Fuel smell in the cabin of my Tomcat

faceplant

Hey everyone! Here's another problem from the new guy.

When I first go into the cabin of my Tomcat, it smells like fuel. It goes away pretty quick when I open the windows and door, but its worrying me since I only started noticing it after our last trip.

From what I've read in the forums, I should be looking for leaks from my fuel lines or tanks. I stuck my head in all the access hatches and didn't find anything that looked wet on top of the tanks. Those hatches did smell "gass-y" but I'd expect that since i'm smelling the top of the gas tank....or should I not be able to smell it? When I stuck my head in the aft compartments to check for fuel in the bilge, I didn't smell any fuel. Same with the forward compartments under the berth.

The smells seem strongest in the access hatches in the hanging locker, port step, starboard step, and under the sink.

Anyone have any ideas as to what I've gotten myself into or what else I should be looking for or how I should be checking this out?

Dreamer · Posted: Tue Jun 07, 2011 1:19 am Post subject:

Can't give you any particular clue but you do need to follow up on this ASAP. The only place you should smell fuel is the fuel tank vents on the sides of the hull. Hose fittings on the tanks and sending unit seals would be where I would start. Be safe..

starcrafttom · Posted: Tue Jun 07, 2011 1:21 am Post subject:

what type of heater stove do you have? is it a wallas? beat you it is leaking a little. run it and then shut it off and place a paper towel under it for a while , couple of hours, see if it is dripping. You should not have any gas fuel lines in the cabin.

on edit: also check the cap to your wallas fuel can and all those lines.

faceplant · Posted: Tue Jun 07, 2011 1:58 am Post subject:

Thanks for the extremely fast replies.

I'm definitely trying to resolve this as soon as possible. I've got a call in to a local mechanic. Hopefully he can come by to check it out soon.

starcrafttom, it very well could be that. the trip where the smell started was my first time running the wallas for any length of time. after i checked all the access hatches for the fuel tanks i tried smelling the fuel in the wallas tank. i'm new to disel, so i wasn't sure if it'd smell like the general "fuel smell" but it didn't smell like what i was smelling in the cabin. i'll definitely try the paper towel trick tomorrow morning.

jennykatz · Posted: Tue Jun 07, 2011 11:06 am Post subject: wallas

It's the Wallas ,My Wallas stove will smell when you get a little wind on the starboard side .Check the fittings and gaskets on the 2 gallon tank and the fittings going into the stove tighten them up if looose, also make sure the hoses are higher then stove. Check out Wallas web site they will explain how the stove has to be installed I had to readjust mine so the smell went away

Pacificcoast101 · Posted: Wed Jun 08, 2011 12:47 am Post subject:

I have a Wallas stove as well and any speed above 15 knots make the fumes caome back into the boat. I'm currently down to about 1/2" of fuel in the bottle but the smell is still strong when we are moving.

Alli Cat · Posted: Wed Jun 08, 2011 10:34 am Post subject:

I had fuel smell last summer in my 2007 Tomcat. It was leaking at the fuel hose/squeeze ball on one side. Easy fix.

Fred

faceplant · Posted: Thu Jun 09, 2011 2:11 am Post subject:

you guys were right on. it was the wallas stinkin up the boat! over the past few days the mystery fuel smell was getting less and less noticable. today while testing out my wallas, i let it run for a while and the fuel smell from before was developing in the cabinet under the sink.

getting the wallas to run was a whole different story...i'm glad i've got this forum to search through. when i tried to start up the stove yesterday, it seemed like the stove didn't have enough voltage to turn on. i started my engines, and accidentally forgot to turn off the stove before hand. all lights on the stove went out and it stayed dead. today i called scan marine, expecting someone to tell me to bring it in for repair, and instead getting a really nice guy that helped determine which model of stove i had and more in-depth steps for troubleshooting. he pointed me in the direction of the in-line fuse between the stove's power cable and the battery. after learning how to use my new multi-meter, and poking around in the back of the boat, i found the offending blown fuse, replaced it, and got the stove working again.

so now i guess i should be checking out the exhaust, or is it normal for the cabinet under the stove to smell "fuel-y".

thanks again for pointing me in the right direction guys!

starcrafttom · Posted: Thu Jun 09, 2011 2:41 am Post subject:

it should not smell a lot but will smell some when ever it is running. but there are a few things you have to check out. Is the out exhaust plugged? being this is spring and bugs and wasp like make nest you could have a nest in there. If you ran the heater you killed the bugs but not the nest. pull off the exhaust hose in the boat and blow it out with air.

water is another one. if the exhaust tube routes lower then the exhaust hole before running up to the heater it could hold water. if it does shorten or re-route the exhaust tube.

also make sure the exhaust fan is running in the right direction, not likely but does happen. i don't know why but mine ran backwards once and filled the cabin with smoke. hope this helps.

faceplant · Posted: Sun Jun 12, 2011 3:32 pm Post subject:

Im thinking the wallas was a red herring. The exhaust was clear and i havent used it for a few days. The smell is still somewhat there.

What are the chances that my port fuel tank is corroding? I've got some pictures that I'll post when I get home. What's freaking me out is that on the bottom back edge of the tank it looks like it has some sort of tape going about a quarter of the way. The tape is starting to peel back and it looks like there is an old dried up puddle stain where the tape ends. The rest of that edge looks white and like it's corroding.

The starboard tank looks a lot different and cleaner as far as I can tell.

Should that be the case, does anyone have an guess as to how much it would cost to replace?

thataway · Posted: Sun Jun 12, 2011 4:39 pm Post subject:

The port tank will be easier to remove if necessary. I would get a borescope down there and take a good look at the aft edge. (or you might be able to put a camera on a monopod and take a photo of the tank (using a remote) You should not have any bilge water which regularly gets on the tank. It is possible that they left a piece of duct tape on the tank, and water got under the tape.

Unfortunately fuel tanks are not always made of the corrosion resistant alloy that they should be made of.

I would be surprised if the tank is corroded thru at this point--usually they are good for at least 10 years--and most commonly 20 years. If properly prepared and mounted, they should be good for a much longer time! However, there could be a pin point weld defect. The tanks should have been tested at 1 to 2 PSI before they were installed.

journey on · Posted: Sun Jun 12, 2011 5:16 pm Post subject:

That smell has been there long enough. And as you know, gasoline fumes are heavier than air, so if a fuel tank is leaking and you can smell it inside the cabin, ti's time to really do something. That hold might be full of fumes.

Triton didn't build your TomKat, but they must be familiar with it. So take the boat up to them and let them check it out. Or any competent boat yard you trust.

This is not a time for guessing, but a time to find what's going on. Before you blow "it" up.

Boris

faceplant · Posted: Sun Jun 12, 2011 7:45 pm Post subject:

yeah i'll give the local yard and triton a call tomorrow to see if they can take a look. the smell went away for a few days, which is why i thought it could have been the stove. trust me, the last think i want to do is blow up the boat!!

here are the pictures:

Pacificcoast101 · Posted: Sun Jun 12, 2011 8:14 pm Post subject:

faceplant · Posted: Wed Jun 15, 2011 5:18 pm Post subject:

thought i'd post a follow-up.

one of the mechanics said it was definitely a gas smell, but not really strong. he said since there isn't visible fuel in the bilge or any visible leaks, i should keep an eye on it but not worry about it for now unless the smell gets a lot worse (or gas in the bilge).

i'm getting a second opinion from another guy on my same dock who is also a mechanic. he hasn't noticed the gas smell, but seems pretty concerned about the corrosion. from other pictures i took, it looks like theres about an inch high segment of corrosion around the bottom seams of the tank. its pretty disheartening that my surveyor and i didn't catch this in the pre-purchase survey!! now i know for next time. its crazy how hard the tank is to access!

i'm waiting to hear back from mechanic #2 as to if he thinks i should replace the tank.