Hydraulic Engine Hatch Cylinder Leaking
 

https://cimg4.ibsrv.net/gimg/www.off...8d08ccba36.jpg
It is leaking where the round casing meets the base. Probably just an oring, but how does it come apart?The top appears to be threaded, but I'm not sure how the bottom is held together.
Trying to figure out what I'm getting into befoe i remove it and prop the hatch up.

You'd have to show a better picture of it cause you cant really see anything there......but i had one ram i couldn't figure out how it went together too. Turns out after much frustration the ram itself was threaded onto another shaft under a skirt....looked it was the main shaft of the ram but it wasnt.....

Sorry, that was a pretty bad photo to go from
https://cimg4.ibsrv.net/gimg/www.off...63711fb4d8.jpg

well from the picture i would first guess to take it apart you unscrew the top knurled part and the shaft should slide out. As far as where the leak is.....if its at the base of that tube where it seems to go into the block where the Hyd lines are connected to....id guess its screwed in there....if not then its press fit in there. hard to say....

It's just a Mercruiser trim cylinder. You can buy them a dome a dozen off Ebay.
The "tube" and the "end housing" do have different part numbers but I've never seen those pieced separated. I would GUESS the tube threads into the end housing.
You can get rough with it and see if you can unscrew the tube. Worst case - you ruin it and buy a replacement off EBAY fir $60.
If you can get it unscrewed, then clean the threads on both parts, wire brush any debris off the threads, reassemble with a good anaerobic sealer (permatex in blue tube). You should be good to go. But the peace of mind is knowing that you can replace inexpensively ..

The end screws onto the threaded tube. Most likely has an O ring to seal it. I would put the end cap in a vice. Then wrap about about 5 layers of duct tape around the tube a few inches above the cap. Use a pipe wrench over the taped part to unscrew the tube from the cap. I have used this same technique to take apart a SS hyd steering ram

Thanks for the replies