Fuel smell /venting issue?

[grasshopper73]

Have a onboard enclosed fuel tank. After I filled up for the first time this year and got the boat tuned up I noticed an overwhelming fuel smell in the below deck compartments. checked all the fuel fill and supply connections and the tank but didnt find any leaks. All connections are tight. There does not seem to be a separate vent off of the tank anywhere. Could it be that the tank is vented through the flip fill cap on the side of the boat? If so obviously its not working correctly. Does anyone have any suggestions on how to properly vent the tank? I cant have fuel smell on all my vests, rods, bags, etc. This boat was purcahsed last year, not new, a 98. I never had a problem like this on any other boats I have owned.

[LongLine]

Check your hoses real good. I had a leak in mine a while back & it drove me crazy. I found it on the bottom of the hose laying against the hull. Any permanently mounted tank should have a separate vent line/hose to a fitting on the outside of the hull.

Tom B.

(LongLine)

[grasshopper73]

Thanks. Iam going to work on it again tonight. Looks as if the fill tube is double walled.??? Inner tube would go to tank, outer to vent back at flip cap. Ever seen that or am I looking at it wrong? Limited room to work they don't make these things very convenient.`

[fdny76]

Sorry to ask a dumb question, but did you run the blower while fueling? I forgot once and the stench lasted a couple days.

[LongLine]

Never seen that GH. I don't know why any boat mfg would do that.

Tom B.

(LongLine)

[grasshopper73]

Ive got an older boat: 1998 20' Grumman Deck boat with a 115 Johnson. Had a nicer rig but got rid of it to build the house. Enough of that, at least it gets me on the water! Im still setting it up as best I can, a far cry from my previous rigs. Still working on the fuel smell and no blower.

[grasshopper73]

Okay found the vent tube had to cut a larger hole in the deck floor but i got it. the vent runs to the top of the gas fill inlet port, there is a little screen and a rubber grommet there that should probably seal off when the lid is closed. Also in my searching found a orange label in the storage compartment that states that gas fumes are flammable (NO ****) and there is no venting provided. So does anyone have any suggestions on how to vent? There are large and small holews in every compartment. Do I plate them and seal them off to prevent fumes or put a vent in the deck floor to help with venting? Litlle confused as to the best way to remove the fumes. No leaks on Hoses, Fill hoses just has a double flange on top not double walled the entire length after closer inspection. Need a

[krenzermarine]

Your fuel vent does sound to be acceptable and is actually used in the new boats today by most manufactures. The fill neck actually has the 1.5" fuel "into the tank" line and in addition a small vent line (3/8") running from the tank back to the fill neck with a 3/8" screened hole. Sometime in the manufacturing process or during a repair that vent line can be pushed down below the top of the tank and cause fuel (when you fill up full) to trapp in the low spot, thus vapors can't move back and forth during expansion / contraction. To cure this 1. find the low spot in the hose and lift it allowing the fuel to runn back to the tank. Or 2. plug a small hose into the vent inside the fill neck and blow it out ( you will most likely have to remove the screen with a pair of needle nose pliers).

Problem is that this usually causes difficult fueling (fuel spits back out the fill neck on your hand) not a strong fuel smell in the boat. I think you have a leak. The tune-up may have something to do with the fuel leak. Carb adjustments???? Water sep.??? During wintrerization, summerization and tune-ups a tech. can easily lean on something and cause a very time consuming problem.

Good luck

Tim Habecker

Krenzer Marine.

[jimski2]

I found that the fill hose gets hard with age and can leak gasoline into the bilge area. You fill the tank up, raise the bow up to drain the bilges and gasoline leaks from the fill hose where it enters the tank.. It is hard to access and tighten. I gave up on the large tank and use six gallon portable tanks now. I can fill them up, close the vent and do not have to deal with gasoline fumes, moisture and alcohol fumes.

[ray koziatek]

PLEASE EVERYONE who owns a boat take at least the basic boating course where you will learn gasoline vapors are

heavier than air and can pool in low spots thus the reasoning of opening all hatches and vents....slight smell in boat

almost normal kinda like fillin car with window down .........but a strong or lingering smell ya better find it before it finds

you!!! krenzer Marine. has some great ideas and Its nice to see or hear other proffesional opinions from others who

care ...Hank and Jimski2 have also been there with their helpfull and proffesional info ,and when i see one of them have

responded to a concern , I always read their replys ...They Are Always Ready To HELP with their many,many (3 more

manys for hank) years of experience . It is people like this who help make this site so GREAT!!!

Ray K.

[grasshopper73]

Thanks to everyone. I did all I could do to try and fix the issue. I finally took it to a different marine shop about an hour away. He called me yesterday sid he didnt find any leaks but a part on the lid where the vent is supposed to seal off was broken so they put a new fill cap and spout. He also added some vents to the floor. He sid there were basically no other vents on the boat. I also had him replace the fuel fill line and the vent line as well as a precaution. He sid theat they were still in good shape. Better to be safe than sorry! Thanks Again to everyone for the help!