tilt/trim issue

Hi I am new to this forum and am hoping someone can offer some suggestions. I have a 89 Johnson 85HP outboard on a bass boat. The tilt/trim mechanism seemed to be working fine, as well as the engine, so we went to launch the boat and were unable to lower the motor. The tilt motor was seemingly working (in other words i could hear it), but still the foot would not lower. We finally pulled the thing back out of the water and started messing with the hydraulic system. We tried adding fluid, but it was full. Bottom line is the thing will raise but not lower. I do not have a service manual or any reference material on the tilt/trim assembly. Any help/suggestions anyone could offer would be appreciated.

Re: tilt/trim issue

make sure the tilt lock did not fall in place. some have them some don't.