FREEING THE FLOW

Good plumbing is paramount to prevent fuel-flow interruption, which can damage a boat's engine.

- STEVE D'ANTONIO

MONTHLY MAINTENANCE

Since their advent in the early 20th century, diesel engines have been Most are robust, reliable and long-lived, provided they receive preventive maintenance, clean fuel, cooling water, and air for combustion.

When they do fail, the problem can usually be traced to a handful of culprits: deferred maintenance (a deteriorated impeller or broken belt, for instance) or contaminated or interrupted fuel, with the latter including air ingestion, an electrical fault, or a design or manufacturing defect.

This column focuses on fuel plumbing. Fuel is usually conveyed from the tank to the engine via flexible hose; in some cases, it's via copper tubing. Any hose that's used must be rated for marine fuel applications, including the ability to resist exposure to flame for a minimum of 2.5 minutes. Hose that meets this requirement is typically marked USCG A1. It should also include the name of the manufacturer, as well as the date it was manufactured. If any of this information is absent, particularly the Al rating, then the hose is disqualified for use in a marine fuel application.