Originally Posted by TheArtOf_Fast
Well I had a long drawn out reply to this thread with pictures and all. but it's been about 3 weeks now and still hasn't been "approved" by the moderators. so here is my shortened version.
the o-ring all the way in the center of the pump is wrong. OP has dash 21 listed as the size, but that o-ring (especially in FEP) is way too thin as other have posted. I used a dash 119 FEP ring with EXCELLENT results, plenty of power steering at idle and no noise. The dash 21 O-ring doesn't seal properly with the pump half and as a result you get low to no power steering at idle.
This too ^^