Hi there, I have never had the pump off of my E6-350 but I'm thinking that it does have a flat, or missing tooth on the drive gear to slide on one way only. I would not turn the engine over with the pump removed just in case. To set the valves get yourself a service manual as it will explain the proceedure perfectly. You must have a way to "bar" the engine over by hand with either a breaker bar, or some way to turn the engine by hand to bring the cyliners that you are going to adjust the valves on to TDC. You then loosen the locknut of the rocker arm at the side opposite the valve stem bridge and adjust the clearance between the arm, and the valve stem bridge while pushing down on the back of the rocker arm to open the gap. Using a screwdriver to hold the adjusting screw in position, tighten the locknut and recheck your clearance to ensure you are still correct. Follow the firing order of the engine, (1,5,3,6,2,4) and adjust the valves in this order. Just bar the engine over till both rocker arms for the cylinder you want to adjust are loose with clearance. This is the area you need to watch closely. For instance turn the engine a little further than when you first notice one valve just stopping to move. If you don't go a little further than this point it is possible for you to be on the "ramp" of the cam lobe and not in the position the adjustment needs to made in. I'm only talking moving the crankshaft another inch or so from the point when one of the rocker arms stops moving. If you adjust your clearance while on the "ramp" of the cam, the operating clearance will be way off when the engine is running. If you don't have access to a service manual I can scan the proceedure for you in a .pdf file. PM me your email address if you need it. Rob