Petrol in Bilge

Petrol in Bilge

Report Text:

Twelve months ago, after having 2 new 150  outboards fitted to our recently purchased second-hand RIB, we had problems with water in the fuel which got past the remote fuel/fuel filter, and the two engine filters, one of which we understand was supposed to stop the engines if it detected water.  As a result we had an expensive repair not covered by warranty.  We tasked a local dealer to drain the water and test the tanks for leaks, as we had smelled petrol fumes. The boat has built-in petrol tanks, located under the deck.

Two months ago when perhaps for the first time we filled both tanks to the brim, we again smelled petrol fumes, and carried out a test of fitting extension tubes the fillers, and then immediately noticed petrol on top of the part of the tank we could see.

When we lifted the deck, I was shocked to see that  the bilge was full of petrol and that electric control lines from the console to the engines had been laid loosely on top of the tanks, and that insulation had started to fray.

CHIRP Comment:

It was fortunate that this situation had not lead to a major explosion. We ascertained that the RIB had been brought ashore and not being used pending resolution of the safety issues.

We were subsequently able to visit the reporter and the  boat and noted that due to concerns on the integrity of the petrol tanks, new tanks had been ordered. Professional marine engineers were carrying out a thorough risk assessment of the arrangements of the fuel tanks and control lines. Their recommendations included:

  1. Ensuring that, in the event of a petrol leak, gas would not be able to pass from the bilge into the console which contains electrics.
  2. Passing the control lines through gas-tight ducts.
  3. Securing arrangements for the replacement fuel tanks.
  4. Fitting gas alarms in the bilges, if practicable.