When replacing the timing belt on our 98 at around we had a leak from the pump to harmonic balancer at the front lip seal I opted to pull the oil pump at that time because of what I had read before hand about the fasteners on the case plate this plate covers the gear and pumping arrangement to prevent poor oil pressures and damage from starving vital engine components. Disturbingly, most of the screws were nearly falling out of the plate and holes. I subsequently removed all the screws and inspected the gears and case. The remainder of the pump had very little wear so a good cleaning and a drop of red lock tight at the threads gave me a good feeling. New seal, timing belt and valve cover gaskets tightened everything up nicely. The engine was always very noisy to me but the dealer indicated that the 2.5 had very short skirt pistons used to retain the nearly same size restrictions as the 2.0l and for economy numbers. recommend replacing timing belt, idlers (there is a few of them)and water pump as the work and cost are minimal. These are available in a "kit" so this tells you how many problems develop in this area. FYI This is a interferance engine and this means if the timing belt breaks the engins valves stop going up and down as intended. Pistons in the combustion chamber however, keep going up and down until the engine stops moving. That being said, any valves open when they should be shut can and will destroy, causing piston, head and other serious damage. Happened a few years ago to a freind, a Subaru Dealer (none the less)replaced the timing belt without the rollars idlers and tensioners on a meticulously maintained 98 with close to 200000 miles on her. Needless to say the 3000 to 4000 dollar cost of a engine job put a new car in the driveway with only a apology and excuses from the dealer. Sorry for the extra wind but seriously, I wish everyone knew these issues.
the dealer took in when i had a leek and when i got it back two days later the nut came loose and started to make harrible noise so i sent it back and the guy put a lock nut on and has not came loose sense