Fuel leakage twin 370 Cummins/2000 31TE

[amber jj]

Last weekend we had the Amber JJ hauled to her winter home about 45 minutes away from her home port.After arriving unloaded and blocked I climed aboard to check things out and when I lifted the hatch found quite a bit of fuel in the bilge.
I will back up here a bit and tell a little more of the lead up to this.The Wednesday before I took her to the marina to top off the fuel and add stabilizer and to have the holding tank pumped.The fuel is full and head back to my slip and change the oil and filters in the 2 engines and genny.Finished up, the bilge is dry,and went home.Saturday morning is pouring rain when I got to her slip. I started her up and took her around to the ramp for our 9 A.M.appointment.It is a 10 min.ride at a idle.While going over the starboard engine kept slowing down slightly,so I would tap the throttle up a bit.This happened a couple of times.I arrived at the ramp and shut her down.We were able to slide right onto the waiting trailer.I never bothered opening the hatch until after we reached our destination.That is when I saw the fuel. There was some rain water mixed in the fuel too which made it look even worse.
The next morning I went back over to vacuum up the mess and wash out the bilge.After that I stuck a hose in the starboard strainer and started the engine and let the engine run for 15 or 20 min.I figure the problem is the star. engine because the spilled fuel is on the star. side of the star. stringer and down into the star.shaft log.I checked the feed and return fuel lines the injectors and pump.Everything is dry.
The only other thing I can come up with is the fuel vent line may be broken somewhere and sloshed out during the road trip,but why did the engine lose r.p.m.,Or is just 2 things happening at the same time.Right now I can't get at the vent hose to see.I will bring a inspection camera to worm below the deck and tank at a later date.
Any words of wisdom or past experiences would be appreciated Bob

[amber jj]

Two weeks ago my hydraulic trailer came and loaded Amber JJ on the trailer and left boat and trailer on site for Friday afternoon delivery to the lake. When Val & I went to clean up anything loose for the trip the next day and I lifted the hatch the centre bilge and starboard shaft log are full of fuel again. I left it figuring I would clean it up when I got to the slip. The driver said when he took off the bilge pumps spewed fuel onto the lot and road when he left and then carried onto the ramp and we launched. No more mishaps.I cleaned up about 3 or 4 gals of diesel in the bilge and have not moved the boat since. Last weekend I lifted the deck floor and checked the fuel gauge sending unit gasket and the fuel lines manifold plate gasket also I took out the 3 starboard vent lines because the fuel is only seem to be coming from the starboard side and running through thr gar board holes and into the main bilge. The only other hose I have not checked is the starboard filler hose,but it does not leak while I am refuelling.This is not just seepage it a full out gusher. You would think what ever the problem is it would be as plain as the nose on your face.There is not even a wet spot on the tanks which there are 3. I've checked where they are bolted together at the top and I cannot see any seepage along the edge and there is a inch and a quarter space at the bottom and I can't see any splits or holes.I haven't taken her out at all this season for fear of splashing out more fuel.The engines can run all day and not a drop leaks,so there no problem in the suction or return lines.Any ideas? Thanks Bob

[TomA]

On my 32 + 2 single Cummins 370 the fuel equalizer line (1 1/2") hose between port and starboard tank had a crack in the hose. The cracked hose was close to the port tank so that was where the fuel accumulated. Might want to check that with a clean absorbent cloth. Tom A

[amber jj]

Thanks for the reply but this is not a weeping leak it must actually pour out. There is literally gallons in a matter of minutes. This why it stumps me not to find the leak.