I have a 1999 Mercury 150 xr6, serial number 06788532. I can't find the model number. I have two problems. While idling at slow speeds it lossed fuel pressure and shuts off. I have to pump the fuel bulb to get it to run again. It runs fine at normal speeds. I have put a new bulb in the fuel line. Any ideas why or how it losses pressure.

The second problem has to do with putting the motor in gear. When i put it in gear it grinds, then engages. any ideas why this is happening.

The fuel problem is most likely an inward air leak, change all your hoses and fittings. The shifting problem is most likely an adjustment that the dealer may have to make.