Tilt/Trim issue

[CAMAN]

Hey everyone, I've talked to a couple boat mechanics I know about this and they don't really know what this issue could be without taking it apart. Motor is '86 (I think) Mercury Classic 50 45hp. Last fall I came down on a rock as I was stopping the boat and I believe the skeg hit the top of the rock and pushed the entire motor up. Since then my trim has been acting up. It tilts and trims in the up direction just fine, it also tilts just fine in the down direction but when the motor hits the trim rods it stops moving and if I keep holding the down button it will actually start going back up. I can get it to trim down all the way if I have the motor in gear and I repeatedly bump the down button about 50 times it will inch its way down, but is really annoying.

Did I blow out a seal in the pump? Is it a DIY fix or is it best left to the pro's?? I'm fairly familiar with the entire assembly of the unit, last spring I had to disassemble it to replace the brushes, I'm just unsure of where to start and what to look for.

Thanks in advance!!!

[boatfixer]

Have you tried to use the manual release valve to see if it will go back down all the way? Try that first a few times and cycle it up and down. If that doesnt work, then you more than likely have an internal valve issue.

[CAMAN]

Ummmm....yeah...thats another issue you just reminded me about. One of the previous owners of this motor decided to put loctite on the release valve and the last owner broke off the head of it. I tried removing it when I had it apart but couldn't get it to budge. Hate to hijack my own post but am I able to drill that out clean the threads up and replace it with a new one or is it way to complicated in there to risk? Thanks for the help Bruce!!

[boatfixer]

OUCH! You run the risk of getting contaminents into the system. I'd say at this point.....it's gonna have to be taken apart.

[CAMAN]

Alright, thanks Bruce, thats what I figured. Is that something a guy with a strong amount of technical knowledge could tackle or are there specials tools needed and best left for the pro's? I haven't gotten around to buying a repair manual for it yet to see whats needed.

Thankfully I got a great deal on the motor and it runs awesome so the the little work I have put into so far (impeller,brushes) is not unreasonable.

[boatfixer]

There is gonna be some special tools needed, for instance, you will need a special spanner wrench just to get the rams out. There are also valve settings inside that are factory preset, knowing what to disassemble and what not to gets a little tricky. To be honest with you, its been a real long time since I've been into one like yours so at this point, I'm not sure what to tell you to look for other than a releif valve stuck open or a seal thats blown off its seat.