Something more I've learned since my last post. We have been having difficulties with our fuel and fuel filters, starboard engine only (in case you don't know, we've gone over to the dark side, and now live on a power catamaran).
When we first took possession of the boat in Florida, we were driving the boat north to New York for the summer when our engines lost power dramatically. Although we suspected that it was fuel filters, Peter decided to have a diesel mechanic look at the engines since the boat had been bought used and he felt that it was prudent to have a professional look at it. As it turned out, the fuel filters were clogged, and looked as if they hadn't been changed since the boat was first put into service - one looked rusted into the filter housing.
Fast forward six months and 18 months later. Again, we were having difficulties with clogged fuel filters. yes, one of our mistakes was that we didn't clean the fuel tank, but in our defense, it was difficult to do and we figured that with the amount of fuel we used that the entire tank had to have gone through the filters several times. Peter decided to install vacuum gauges on the fuel lines to give us warning when the filters were clogging up, to save us the anxiety of the engines losing power dramatically with no warning - with a seriously overactive imagination then taking over.
The guage for the port engine looked good, but the starboard gauge, right the the installation, showed elevated vacuum. Peter scratched his head, switched everything to determine what was the source of the blockage. When every possible combination had been tried, the only possible problem seemed to be the Racor filter housing itself. Lo and behold, we installed a new housing and everything is now fine.
Since then, we have heard of another boat, a sailboat, whose engine problems turned out to be a badly clogged and fouled Racor filter housing.
It was easier to deal with our sailboat's fuel problems. The tank only held 44 gallons of fuel and pumping out the fuel to visually inspect it, and cleaning out the tank was quite simple. The years we spent in the S. Pacific and SE Asia meant that much of the fuel we received was probably not filtered at the pump (filters are expensive; even in the US we've experienced pumps with badly clogged filters). We had to finally pump out all the fuel, let the gunk settle out and pump off the clean diesel at the top of the jugs, disposing of the ditry fuel/water mixture at the bottom, and clean out the tank with a rag on a stick through the inspection port. Smelly, dirty, but worth it. Fuel filters are expensive, our time is much cheaper.
Jut a heads up - skills acquired on land aren't necessarily enough when you move onto the boat.