water leaking into stern thruster cavity RT 25SC

[blifland]

We were getting significant leakage in the stern thruster cavity of our 2011 RT 25SC (I placed a temporary auto-bilge pump to take care of the leak).
At the 2016 Rendezvous, a Ranger Tug fellow (sorry - forgot who) located the leak source - at least one of the 6 bolts securing the thruster tunnel/assembly was leaking (looking at the motor from inside the boat - it would be the 8:00 o'clock bolt or from outside 4:00 o'clock bolt). He recommended that I remove all the bolts and caulk them.
As of today, I removed the bottom three bolts to start - all three were quite bent - bottom one really badly bent and no caulk on any.
Question: is there any reason why I could not (or should not) replace the original type bolts (#3 square drive truss head) with hexhead bolts; putting the bolt head on the outside of the boat and the lock nuts on the inside? Would it be best to use ones with threads all the way to the head or use ones that are threaded about 3/4 on bolt bottom?
Any other suggestions about this?

Thanks for any info/help.

Barry & Leslie "Keep On Tuggin"

 

[Andrew Custis]

Hello. I think it would be fine to use a hex head in lieu of the truss style that were originally used. I would use an all thread style instead of the ones that don't have thread to the end of the bolt.

Thank you!