I bought another used drz it kept over heating. I found bolts that should not have been in the water pump and conecting hose. The impeller was wrecked and snaped off the shaft. When I tried to install the new oil seal it just fell in the hole like it was too small. I thought the oils seal had to be driven into place? Mine fit loosly into place, I checked there is only one part number for any drz oil seal. Any ideas?