won't get up and go

[jack walker]

I got an 88 slingshot ultra 810 with an 88 Johnson. gt 200 with a 24 raker on it the boat only waghts 1300 lbs 18 feet 6 inches long hydraulic jack plat it don't want to com out of the hole when it does get up it runs about 50 mph at 5600 rpm. it won't lift the bow of the boat

[boats.net]

First make sure your engine is running in top. Has it done this since you have had it?