I realise that this has been covered before so please excuse is this is going over old ground. I have just completed a Coolant change on my Sprint GT. Prior to filling with new Coolant I removed the Radiator "Vent" screw. I them slowly added Coolant via the Radiator filler cap. After about 1/2 to 3/4 of a litre Coolant began to flow from the Cylinder Block drain hole at which time I replaced the drain screw. I continued filling until the Radiator was full with Coolant flowing from the Radiator Vent hole. The Vent Screw was then replaced. I shook the bike from side to side as best I could and squeezed the Coolant hoses. A few bubbles did escape from the Radiator filler hole. I added Coolant to the Expansion Tank max line. All of this has only used 2 Litres of Coolant. As posted before the Haynes Manual gives a capacity of 2.8 Litres !!. My Triumph Owners Handbook says 2.3 Litres. I ran the engine until the Fan cut in. After cooling down the level in the Radiator is full to the top. Is it possible that I have trapped air which is why I can't get the extra 0.3 of a litre in ? Any help and advice much appreciated. Thanks.
Did you run the engine with the rad cap off? You can then see the flow when the thermostat opens. Failing that, are you certain you fully drained it?
Our Gee Like Dozers Dad said. It nearly impossible to completely drain a coolant system. I wouldn't worry you are pretty much there. Regards Joe.
Try using a leaf blower to get all coolant out. Take a look at the following video, and how much coolest comes out with the leaf blower (5:28)
