How long until coolant level stabilizes?

[rationull]

On cooling systems with unpressurized expansion tanks (i.e. radiator has a pressure cap, but the expansion tank is effectively open to the atmosphere) how long should one expect it to take for the coolant level in the expansion tank to stabilize (assuming the temperature is about the same every time the level is checked)? In my experience the level always drops for a little while after draining and refilling as air bleeds out of whatever crevices it's stuck in.

Watching the coolant level in our truck since I just did a drain/refill along with another job, and I just thought I'd see what kind of anecdotes are out there so I know if/when I need to start looking for a leak.

 

[LeakySeals]

A couple of drive cycles/days should be enough.

 

[artificialist]

Does your cooling system use a bleed screw?

If it does, and it isn't used properly, coolant level may never be where it belongs.

 

[mechtech2]

When you initially fill it, get it hot enough to let the thermostat open up. Then get it filled as much as you can, and put the cap on. !/2 full reservoir.
A couple of days is good, but may take a week of hot /cool cycles.
BTW, use the heater - it may be a valved type that opens for flow.

 

[rationull]

Good call on the heater, pretty sure I have had it on. AFAIK this system does not use a bleed screw -- not in the manual in any case. I think the level has gotten pretty stable although it went down probably 1/8 inch in the reservoir over the last couple drives. Hard to tell since it can fluctuate with ambient temp.