The car is a 2000 Outback Legacy. A year ago the serpentine belt snapped, tonight it snapped again. I think the power steering pump is going out, the belt itself squealed once in awhile at slow engine speed when turning the wheel. Tonight before replacing the belt I spun the alternator and pump wheel to see if the bearings maybe going bad but of course I can't spin it fast like the engine. The pulleys spun good, I replaced the belt and the same thing is happening with squealing at low engine speeds when turning the wheel. I'm pretty sure the belt isn't too tight becuase I made sure it had a little play like the belt behind it but didn't want it to walk off the pulleys. Do you think it's the pump or the belt being too tight? I've always had vehies with a tensioner so it always adjusted itself unlike these engines. Any insight is appreciated! Note it has 240k miles, don't know if pump is original

If the fluid level is good and the belt isn't to loose and it squeals when turning, then chances are pretty good it's the pump.

 

For tightening, I always tighten the belt until it's a bit tought to twist the belt 1/4 turn between the pullies. (Not sure that's the best gauge, but I have not had a problem)

And by the way, I think they use atf fluid, not power steering fluid.

Yeah, fluid level is good. I can't complain because of the miles and age but since the pulley spun so well I wasn't 100%. But I can't put the pump under the stress with my hand though either.

look inside the PS tank closely while idling - if there are bubbles - you have an air leak.

 

lots of info, search air - power steering - o-ring , etc.

 

bearing in tensioner pulley - or the pulley's mount, might be throwing/snapping belts?

 

also, watch crank pulley for wobbling while running - it's 2-piece and the rubber ring can fail.

Edited April 13, 20169 yr by 1 Lucky Texan

Check the crank pulley for wobbling while the engine is running. A wobbling pulley can chuck the belt off and shred it. 

subaru power steering failures are very rare - it is unlikely to be the pump. 

 

as he just said - check the pulley alignment - i bet a pulley is bent or the crank pulley is partially separated or something causing excessive perpendicular forces on the belt, not just lateral over tightening.