Stalled in rough water, kinda scary...

[mkino]

1991 Sea Ray 225 BR 7.4 carburetor, mechanical fuel pump

Returning to Dana Point from Avalon (CA), pretty rough conditions, 3-4 foot seas with lots of wind waves. Boat was getting tossed around a lot, sometimes a bit violently. I didn't have a lot of gas in the tank, but enough to get back. As I'm underway on plane (around 3000 rpm) I lost power, had a few soft backfires, but kept it alive by revving it in neutral. It came back to life after I nursed it for a few minutes, got back on plane, then about ten minutes later it happened again, and this time it stalled. Six very stressed out women and girls were on board, not a great situation!

I thought it might be sucking air into the fuel tank pickup because the water was so rough, maybe it was sloshing the gas too much? So I took one of my 5 gallon gas cans and dumped it in. Started up OK, slowly revved it, power came back after 30 seconds or so, then I had no more issues on the last 45 minutes or so getting back to the harbor.

Any ideas as to why it would happen? Ideas for further troubleshooting? Close call!!!

 

[Scott Danforth]

Never have less than 1/3 of a tank of fuel

 

[tpenfield]

If you were low on fuel, it is conceivable that the pickup was sucking air as the fuel sloshed around in the tank.

Like Scott said, have more fuel for a matter of safety.

FWIW - I actually ran out of fuel in 4-5 foot seas, but we were close to shore. Had to throw the anchor out and wait for SeaTow.

 

[mkino]

Thanks for the input gentlemen! More gas in the tank next time for sure.

 

[nola mike]

If you have some water at the bottom of the tank, that can get sloshed up as well.

 

[harleyman1975]

Rule to live by is 1/3 out 2/3 back.

 

[wahlejim]

As a kid, anytime we went out on Lake Michigan, my dad always had a 6 gallon reserve tank on hand, stowed under the rear seat opposite the trim pump. It had a line ready to go with a plug in it and he had a hose clamp and nut driver stowed with it. He explained to me that if the lake became rough (which the great lakes will do without notice) and we ran into that situation, he could unhook the main line, plug it with the one from the reserve, hook up the reserve, and get going in under 30 seconds. Thank goodness we never needed it for ourselves, but we did help some people out with it once or twice.

If you have room and are going off shore, it might be something to consider.

As dad used to say, I have never heard of anyone saying they had too much fuel for their trip

 

[H20Rat]

If you have some water at the bottom of the tank, that can get sloshed up as well.

The pickup for fuel tanks is from the bottom... Any water would have immediately found its way into the engine. If anything, rough water actually would HELP a water-in-tank situation, it would agitate the water and distribute it.

(but on that same note, if there was a lot of spray, not impossible that a poorly designed fuel cap was letting in water)

 

[dingbat]

My fuel tanks are never below a quarter tank for just that reason.

An active fuel management system is your friend. I have active fuel flow and fuel level management. I know exactly how much fuel I’ve used and how much fuel I have left

 

[nola mike]

The pickup for fuel tanks is from the bottom... Any water would have immediately found its way into the engine. If anything, rough water actually would HELP a water-in-tank situation, it would agitate the water and distribute it.

Not necessarily. If there's just a bit of water lying below the pickup, rough seas are enough to mix it up with the gas. Running low on gas would mix that water in a smaller volume.

 

[dingbat]

Not necessarily. If there's just a bit of water lying below the pickup, rough seas are enough to mix it up with the gas. Running low on gas would mix that water in a smaller volume.

Not my experience and it happened to me twice in one week.

Gas and water don't mix. E10 and water don't mix beyond 0.05% concentrations, thus phase separation.

Water stays on the bottom of the tank. Fore and aft rocking motion coupled with gravity piles the water up at the lowest point of the tank.....at the pickup.

10 miles from shore....no sputter, nothing.....dead. Racor full of water. Removed the fuel line from the motor and used the primer bulb to suck a plastic water bottle full of water off the bottom of the tank. Drained the Racor (drain type) and made it back to shore.

Took the boat home and raised the front of the trailer with the front loader. Sucked a quart of water this time. Evey thing fine and dandy...or so I thought.

Next time out, same thing. Wasn't messing with it in the slop. Called tow boat..

Long story, short...circumstances the week before combined to create an issue with the vents on the gas caps. Quick fix... no problems since

 

[nola mike]

Gas and water don't mix. E10 and water don't mix beyond 0.05% concentrations, thus phase separation.

Well, take a jar of gas, add some water, and shake it. You don't have a layer of water on the bottom anymore. Until you let it sit for a while.

 

[dingbat]

Well, take a jar of gas, add some water, and shake it. You don't have a layer of water on the bottom anymore. Until you let it sit for a while.

”dispersed within isn’t mixing.

 

[nola mike]

Ok, you win. Although neither the pickup nor the carb cares whether the water is in solution or suspension.

 

[dennis461]

Hold on, does the boat have a fuel filter water separator?
My guess is the sloshing and low fuel level made your mechanical pump suck air which leaned out the carb for a second, and backfired.
Or fuel bowl sloshing dumped extra gas in throat.