Wide F'n Open
Join Date: Jul 2008
Location: Skull Valley, AZ.
Ok, The vent line only attaches to the water pump, the other end lies under the engine going out back towards the right rear tire. On the 660s the water pump is driven off the oil pump. You have a seal that has gone bad between the water pump shaft and the oil pump. Easy fix, remove the water pump and replace as an assembly or just the needed seals. Look at a parts breakdown of the water pump online. Where are you located? Apache Yamaha(as do most dealers) have a great parts breadown with descent prices.
Check your radiator and cooling system for oil in it! You may have to flush the system if it has oil in it. Usually coolant leaks out of that hose when the seal goes bad.
Do you see coolant in the oil?
Dirt flies when your having fun!