While tightening the starboard spray rail on my '85 tricab, I cut a hole on the starboard bulkhead that is normally covered by the nightstand and was greeted with the following sight:
That is in fact one of the copper fuel lines that is resting on the spray rail attachment bolt. The amount of contact was enough to cause some corrosion, but not enough to cause any noticable wear on the fuel line. After I took the photo, I polished the fuel line in order to facilitate making a good visual inspection.
Since the subject fuel line is not supported immediately adjacent to the bolt, it was able to move enough to make contact. The fuel lines were no doubt run by hand at the factory, so it is possible that a similar or worse condition exists on other boats. On the tris with the fuel tanks under the aft side bunks, you (probably) have two (or four) opportunites for this condition.
You can access this bolt by drilling a hole in the bulkhead that is about 6" forward of the aft interior bulkhead, and 14" up from the top of the outboard stringer. You might as well make a big hole, because the bulkhead there is non-structural. I recommend a hole saw with a short pilot bit, or an oscillating tool like a Fein Multi-master that provides good depth control. Not only are the fuel lines there, but on the '85 tri, so are the vinyl vent hoses.
Hey -- isn't there a thread on "winter projects"? Performing this inspection would make an easy project that might serve to make future boating seasons safer.
) <<and besides, you promised me 'boat cooked' dinner >>