Crisis Avoided...now water in gas...good story, but need advice

[smiles16]

While boating on the river this weekend, we decided to beach the boat on an island for a little exploration. When we returned to the boat (a 17' Sterndrive bowrider), the current had shoved it on-shore further than I did initially. After a couple failed attempts to shove it, I decided to giver her 'ell in reverse. Well it worked....sort of. When she finally broke free I was too slow to drop throttle, then I hear screams from the girls sitting in the back.... I looked over my shoulder to see water pouring over the stern and quickly shifted forward while flipping the bilge switch...Crisis avoided, or so I thought....

So, after my stomach settled and my blood pressure calmed, we decided to continue our cruise. This was until I started noticing a hesitation in the engine, and decided to make my way to the dock (that was four miles away). Well, I almost made it (within 50 yards actually) when the engine finally gave it up. Luckily a passing pontoon gave us a tow to the dock. I decided to investigate immediately after I trailered it....YUP nothing but water in my filter.

While my boat was pretending to be a submarine, water must have traveled down the then submerged fuel vent. So, I have learned a couple valuable lessons as far as my driving is concerned, but now I am looking for some advice concerning my engine/fuel setup.

First, If the water separating fuel filter fills with water, does any significant amount make it to the carburetor or does it shut off flow completely?

Second, I know there are options available to keep water from entering the tank via the tank vent.

Third, what should I do about the carb if water did in fact make it through the filter? I was cranking on the starter quite a bit trying to get out of barge traffic.

Last, do I have to waste the near full tank of gas? My gut and knowledge says yes, but does anyone else know a way to not waste so much gas?

Any other thoughts are welcome too.

-Thanks

 

[alldodge]

First, If the water separating fuel filter fills with water, does any significant amount make it to the carburetor or does it shut off flow completely?

Yes, with the motor dying it has water in the carb.

Second, I know there are options available to keep water from entering the tank via the tank vent.

Yes the vent can be relocated, but best method is secure the boat a better the next time and take your time.

Third, what should I do about the carb if water did in fact make it through the filter? I was cranking on the starter quite a bit trying to get out of barge traffic.

Remove the top of the carb and dry it out. With the fuel line disconnected, take a container and use the fuel pump to pump the water out until fuel is clear. Once clear, pump a bit more to verify, then replace the fuel filter, and run for a bit. After some time pull the filter and check for water. Reinstall, bring a spare filter and container if it needs to be change for the next few boating outings.

Last, do I have to waste the near full tank of gas? My gut and knowledge says yes, but does anyone else know a way to not waste so much gas?

No, you should be good, water is heavier the gas, but don't let it sit, get the water out. The gas will start to absorb the water. Maybe toss in a couple bottles of heat or other stuff.

Hey, this is the one time snake oil might be useful (seafoam)

 

[Rick Stephens]

++1 to AD's post. You need to be in a hurry with getting water out of gasoline that has ethanol blended in. Ethanol is incredibly hygroscopic. As soon as you got water in your tank your ethanol starting combining and starting the phase separation process. Water and ethanol are both polar. Each have electrical charges that attract the other. Gasoline is electrically neutral, non-polar, and won't hold the water in suspension due to electrical charge. As the ethanol electrically attracts the water, it binds with the water and falls out of suspension with the gasoline. Water mixed with ethanol is heavier than gasoline, so it drops to the bottom and is sucked into your carb. This is phase separated fuel. Phase separation by itself is only part of the problem, pulling the ethanol also drops the octane level of the gasoline that is floating on top. If you clean out the water and ethanol mix, the gas left over is too low of octane which will cause pinging, which is what damages your engine.

If you do pull a bunch of water off the bottom (which will be attached to your ethanol), and decide to run off the rest of the gas, fill up the next couple times with high octane premium. It will help prevent the low octane knock that comes from pulling the high octane ethanol out of the gas.

 

[smiles16]

Well I always use 93 octane in the boat (thus me wanting to save it), so I guess I'll be okay here. As far as using the fuel pump to drain the tank off, how do you do this with a mechanical pump? It's a late 80's Merc 120.

 

[alldodge]

Always using premium when 87 is all that's needed is just costing you more money but its your boat.

The pick up tube is on the bottom of the tank. Have the boat sit with the bow up a tad, just like it would in the water. Remove the purple 12V wire going to the coil. Then just crank it over a bit. With the line removed from the carb it should push fuel out. Crank for 20 to 30 seconds, then let cool down for a few minutes, and repeat. We don't want to over heat the starter

 

[Rick Stephens]

The ethanol carries 112 octane. It is a substantial part of you octane boost to 93. Depends on how much water to how low your octane gets. Some canned octane boosters are ethanol based and will just make the problem.worse. So take it careful when you burn the wet gas off.

 

[smiles16]

Thanks guys, pumping that water out this afternoon.

 

[Baylinerchuck]

++1 to AD's post. You need to be in a hurry with getting water out of gasoline that has ethanol blended in. Ethanol is incredibly hygroscopic. As soon as you got water in your tank your ethanol starting combining and starting the phase separation process. Water and ethanol are both polar. Each have electrical charges that attract the other. Gasoline is electrically neutral, non-polar, and won't hold the water in suspension due to electrical charge. As the ethanol electrically attracts the water, it binds with the water and falls out of suspension with the gasoline. Water mixed with ethanol is heavier than gasoline, so it drops to the bottom and is sucked into your carb. This is phase separated fuel. Phase separation by itself is only part of the problem, pulling the ethanol also drops the octane level of the gasoline that is floating on top. If you clean out the water and ethanol mix, the gas left over is too low of octane which will cause pinging, which is what damages your engine.

If you do pull a bunch of water off the bottom (which will be attached to your ethanol), and decide to run off the rest of the gas, fill up the next couple times with high octane premium. It will help prevent the low octane knock that comes from pulling the high octane ethanol out of the gas.

Great explanation of phase separation and ethanol octane. You would be hard pressed to find that explanation on the web. That paragraph or two should be a sticky IMO. Thank you.

 

[bruceb58]

Remove the fuel gauge sender and get a manual hand pump to pump all the water out at the bottom of the tank. The fuel pickup is usually not all the way at the bottom.

 

[smiles16]

Thanks guys. I pumped out about a gallon of gas through the fuel pump and then ran the engine. I drained the water separator and ran it. It's all good now!

 

[NHGuy]

No, it's not. Drain it all the way or you'll be having troubles later.

 

[smiles16]

I ran it near empty and filled 'er up with the good stuff.

 

[bruceb58]

There is still water below the fuel pickup. That is why you need to pull the fuel gauge sender and pump that way. The person who told you to use the fuel pump to do this gave you bad advice.

 

[smiles16]

Oh Okay, I'll get it done right this weekend

 

[alldodge]

As with all statements made by folks here it is their opinion and should be treated as such

 

[bruceb58]

There is going to be water below the pickup so your choice if you leave it there or not. Personally(yes my opinion), I would get all the water out.

Had a boat a long time ago that had some water below the pickup and we sucked it out through the fuel sender port.

 

[alldodge]

My opinion
The OP said he uses E0 fuel, he pump until the fuel was clean. What ever is left, if he adds some heat/seafoam (ethanol) to the gas, and/or uses E10 gas, the ethanol will absorb what ever water is left.

My post #2, Hey, this is the one time snake oil might be useful (seafoam)

Agree putting a tube down the sender hole will get more but note all will be removed unless drained and dried out.

 

[bruceb58]

If he is going to add anything to the gas, the last thing he want to use is ethanol. Isopropyl alcohol is what is needed in this case and that is what is in gas driers.

My Opinion
Tip the boat back, stick a pump in until it hits the back edge of the tank and pump out a gallon or two. Keep on pumping until you see no water. Depending on how far the pickup sits off the bottom determines how much water is in the tank, If the pickup sits far enough off that there is still a gallon of water in there, you are going to need so much gas drier that it is economically unfeasible.

Once you get as much out as you can with the pump through the sender hole, then add a can of gas drier that has Isopropyl alcohol in it to get the last few drops.

 

[smiles16]

I did add a bottle of the red heet just to be safe. Ran the boat for a few hours and only had about an ounce of water come out of the separator.

 

[bruceb58]

and only had about an ounce of water come out of the separator.

That's not good. You need to get the water out of the bottom of your tank.