Real gasoline, E-10, Water separator, Star-Tron?

[Airwaves]

My question involves all 4!

Quick background. When I launched my "southern" boat (Mass) this year I discovered that despite my best efforts, E-10 attracted enough water to make my engine nearly inoperable. (1990, 115 HP Mercury Outboard) I added Star-Tron to the full tank of gas and it allowed the engine to run although the power was significantly reduced.

Yes the engine was tuned and adjusted this spring, etc. I was told that adding a water separator to the fuel system would deal with the problem of water in the tank that is attracted by E-10.

There you have it. Now, a couple of questions for folks who have already done this.

I installed a water separator between the fuel tank and the engine today, what can I realistically expect the separator to do? Will it make it seem that I have 100% real gasoline or are my expectations too high?

I have been told not to "mix" real gas with E-10, is that a recomendation aimed at folks who exclusively use real gas, like at Winnipesaukee, or is there another issue at work here?

I was told when I bought the water separator kit that if I put an additive like Star-Tron into my fuel I should change the separator filter after the fuel with the Star-Tron has been used, but no one has told me why.

I am set to hook up my system tomorrow. I want to replace the fuel line from the tank to the separator and engine. Then I will refuel the boat.

Here's hoping!

[jrc]

First of all E-10 gets blammed for everything. It does cause real problems, just not as many as you hear about. Of course if your boat gets the problem...

It will combine with water already in your tank and if there's enough water it will fall out of solution with the gas. This puts a water and ethanol blend in the bottom of your tank that won't burn and it also leaves the gas with a lower octane.

Your water seperator should pull out the water but it won't restore the octane. So you should be able to run but you may have octane issues like pinging. Does Star-tron add octane?

Ethanol also cleans your tank and fuel system. This sounds good but the dirt and varnish from years of normal use will now dissolve. This dissolved crap can clog fuel filters and the filter in your seperator. That's probably why they tell you change the filters. Star-tron is going to try and keep the gas, ethanol and water all together so you can burn it, but that means it has to get through your filter.

I don't know why you can't mix E-10 and normal gas.

[kchace]

Does your fuel/water seperator have a clear bottom bowl? If it does, check it frequently. If you find water in there, you can drain it off. If it does not have a clear bottom bowl, you should probably dump out the filter after the first couple of trips to see what its collecting. Keep in mind that a fuel/water separating filter can only hold so much water! If it gets full of water, the water will start going out to your motor. So it does need to be checked now and then. After a while, you'll get a feel for how much of a problem you have and what else you might need to do.

As far as changing the filter is concerned - on an older system where you just started to use E10, you never really know how long you can go before the filter needs to be changed. If I were in your position, I'd carry a spare filter on the boat and change it only if it starts to get clogged or at the end of the season. It may be ok for a long while and it may not.

I mix E10 and the non-E10 lake gas all the time with no issue and I have read statements from oil companies that mixing MTBE and E10 is not a problem. (If it was, I would think all the cars would have problems too)

Ken

[Airwaves]

Thanks, I'll let you know what happens. My fuel filter and water separators don't have clear bowls so I'll have to wait until the engine starts to bog or miss before I know it's time I guess.
Thanks again

[bigdog]

Would appreciate people's opinions on a recent engine problem
I experienced…..

Labor Day, I decided to take my boat out on a nearby lake. I always start my boat in the driveway and let run a few minutes, then shut down. I always do this before heading for the boat ramp, so I won't have any problems or surprises after launching.

Launched the boat without issues, motor started immediately. After about 20 minutes on the water and about 2 miles down the lake, the engine started coughing and spitting, and finally stalled out. I made several attempts, to start the engine, but the same continued.

Figuring I may have some bad gas, water in the gas, or a clogged fuel filter, I was able to start the engine and limp into the nearest marina, and added fresh gas in the tank. Unfortunately, they didn’t have any ‘dry gas additive’.

I then decided to head back to the boat ramp. This took over an hour to travel the 2 miles,and only able to drive at ‘no wake’ speed. During this time the engine must have stalled a dozen times, but we finally arrived at the boat ramp. I’m thankful we didn’t need to be towed ! Needles to say, our boating day ended, shortly after it began. Not a good way to end the Labor Day weekend!

During this entire season, I haven’ had any engine issues. Last time I had the boat on the water was about 3 weeks ago, since then it’s been sitting on it’s trailer in the yard. FYI, engine is a 1995 Mercruiser 4.3 liter.

Could this be a E-10 issue, fuel filter, or some other unrelated issue ?
Would appreciate everyone’s feedback.

Thanks!

[Dave R]

The ethanol in E10 is "dry gas". No need to add more, 10% is a huge amount and it can absorb a huge amount of water.

Bigdog, Fuel delivery would be the first thing I'd look at. Clogged fuel filter (there are likely two on your engine, a big one that looks like an oil filter and a smaller one in the carb), collapsed fuel line, failed fuel pump, pinched tank vent line, or failed or clogged fuel pickup in the tank could cause the symptoms you described.

[ITD]

Big Dog,

Try running it until it stalls, then loosen the gas cap. If you hear a whooshing sound then the gas vent is clogged and the engine should start right back up.

[Kamper]

I remember when this stuff came out last year. If you do a search you'll probably get a dozen explanations here and on any of the larger audience boat forums like "the Hull Truth" or "Salt Water Fisherman." Some manufacturers' sites, and fuel companies' sites, carried explanations also.

My memory isnt too sharp on this because it doesnt effect me any more but I believe if you mix the two together the side-effects can be worse if you let the mix sit unused for any length of time. It was advised that you should run your tank as low as practical before filling with the other and then run it as long as possible. There may have been other negative interactions between the ethanol and MBTE but I cant rember what they are.

Running the motor will allow the disolved varnish to run through the system without settling and re-solidifying in awkward places and block the fuel stream. Some of the deposits may come off in particles or snotty lumps and clog your filter if they dont disolve enough to pass through, for that reason you should carry a spare filter or two.

After you've run for a while on E-10, and gotten past that risk period, your system will be clean and you can switch back and forth if you have to but it's best not to let the non E-10 fuel sit in your tank or you may start the cycle over again.

Ethanol can disolve some of the materials in fiber-glass. If your tanks are suscepttible you'd probably know it by now because those materials would have settled in those awkward places and your motor would probably be unusable by now. It's still not a bad idea to check with your mechanic to see if there's a coating that can be applied to glass tanks to protect them. I have no first-hand info on this since I use portables.

This is not the "Gospel" on E-10 but should give you a sense of the situation.

Goodluck!