Originally Posted By: TheBeaz
If you do the timing belt yourself, make sure you get a good quality timing kit made in Japan or America that in addition to a new water pump, includes new idler and roller pulleys. On Subaru's it's critical that those pulleys get replaced every time a timing belt replacement is done because those pulleys often go bad before the belt and could take out your engine.
You can also do the Gates kit WITHOUT the water pump - the belt is made in the US but the idler/tensioners are from the OEM suppliers. Use the OEM Subaru pump or the Aisin one if you have a manual transmission model - same thing, Aisin doesn't rebox the automatic version. Do use Loctite 242/243 on the tensioner bolts, install the idler pulley last. The Gates kit also includes a small tube of it.
While you have the timing belt off, it's not a bad idea to take off the oil pump, check to see if the pump rotor screws aren't loose and reseal the 2 galley plugs on the bottom with RTV or anaerobic thread sealant and the pump-to-engine flanges, it's a common leak point on the EJ engines besides the oil separator plate in the back. Loctite 518 is preferred since it won't break off and plug an oil gallery if you use too much. You can use RTV, but in the thinnest bead possible.