do I need to remove the timing belts on a 1987 subbaru 2 door hatchback in order to replace the water pump

You may want to go to the autoparts store and grab a chilton or a haynes manual. It will have diagrams and step by step instructions on how to do jobs like that

If it's an EA81 hatch, there are no timing belts, the camshaft is gear driven. If it's an EA82 hatch (three door) you have to remove the crank pulley and the center timing belt cover, but you don't have to remove the timing belts to do the water pump. If you don't know the difference, look at the engine, the EA82 engine will have plastic timing belt covers on the front, as well as have "EA82" cast into the top of the block, near the dipstick. (That's another giveway, EA82s have the dipstick up front, where the EA81 has the dipstick at the rear of the engine on the passenger side). If you need further assistance, visit http://www.ultimatesubaru.org/forum/ The picture I posted below is the EA81 style hatchback. (Note that if it is a STD and not a GL hatch, it will have the EA71 1600cc engine in it, instead of the EA81 1800cc engine, but is still referred to as an "EA81" body style)