Replacing the Diesel Tank

[Sue & Larry]

I'm replacing a black iron diesel tank on my 36-foot ketch. Should I remove the engine and replace the tank? (That's the only access but I'm not iching to yank out a well-running engine.) Or should I cut the tank in half and extract it through the cockpit seat hatches?

Sue & Larry respond:
If your black iron diesel tank needs replacing, chances are your boat is 20-plus-years old. In this case, it's probably time for a really good look at your engine, even though you say it's still running great. We think you'd be wise to remove your engine not just to have an easier time of taking the tank out but also so that it will be easier to put the new one in and still maintain your original fuel capacity.

If you opt for this route, while your engine is out, you should take the opportunity to paint and sound-proof the engine room, inspect all the electrical and plumbing systems, replace any suspect hoses and clamps, etc. We find that it's often much harder just thinking about the process than actually going through it. And you'll probably find that inspecting and renewing everything now may well save you time and headaches in the future.

When you have your new fuel tank built, consider having the fill tube extend down into the tank by two-thirds its depth. This will eliminate the nuisance of diesel fuel foaming back out of the fill or vent before the tank is full. We did this on Serengeti, and it works great. Good luck to you.