes of idle time. once it build pressure, check for leaks, if no leaks, then shut it off and "burp" the system by either carefully cracking the cap a little bit or by using one of those caps that has the pressure release lever and flipping the lever. once the pressure is released, seal it back up and walk away from it for a few hours to allow the coolant to cool down and suck in what it needs from the overflow.
do it this way and unless you have a bad head gasket or something, there will be no air in the system.
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