NiceS4

Simplest way to do a coolant tank swap w/o draining the whole system?

eigenvector

suck out all the coolant from the tank with a pump..

NiceS4

Exactly what I was considering - but won't it let air into the hose coming out of the front?

eigenvector

not sure tho..
but i have heard people pumping the coolant out this way and it being fine..

s4net

I placed a small plastic bottle cut in half under the bottom hose. The coolant went into that and I tried to tilt the tank up quickly so some of the coolant stayed in the tank. I put the new tank in - filled with new coolant and the temp guage been fine since. It is winter here in Philly so I am not really testing the limits of the cooling system.

Mat Indukts Lambos

and will bleed out itself, no worries. I usually don't drain or suck out any, and just use vise grips on the 2 hoses to keep them pinched off.

TwinTurboTerror

And that's why there was all that air in my system after you worked on it... :-P