Loose bolts. 1977 Mercury 500 50hp

OK forgive me because I do not know what this is called. See if I can get this right.

OK you have the motor mount that connect to the transom and then you have the bottom of the motor under the power head, lower unit? Well these two attach to each other with 3 bolts, two of mine are REALLY loose, to the point we think the motor might fall off one day, no telling how long it's been like this though. So I tried to tighten the top two and the just turn, guessing there is a nut on the inside somewhere, question is where and how the heck does one get to them?

I got a manual from JIM but this part of the lower unit magically is not talked about it all 557 pages.

Talk to the guys on www.iboats.com
These guys know their motors

Can you post a pic of the bolts?I may be able to help.

Those I believe are the motor mount bolts(lower).Your mounts are probably shot.

any idea how to get to them?

You have to pull the power head to get at those mounts. Its not as hard as it seems just takes time.(Maybe because I've done it a few times on various motors for motor mount reasons.) #-o