Re: Tilt/Trim leaking down
I rebuild these things, but it is the off season. There isn't enough people boating during winter to keep the force tools and parts out. Individual repairs are out of the question because who wants to spend an hour taking out and putting away special tools and parts for just one system? So during off-season it might take two days or it might take two months. You might want to check ebay .... after I do a batch I often list a rebuilt pump or two.
Any decent auto-electric shop should be able to rebuild a force trim motor. It's chrysler stuff you know. Just insist on complete rust removal and internal etching/coating to prevent future rust.
Regarding doing just valve body versus pump .. here's the bottom line -
It's a pain in the butt to get trim parts on/off your boat and the more you mess with it then the more likely you are to strip out an aluminum port and cost yourself bigger headaches. So undertake the repair that best balances your total time & cost over the next season or two.
The trim motors never wear out from use. They break because of rust or oil. 3w trim motors can last almost forever. When water begins to creep inside of a 3w motor you will notice rust around cap bolts, cable fitting, or edge of gaskets. 2w trim motors last about 20 years whether you use them or not and then the rubber seals begin to break down. There may or may not be any visible signs of external rust on a 2w motor. 3w seals are a pain to install and you may as well do a full rebuild. 2w seals are easy to install and a cheap way to get new motor if you are ahead of rust. So it pays to be proactive on 2w but not so much on 3w.
As a rule of thumb - if you have 2w then replace pump assembly and be done with it. If you are ahead of rust on your 2w then put new seals on motor at same time as rebuilding valve body. If you have 3w then examine motor for signs of rust and take an educated guess. Don't try to peek inside. The very act of peeking ruins the seal. If you think your 3w motor is still watertight then just fix the valve body. You don't save any money by being proactive on a 3w (but you do cost money is you let rust fester into big problem).