Seems every time i pull my boat cover off, there is a little gas smell in there. Is this normal ? Should I look for a leak ? Boat is a Monterey 190 with Volvo 5.0GL.
Is it faint, or strong? I had a boat with a similar situation. I think the smell came from when I had a leak in my power steering cooler line. Maybe it was coming from the grease I pumped into the u-joint/bellows. It definitely seemed like a petroleum based smell but in my case I know it wasn't gas. If it is gas, don't use the boat until you sort it out.
I would look at your carb area first before looking at your tank. Start at easiest area's then work way back. Sometimes a match helps find the leak the best.
When my boat sits for a long time I get a faint gas smell when under the cover. Hot and cold weather expands and contracts the fumes and then vents out. My cover also covers the filling cap. Once I take the cover off it goes away.... It goes without saying that you should look for leaks....
I would look at your carb area first before looking at your tank. Start at easiest area's then work way back. Sometimes a match helps find the leak the best.
Ironically, the match trick works for finding natural gas leaks quite well. As long as you have a sniffer and verify that there is not enough gas in the atmosphere to go boom, a match can be very effective. The catch is that if you have a sniffer you don't need the match trick.
Thanks for all the reply's everyone. The smell is not real bad, I know it is gas. It goes away after cover is off. I only smell if after the boat sits outside for a few days. I will have to see if the cover is over the gas tank vent. I wasn't even aware that boats had a vent line. My cover does cover the fuel cap as well. I don't remember smelling it last year at all, but right now the tank is completely full of gas which i have yet to do before.
Even if it isn't gapple, drafts could push it into the cover. Mine is about a foot away and like you, a couple days and I won't smell a thing-a couple weeks and it's there......probably no worries ....
Hope it is not a leak, some years back had a boat with a similar gas smell, not strong but cover did enclose the vent and that was the issue. However the good note about this slight gas smell was I had no spiders in my boat!! My dad hated spiders and had his boat in a lift. Each weekend when the cover was removed he battled spiders and hated it to the point where he did not want to go boating. A friend suggested he crack open the fill cap on his OB fuel tank and allow a small amount of fuel vapor inside the boat....we did that and guess what ...no more spiders.
Hope it is not a leak, some years back had a boat with a similar gas smell, not strong but cover did enclose the vent and that was the issue. However the good note about this slight gas smell was I had no spiders in my boat!! My dad hated spiders and had his boat in a lift. Each weekend when the cover was removed he battled spiders and hated it to the point where he did not want to go boating. A friend suggested he crack open the fill cap on his OB fuel tank and allow a small amount of fuel vapor inside the boat....we did that and guess what ...no more spiders.
Gasoline vapors from any source are heavier than air and will remain in the lowest part of the boat--the bilge. That is why your I/O should have and you should religiously use a bilge blower before starting the engine.
Any carb-equipped engine will ALWAYS smell like gas, and will very slowly vent gas to atmosphere. Look at the diagram for (or better yet, disassemble) a carb, there are various circuits that have direct pathways inbetween raw gas and atmosphere, and none of those circuits completely close up with the butterflies.
Just checked my tank lines. I have one big line from the fill going out the fuel cap and another small line going to the cap. Could this be my vent ? Does the cap have a vent hole somewhere possibly ? I don't see it.
