RB25DET Water Pump – Don't want to stop midway because if it dries you're going to have to redo the entire process.. Now we're ready to install our water pump first Josh is going to apply some ultra blue permatex liquid gasket on the mating area of the water pump ; you want to make sure you just put a nice even film on the mating edge so as not to get any in the water pump or into the water passages ; now you'll see that there's grooves on the inside of the water pump and the gasket will go ahead and fill in upon installation and remember when you install the gasket liquid gasket you don't want to put too much and you don't want to stop midway because if it dries you're going to have to redo the entire process.