This water pump i have is the newer metal style, after taking off the cover to replace the oil pump shaft seals and orings, i noticed the impeller is kind of stiff and hard to turn....it did not leak before i took it apart since i have had this engine running. My question is...due to all the other pumps i have checked and turned the impellers, it just seems to hard and not like the others i have come across.....is this normal..has anybody else ran into this before, and what was your outcome...replace the seals, the whole pump or just run it.