Tim G.

I'm new to this one, so I'm looking for some input..

I put in 55 gallons at the local gas station (FYI Boat ran great before). Went for an hour and noticed Starboard engine had a fluctuating tach at 1000RPM.
I figured just crappy gas, like low octane. Boat ran OK at 3,500 + rpm.
I went to flush the engines when the boat was back on the trailer. Starboard engine was a little slow to start, and the port engine wouldn't light at all.

So, I changed the fuel filters last night. Starboard engine lit off OK. Port engine needed quite a bit of starting fluid to get going. (I hate to have to use it)
Got it running, but I can tell she isn't so happy.
I did put two bottles of dry gas in the tank as well.
Do I put the boat in the water and try to run it hard to move this gas through, and then change the filters again? or do I put another 25 gallons of 93 octane from another station in first?
Motors are '99 502 Magnums.

I had 8 years on my old boat and never had to deal with bad gas, and now I have a twin engine boat with bad gas...

Bajaforce

Tim,
I would add more gas from a different station and put in more dry gas.

BadDog

Use an electric fuel pump and suck out all the gas you are able to. Hook the electric fuel pump up just in front of the carb. Change the level of the boat to get the last bit out, pretty close to level at the tank should do it. Put about 5 or 10 gallons of gas back in as you add several bottles of drygas, this should be way more than the recommended mixture. Slosh this cocktail around and suck all of it back out again. Change filters and drain float bowls. Add a small amount of fresh gas with the correct amount of dry gas for the fuel and pull some of this through the lines and filters. Hook everything back up and test run the engines, if they are ok fill it up to dilute the dry gas mixture.

Have a big bonfire in the back yard.

blue thunder

Assuming you have water seperators, did you empty them into a clear container and let sit to look for seperation? Water will seperate fairly quickly. If you didn't do that, do and if no water is found I would filler up with the highest octane gas you can find and add octane booster. If you find you have water in the gas, the best thing to do is drain the tank.

BT

Skaterfast

Yes drain the gas,no question.Put it in your car.It will run.

Tim G.

OK.
Couple questions...
Should I even bother going back to the station to complain?

If I do drain it..
Will my little oil change pump suck it out of the fill pipe?
I could get it into my truck, but I don't want bad gas in the truck either...

Or, do I try and add a hose to the lines in the bilge and go out the hull drain??

I ran the motors with new filters for about 45 min on the hose. I'll remove the filters and pour into a glass (and drink?).

BadDog

I assume you have carbs. Questionable if the oil pump will pull fuel or not, if it did it is probably too slow. Disconnect the fuel line as it enters the carb; hook a section of rubber hose to the fuel line and the pump on the other end. You could just go straight to the tank and pull out all you can then mix the dry gas cocktail and pull it through the system. What you are trying to do is pull the contaminated fuel through the system after it has been treated. Use a 10 foot section to pump it into an alternate tank such as your truck. If it is a carb engine it will run ok if you have added enough dry gas. You can also run it into a large container and then pull the gas out of the container after it sits and the water separates some.

If you ran it for some time on the hose you may be ok. Maybe not. The water will sink to a low spot in the tank and hide in bends or pockets of the fuel system. May not get sucked back into the engine until you bounce it around some or increase the flow rate. You probably are ok though. What is your tolerance for problems on the water vs. the driveway? If there is any doubt suck it out! You will never have to be towed home from the driveway.

Tim G.

The motors are '99 502 MPIs.
Different form what you said??

BadDog

MPI's, ok find the fuel tank and disconnect the fuel line where it goes out to the fuel system. Put your electric pump there and suck out all the gas. Add some more gas with dry gas and pull it out again. Refill using correct amount of drygas and your good.

Tim G.

I know you're all seriously concerned about my water in gas situation...
So I called "Gas One" to rip into them in hopes they would pay to have my tank cleaned... Not so.
The station is only two years old, and has all the techno to monitor H20 in the gas. They pump 8000 gallons per day!
We had a lot of cold swings between my last run and the water situation. Word has it that may aluminum tank, at half full probably saw a lot of condensation in the week. We had 4 cycles of 70 in the day, and 30 at night.
I'm going to pull the lines off the motors and drain 5 gallons off the bottom of the tank and check for water..
I'll put more dry gas in the tank as well.
Went to the local Merc man and got two more OEM filters, and a new set of NGK V plugs for both motors. Time to bust knuckles..

You guys ever experienced condensation of this severity? How much water could really be in there??

Gotta fix this thing before the Miami party!!