fuel vapor smell on 330 express

[duckhunter]

strong smell in cabin but only while underway, intermittent, doesn't seem to matter how much fuel on board, any suggestions? 2005 model

 

[journeyman]

This doesn't sound good... I would hazard a guess that fuel is in your bilge. Check each and every access point you have to the bilge area fore and aft. No sparks on board until source located. If it does smell like gas anywhere down there you have a leak somewhere in the fuel system - tank, fill / vent, fuel lines, separators - that needs to be found before something bad happens.

 

[everwhom]

x2 - fumes in the cabin is bad news, and could lead to a serious explosion.

Have you tried opening the hatch to where the washdown and livewell thru hulls are? I would imagine you would be able to smell fumes there. If it's only happening underway, you may have a leak in one of your fuel lines so it's only leaking when gas is being pulled to the motors.

If the fuel lines are original, you should consider replacing them all at this point anyways. I did that last year on my '03 because I had air leak in one of the lines.

 

[jip40]

strong smell in cabin but only while underway, intermittent, doesn't seem to matter how much fuel on board, any suggestions? 2005 model

Does it occur when the genny is running or at all times - I have a gas smell coming from the exhaust from the genny - tech serviced it and said running too rich - he needed to get some additional parts to correct problem - Checked with a few sources & they said it is not a critical issue - I do not have fumes in cabin though - but might be air flow of exhaust into cabin

 

[seasick]

My first step would be to open floor access plates and cabin lockers before starting the motors(or turning on the batteries) to smell for gas. Since very little of the underfloor fuel plumbing is under a lot of pressure, a leak in the lines is less likely but a tank leak can not be ruled out. As mentioned that could cause fuel to enter the bilge or other under deck areas. Since tank leaks often occur on the bottom of the tank, the amount of gas in the tanks doesn't make much of a difference.

Let us know if the gen set was running. Also confirm that the odor is gasoline as opposed to exhaust fumes. As mentioned, really rich exhaust will smell like gas Usually if the mixture is too rich the exhaust will look dark or blackish. Lots of exhaust in the boat could indicate a problem with the motors lower case ( the old corrosion issue.) the motor might sound off/noisier)
Try running on one motor at a time to see if the smell is there only on a specific motor. The fact that the smell is intermittent could be a lot of things like the wind directions and speed, roughness of the seas, angle of the hull etc.
Check the fuel sender flanges and fittings for leaks. At angle and with bouncing, fuel will splash up against the bottom of the sender flange.
Tell us if you have the issue with the aux tank in use or not. Try running the aux tank empty to see if the smell goes away.
Be careful. If you open the hatches or inspection plates and smell gas, you shouldn't turn on anything including the battery switch until the below deck areas are aired out.
Good luck

 

[Legend]

A few weeks ago I was traveling and stated to smell gasoline. I stopped and opened the floor hatch over the main fuel tank. The area around the fuel sender was wet and smelled of gass. I noticed a small piece of the sender gasket was ripped or deteriorated. When I go back to shore I got a replacement gasket for the sender and the smell and leaking gas disappeared. Good luck, I hope you fix is as easy as this was. PS If you have never replaced a fuel sender, it is a god idea to place use a permanent marker and put a mark on the tank and the sender so it will be easy to reinstall in the right holes. There are 5 screws and the holes are not symmetrical. you can still figure it how they fit but it is a lot easier if you place the marks.

 

[journeyman]

Does it occur when the genny is running or at all times - I have a gas smell coming from the exhaust from the genny - tech serviced it and said running too rich

I would like to know if he has a gas or diesel generator. If it's diesel, then there is no mistaking it for gas engine exhaust. Not sure when Grady went diesel. Either way, exhaust in his cabin is not a good situation to have if that is the problem.

 

[seasick]

A few weeks ago I was traveling and stated to smell gasoline. I stopped and opened the floor hatch over the main fuel tank. The area around the fuel sender was wet and smelled of gass. I noticed a small piece of the sender gasket was ripped or deteriorated. When I go back to shore I got a replacement gasket for the sender and the smell and leaking gas disappeared. Good luck, I hope you fix is as easy as this was. PS If you have never replaced a fuel sender, it is a god idea to place use a permanent marker and put a mark on the tank and the sender so it will be easy to reinstall in the right holes. There are 5 screws and the holes are not symmetrical. you can still figure it how they fit but it is a lot easier if you place the marks.

When replacing the sender flange gasket, the tank should not be full or near full since it is possible for fuel to spill out. Also don't over tighten the flange screws, snug is good.