I recently purchased an old skeeter bass boat in pristene condition except for one detail that I cant figure out. The boat is an 1984 Skeeter Strada F80 with an evinrude 60 horse. The trim works perfectly in nuetral but when I take off in the water no matter what position the trim is in it trims all of the way down and I canot raise it until I stop and in nuetral, then if I try yo raise it and take off agin we start back to the begining.

Any help would be nice

The part about it trimming itself down while under way sounds like a hydraulic valve not sealing well.

even if it is out of the water though when it is trimmed up and I put pressure on it , it will stay up

Sounds like you might have a short in the wiring to the trim switch on the throttle. It only does it when you move it forward to put it in gear, then you might be pulling a wire or shorting it when moving it forward. When you get on the water try trimming it up a little and then shift in to reverse and see if it still does it.  If it doesn't do it in reverse, I would check the trim wiring in the throttle. HTH.

First, make sure it has trim.  Many of those old motors didn't come with tilt and trim and a lot of people added and aftermarket tilt unit.   THis is just one long cylinder that tilts the motor up, it will not trim the motor and will not raise the motor under power.  If it has tilt and trim, it will have the one long cylinder and two short stubby cylinders on each side with just the rams sticking out.

If it has the trim cylinders, make sure the manual release valve is fully closed.  

From there you may have a bad relief valve in the unit or bad packing in one or both of the cylinders, or a couple of other problems.

I had a similar problem a few years ago on my Evinrude Jet. I have power tilt and trim and it kept leaking off. I had to have the cylinders redone. New packing and wiper rings. Its been fine ever since.