I just removed mine. The top unscrews. The instructions were at http://www.mowersdirect.com/manuals/51347_51358_Man.pdf. I had to use a Sears tool No, 45535 to wrap a heavy rubber-type band around the bottom and a oil remover tool that fit nicely on the cap. It unscrewed once I had the leverage.
Jimmy D
March 2010
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