Am I right in saying the clear bottle behind the rad on the passengers side is just the overflow for the coolant? So to check the levels I only need to worry about the level in the header tank? Just been cleaning the engine bay and noticed the tank next the the rad is on minimum and want to make sure there's nothing to worry about.

 

Nothing to worry about. No harm in topping it up to the max though

 

There's a question, why would you need to top up the overflow tank?

I'm currently all out of fresh stuff so I'm guessing a full system flush would be best as the new coolant would be a different brand/type.

 

People go on about keeping this `expansion` bottle topped up. I don`t see the point. I ran my Scoob for almost 3 years without touching it and had no problems...after all it`s an expansion tank so there needs to be room

 

You will be fine as long as you dont mix red with blue/green(ethanol glycol)

The blue and green will mix fine.Its the red(oats) that you shudnt mix.

 

Its not an overflow tank. Irs an expainson tank thats why it should be kept at the correct level. Yes as the coolant gets hot and expands pressure build up and the valve in the header cap releases coolant into the botte. What also happens is once you switch off and the coolant cools the system sucks coolant in from the expansion tank keeping the header tank full. If the expansion tank is empty the system will suck air in possible leading to an air lock

 

correct