Re: Coolant circulation issue - is the water pump working?
Mine was running cold and refusing to warm up. I changed the thermostat and it warms up fine now.Thermostat cost me $9.
Changes in coolant colour can mean its overdue for changing and is no longer anti corrosive. A bit of water soluable machine oil in the coolant can drastically reduce corrosion.
Brent Swain, Yacht designer, Builder, and author of "Origami Metal Boatbuilding"