BLEEDING HELL !!!!

[alibabi]

I have just fitted a new radiator, can anyone tell me when a cooling system is free of air, I have used the members fact sheet and have been bleeding my system into a bottle held above the expansion tank level and it is free of air bubbles.
However sometimes if I run the engine when cold the coolant will run out the expansion tank.

[francophile1947]

Sounds like you didn't wait till the thermostat opened - bottom rad hose should be hot(ish) to ensure stat has opened. You'll never get the air out of the system if you don't.

[alibabi]

I currently dont have a thermostat fitted
I was trying to eliminate a suspected blockage which is why I fitted a new radiator.
Perhaps fitting a thermostat is my first task.
Thanks also for private messages will be in contact soon.

[samuel]

Have you got both heater controls open? The rear matrix is the one which willl normally hold the air.

[missfixit70]

Heater controls shouldn't make any difference to the actual bleeding - the water flows through the matrices anyway all the time, the heater controls just alter the airflow across them. Switching on each heater just checks whether the water is flowing through each matrix ok & heating it. If you leave the heaters on while you're bleeding it'll take much longer as you'll be drawing the heat from the cooling system at each matrix as well as the rad, thus not allowing to get up to temp as quick & open the stat - when fitted.
If it's not bleeding with the stat out, there's a problem there somewhere, it should bleed quicker with the stat out as you don't have to wait for it to open. Is it worth trying a new cap on the expansion tank?
Why did you suspect a blockage - what was it doing or not doing?
From what you say, you are bleeding it & it seems ok, then when it's been left & started from cold, it's blowing out water? Is it drawing in air somewhere? pinhole leak creating a vacuum as it cools drawing in air as has happened with several people?