Thread: Adding coolant from empty

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After putting a new 5.7L engine in a 96 Chevy pickup I had a hard time getting the air out of the block. At least that's what appeared to be the problem. I filled the radiator with two gallons of antifreeze and one gallon of water and fired her up. The water coolant went down maybe a quart so I topped it off. I ran the engine for about 5 minutes waiting for the thermostat to open, meanwhile the temp gage hit about 260 degrees. I shut it down and waited a bit. The radiator gargled and I was able to put about another quart of coolant, started back up for a few minutes and temp was at 260 again. this process went on for about a half hour before it finally purged and the temp went down to 190 degrees.
Is there a better way? Should I fill the block with coolant first?

-Kevin

When filling a previously empty system, I always take off the heater hose closest to the thermostat housing and fill the radiator until the air is out and coolant starts to appear, then reattach the hose and finish filling. This usually gets all of the air out of the block and the heater.

Make sure to get a thermostat with the air bleed hole in it next time.There is a little 1/8 inch hole on the thermostat to let the air thru so the engine does not air lock.

Open heater core valve before refilling. Or leave it open all the time, Heater core is an extension of the cooling system.

Thanks for the advice!
Any thoughts on running the engine "air locked" for 5 minutes or so? Potential damaging from overheating-hot spots?

-Kevin

Drain 1/2 the coolant out.......Start the engine and let it heat up until the stat opens. With it running, slowly add the rest of the coolant. With it circulating as you add, the air all comes out.