Clunk after reverse
 

2005 baja islander 496 bravo one drive . Dropped someone off at the dock today and backed away from the dock in reverse move shifter to neutral then forward and cluck. Not knowing what it is I went back to neutral reverse neutral fwd and cluck. Got the boat on the trailer and checked out the drive and with the drive at mid trim I can pull the drive up all the way to where the trim rams are fully extended. Tried the same thing on a buddy's boat his doesn't move. Not sure if it's related but I have noticed the down trim is slow unless The boat is underway forward. Sounds like reverse lock out problem but everything I can find talks about older boats. So I'm looking for help , where is he reverse lockout on my boat ? Can I fix the valve if it's stuck or does it need replaced? Thanks

Starting to answer my own question, found that the newer pumps have internal valving that controls the trim when in reverse. Looks like there is a kit to rebuild the pump 18545a1 it can be found online at alot of marine parts stores. Around 80-100$. Still hoping someone has done this to tell me I'm on the right path.