Bloated Gas Tank

[FreeLance]

Took the  boat over the pass today heading to Rimrock lake by White Pass.  Started in Seattle at basically sea level with the tank 7/8 full.  By the time I reached Rimrock my gas tank was so bloated that all 3 floor panels were popping up.  I took them off and there was a nice crown to the tank.  I opened up the gas cap thinking it would burp out the pressue and nothing.  So I went back into the boat and slowly put pressure on the middle panel.  Out comes about 1/4 to 1/2 gallon of gas from the fill spout.

Is this normal while going up in elevation and should I be concerned? 

From what I can tell there is not gas in the bilge and the tank is not leaking.

[DENNIS]

Mine did that the first time I took it out down to Shasta Lake.  Although it didn't push up the floor boards, it did push up those pins that you use to pull out the floor boards.  I took out the pins so they didn't tear up toes.  Since then I have had no other problems.  If I am towing long distance, Lake Roosevelt for instance, I tow with as little gas as possible.

Dennis

[bmccalla]

Gas expands when warmed. It was a good idea years ago before pumps became standardized to gas up in the morning when the gas was cool and you would actually get about a half gallon more gas than if you gassed up later in the afternoon. I would recommend not filling the tank all the way up. The Lexus engine sips instead of guzzles, so even when you start out, the gas could still be expanding.

[curtis]

Trailering long distances with a full tank makes your tow vehicle use more. At about 8 lbs per gallon equates  to 216 lbs for an "E-22", 336 lbs for a "S" or "SX 22". On the flipside it is hard to find quality fuel at times.
curtis

[bullet1w]

Gas weighs about 6.25 pounds per gallon.  Water is about 8 pounds per gallon.  I have had this happen as well.  After you burn a few gallons my floor boards go back to the original position.