Engine Bathed in Diesel

[Johnatkatys]

Model Year: 2017, Vessel: RT25 SC, Volvo Penta D3
The fuel line beneath the fuel filter broke and the engine compartment quickly flooded. We pumped out 45 gallons of diesel. Wish I'd taken a picture, but it was a rough day.
For some reason the bilge pumps never ran. Good thing - that would have been a real mess.
So here's the question: What parts might be vulnerable to this?

Here's what we have so far:
-- alternator - could that survive?
-- serpentine belt - easy to replace
-- bilge pumps - were they already failed, or did they fail fast?
-- engine oil - if diesel leaked down the tube
-- air intake filter - there was a lot of foam

What's missing?

 

[Johnatkatys]

I have more info now. (Volvo Penta D3)
1. The engine sputtered and ran rough at low speed. We shut it down.
2. We discovered the full bilge immediately. There was about16" fuel in there - high enough to splash the manifold and create smoke.
3. After discussion with the coast guard and the marina we were allowed to tow the boat in to the fuel dock and there, we pumped the fuel out and into 9 5 gallon plastic containers. (That's how it got mostly clean and that's how we know 45 gallons.) The guys didn't spill a drop!
4. The bilge pumps did not activate because they use an electrical continuity sensor. Fuel has little to no conductivity.
5. From the fuel dock they towed it to a yard 7 miles away.
6. At the yard, they blocked it and then finished the cleanout, and then had a tech do a diagnosis.
7. Here are their points: (my comments in parens)
a) the alternator is shot. it generates 0 volts on the bench. (not too surprising, an AI search suggests the lacquer on the windings might be dissolved by diesel fuel, and the bearings would probably also would be washed of original lubrication)
b) they recommend changing all belts and tensioners, including the timing belt, which is not sealed.
c) all the tensioners and pulleys have been washed/flushed of their lubrication and should be replaced
d) what broke was the fuel filter and the water sensor had come loose !!! (this is not very satisfying as it's not clear to me how BOTH could come loose, but he did make the comment that there was an incorrectly sized O-ring involved) He told me that once he put it all back on and properly tightened it there was no further leakage. (There is a button right there that tests)

Aside from the dead alternator, it might be possible to actually run the engine as-is. How long it would last would be anyone's guess but it's likely something would seize up. If the timing belt broke, there could be severe engine damage.

Note: The above reflects the opinion of one technician and his boss. I'm taking it to a different shop for repairs and we may learn more there.

In terms of what others might do, my pre-float inspection will now include manually feeling the fuel filter and sensor under it to make sure they feel dry and tight. It's kind of hidden under the engine cowl. I will be testing the bilge pumps with water to make sure they still work. In a way, their failure to react to diesel was a blessing - we sacrificed my engine for what might have been a pretty ugly oil spill in the Puget Sound.

 

[Johnatkatys]