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coolant fill

ksurfer2

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Is there a proper way to refill coolant to an engine that has been completely drained?
 
Mix it concentrate coolent 50/50 and fill. Or buy the premix and just dump it in.

Run the car for a minute or so, check it and top it off if needed.
 
I like to leave the cap off and run the engine until the thermostat opens and circulation begins. That method gets the air out. Then top off and you should be good to go.
 
I like to leave the cap off and run the engine until the thermostat opens and circulation begins. That method gets the air out. Then top off and you should be good to go.

^^This^^ Never put the cap on until you see coolant moving. That tells you the thermostat is open.

Living in a warmer climate you don't have to have the antifreeze mixture as strong as 50/50. Just have it mixed for the coldest it gets in your area. The more water the better for displacing heat from the engine. Only use distilled water to help with corrosion and rust in the system.
 
I agree with only putting in enough antifreeze for your area. One more thing, if it's an older car only add enough fluid to cover the cooling fins. The top of the tank allows for the water expansion. People fill them to the cap, then it blows out the overflow tube because there is too much in there and they wonder why and think something is wrong.
 
I filled the entire system with distilled water. Then after initial running to be certain the thermostat was working, I had circulation and zero leaks I drained the radiator and then filled it back up with straight antifreeze, giving about a 40/60 Anti/water mix that checked out pretty good on the coolant tester.
 
Buy a spill free funnel. They work great. Pull the temp sending unit out of the engine and add your coolant through the funnel slowly until it comes out sending unit hole. Replace sender and continue adding coolant until it backs up into funnel. Run engine to burp air until t-stat opens and both radiator hoses are hot, adding coolant as necessary to keep level just barely in sight in funnel. Kill engine, let cool and remove funnel. Recheck level in radiator. No variables this way.
 
Perfect funnel.. top off an oil bottle.
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I think the conventional green silicate anti-freeze is the right stuff for our cast iron engines.
 
Yes on starting it and letting it get to temp with the cap off. You can fill it all the way up if you desire, it will find its own level eventually but if you don't have a recovery bottle it will be puking a little out while finding that level. I installed a recovery bottle on mine and filled it halfway up, that way the system will never draw air during fluid expansion/contraction, but can still expel it if there is any left after initial startup. I don't want any air bubbles in mine with the 100+ temps we get here..
 
Burp it and allow 2” to the cap so you don’t get the car show puke. Green only.
 
Is there a proper way to refill coolant to an engine that has been completely drained?
I just figured out a way. Pull the top rad hose to expose the thermostat. Take a heat gun and heat the thermostat to make it open and allow trapped air to escape and full the radiator until coolant is at the thermostat. Your 90% there. Figure the only way to get air trapped in the heads out is to run the engine but at least I know the engine block is full.
 
Just drill a1/16" hole in the thermostat for a constant air bleed like the Japanese engine thermostats with a jiggle pin. No air locks. I've done this for years.
 
^^^^^

That said, I've never had an air lock in a small or big block Mopar. Too many guys here that have lived through the Chevy cross flow rad horrors it seems...
 
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