On the new XC-4 motors that KTM introduced in 2008, it was found the water pump seal was installed backwards from the factory, with the spring oriented in the wrong direction. It seals, but eventually fails.
My pump developed a leak shortly after a week of King of the Hammers 2021. x hours and x miles
To access the seal,
- Remove the water pump cover bolts 8mm and cover to expose the impeller
- Remove the impeller bolt 10mm
- Pry off the impeller and spacer
Now the water pump seal will be visible, and if installed backwards, the spring will be pointed towards the engine and out of view.
To remove the seal, force compressed air up the weep hole to pop out the seal.