Thanks to those of you who replied to my earlier thread regarding loss of engine coolant + overheating... "Yikes! First Day - Coolant leaking - HELP PLEASE!!!"
Have done some investigation work and have spotted that the plastic coolant neck filler + dipstick (bottom left of engine bay - behind headlight) has totally come away from the main coolant tank beneath it... Am I right in thinking that this should be a pressurised system + therefore if it is loose/not attached would cause coolant overflow?
Could this be part of my problem? If so how are these things fixed to the main pipe to maintain pressure as they seem to be a seperate part - some sort of sealant? Any ideas?
As I have only had the car a day I have soken to the garage and they said bring it straight back and they will resolve the problem... I guess I should highlight this to them...?
Cheers
Craig
There is an over fill drain plug on that tank.
Fish
No, the plastic overflow tank is not pressurised. When your engine heats up, obviously the coolant in the engine expands. The coolant pressure increases until it reaches 0.9 bar upon which the little cap on your AST opens slightly and allows some coolant to flow to the overflow tank. When you shut the engine down and the coolant cools down and contracts, assuming your coolant system is free from leaks, a vacuum will form in the cooling system drawing the coolant back from the overflow tank into your engine. Now, if there is a leak somewhere in your cooling system (preventing the vacuum from forming) or if the cap on the AST is faulty then the coolant system will continue to force coolant into the overflow tank without drawing any back in. Have you noticed coolant escaping from your overflow tank? Perhaps you could try a new cap on your AST ans see if that helps.