About 3 months ago, my mothers 95 Teg RS (auto) had the timing belt and water pump replaced as part of our regular service schedule (the car has close to 200km) Two weeks ago the heater core blew causing coolant to leak on to the floor mats on the passenger side (cost $1000 CND). Now just today the radiator blew (seals at the top have come apart). The rad (Koyo brand) is only 15months old and the car has only been driven for 15000km (or something like 8000 miles) since it was last replaced.

My question is, is it possible that the mechanic who installed the water pump did a faulty job and that is causing us to experience all these other weird cooling system problems? Doing a search on this website doesn't reveal much about blown heater cores (I nearly flipped when I heard that part had to be replaced). What else could be behind this and the blown rad? ANy thoughs would be much appreciated!