So, between yesterday and today, I'm getting a little freaked out. The trim isn't working sometimes, most of the time it does, but sometimes it's not. And it's completely random, so I'm just wondering what it could be.

Also, I somehow managed to lose a cap for my drive, I guess? I have some pics, any ideas where I can get one? Would a marina have it?

Those caps just screw on and off. They are no big deal as far as I know.

He's right..they just screw on. There are prolly many places online to buy them. Most of the guys I know dont even have them on their boats. I believe they are just for looks mainly. Go to Mercruiserparts.com...part your looking for is #15 or #21 (they are the same). Part # 19-14842 $1.45 ea.

Awesome, thanks a bunch. Now if i can just figure out the damn trim.

Get a jumper wire (length of wire with an alligator clip on each end) and jump the terminals on the pump itself. If it sputters, misses, burps, hesitates, or giggles, I'd say its definately a pump problem. Could be a loose connection, bad ground, etc. If it runs fine with no problems, I'd guess its the switch on the dash (you can try jumping that too). Should at least get you headed in the right direction sir.

Well, yesterday, neither the trim button on the throttle nor the one on the dash were working. But today, just the throttle wasn't working, but the dash was working.

Is your throttle for trimming only, while the dash switch also is your trailer switch?
A buddies boat did same thing as yours, sometimes worked, sometimes not, and then the trim worked to different amounts.
I found his hinge pin to have loosened up and was turning, altering the contact points adjustment every time the pin would turn. The trim contact plate is turned by the hinge pin.
Just a thought to check

Your right about the dash and throttle, but there's 2 buttons on the dash, one for trim, one for trailer. Where is this hinge pin you speak of?

Ok, I guess then you can ignore my thoughts since both the throttle and dash trimming switches are not working as 1.

The hinge pin is located behind the black round plastic pucks on the sides of the gimble ring where the drive pivots up/down.

I'd start looking under the dash for bad connection between the 2 switches

Thanks, I'll start there. Is this something I can test with a check light?