Fouled gas in tank-What to do?

[nightstalker]

My fishing buddy has a 90 HP Merc. mounted on a 19' CC with a 40 gal. built in tank. The engine runs a few minutes on the tank and then starts to sputter and then dies out. When run on an auxilary tank, the engine runs fine. He has tried adding stabilizer, engine refresher, changed the water/fuel filter, etc. with no change. Do we have to drain the tank and find a way to clean it out, of is there an easier way to do it?<br />Stalker

 

[briannh1234]

Re: Fouled gas in tank-What to do?

siphon it. Carefull not to drink any. Then give the gas to someone you hate. Might want to put some seafoam in the new gas when you fill the tank again.<br /><br />- Brian

 

[wvit100]

Re: Fouled gas in tank-What to do?

You sure the vent in operating correctly. I'd check the vent tube and anti siphon valve to make sure they are working before getting rid of all the gas.

 

[nightstalker]

Re: Fouled gas in tank-What to do?

Checked these first and seem to be working fine.<br />Stalker

 

[detroitmedic498]

Re: Fouled gas in tank-What to do?

There is a hand operated bulb siphon that works better for draining a tank. There may be a large amount of water in the tank from condensation. drain it off, remove the tank, allow it to dry out and air out then replace it with clean fuel. I had the same thing happen, with both a car and a boat motor. I had to do it in both......good luck.

 

[Mark42]

Re: Fouled gas in tank-What to do?

After it sputters and dies, pull one of the float bowls and see what is in there. Probably water. You might be able to siphon off the water from the bottom of the tank, especially if the boat can be set in a fixed position. Like on the trailer with the boat tilted up or down so the water collects at one low point for ease of siphoning. It does not take much water to choke out a carb. <br /><br />There must be too much water for the separater to handle.

 

[Fishin' Mission]

Re: Fouled gas in tank-What to do?

I just had the same problem...I drained the gas. I have not had a chance to refill the tank. When I do I am adding some tank cleaner first.

 

[jtexas]

Re: Fouled gas in tank-What to do?

Don't use a shop-vac or a drill-operated pump to defuel:<br /><br /><br /> stupid human tricks

 

[KRS]

Re: Fouled gas in tank-What to do?

LOL, jtexas... made me laugh! That is officially a "Holy Crap" story!<br />.<br />I had a "professional" contractor fill a hole in a wall (behind a gas water heater, pilot light ON) with expanding foam, you know? the highly flammable kind! He was *surprised* when it went POOF! Luckily the door was open and it wasn't too much of a confined space.

 

[llfish]

Re: Fouled gas in tank-What to do?

Last fall I had, had being the key word, a neighbor who was draining the gas out of a 1965 Corvette that he was getting ready to store for the winter. He used a shop vac. A week later if died from Burns he received when the car and vac blow up.<br /><br />It is surprising the amount of static electricity that a shop vac will generate. If you want to test it try sucking up a pound of flour with a shop vac and then touch a good ground.

 

[rayjay]

Re: Fouled gas in tank-What to do?

I have worked on motorcycles that had sat for many months. Of course the carb would be terribly gummed up and needed cleaning and I always drained the gas out of the tank and flushed out the tank with parts washer solvent to get the dirt and rust out [ plastic tank, how did rust get in there?? ]. I then almost always put the old gas back in, straining it through a couple of blue paper shop towels. They always ran good and these were small single cyl, 4stroke dirt bikes, very critical on their carburation. Gas has to smell really bad before it won't run ok. You may be able to mix the fuel 1/2 and 1/2 with fresh gas. Try some of the boat gas in a lawn mower.

 

[imported_Curmudgeon]

Re: Fouled gas in tank-What to do?

Try your tank with a different fuel line. If it runs fine, you solved the problem. If you end up draining the tank, go to a junk yard and get an electric fuel pump, buy enough fuel line to run safely from the boat to suitable receptacles and have it.

 

[JRJ]

Re: Fouled gas in tank-What to do?

Fuel delivey drivers carry a paste that applied to a probe and stuck in the tank, will tell if there is water present. The water will be at the bottom and you may not have to drain the whole thing.