water, water & more water in fuel

[Massimo]

Hi All,
Have an aquilla 582 and over december took it to our farm in the northern province (still there). On a lovely warm afternoon i experienced an engine out (thankfully just before take off!!!). Inspected and found water in fuel. Contacted old faithfull (Oom Hans) and he patiently guided me through process to restart motor. I then flew and after landing found MORE water and discolouration in fuel. Please note i did inspect fuel before take off and very minimal water found.

To date this is still happening, drain water before flying but still more water after flying, and im not talking about a few drops its more like a few 100ml! Does anybody know what could be the problem. Never had this when plane was at baps. Have sent sample of fuel to Total for analysis but am still awaiting there reply, but my neighbour who also has aquilla and buys same fuel does not have same problem.

Any ideas of what is causing this?

[taaipitperske]

Did you perhaps fly low over the neighbours wife while she was sunbathing

[Morph]

Damn good question,

Obviously it's coming from somewhere. Do you have a breather pipe or just the breather hole in the cap of the tank? Is the overflow bottle of the radiator not leaking into the tank, which could explain the discolouration.

What is the humidity like?

I know planes are more prone to getting water in the tanks with empty tanks rather than full. try to keep the tanks full.

[Massimo]

just have breather hole in cap, humidity similair to jhb.
Did attempt to keep tank full and water was less but after first flight checked and water had developed again.
will check radiator overflow, but i dont think its that.

Many seem to think thats its the fuel supply, guess ill have to wait for test results.

[Massimo]

nope under roof in hanger.
thing that bothers me is how can there be no or little water when tank is full and then immediately after a short flight there is lots of water.
will drain tank completely on next flight and re-fill with another supplier and see the results. Only in two weeks time sadly though.

[Mogas]

Ya this is interesting Freshman.
My only experience with lots of water in the fuel was in Zim back when the fuel manufacturers were still adding ethanol produced from sugarcane to petrol, producing the dreaded "blend" Not sure of the science behind it but this blend produced a lot of water in the fuel. Later on this blending was abandoned (no more cane farmers) and we directly imported normal petrol, end of water problems. Maybe your fuel came from a batch of some sort of ethanol/petrol blend.
Let us know how it goes.

[DieselFan]

This is really confusing, you saying you take off with 60l after removing small amounts of water, then land and have loads of water? You are sure this isn't a JetSki?

Seriously though

If fuel supply how does water form after a while? I would think Morph's suggestion makes most sense although why someone would route it that way...?

When did this happen? Don't know if linked but this last weekend due to the heatwave my mom in her car had jerking problems thought supply too ended up being fuel was too hot and also found water by filter coming back from Warmbaths (44C). Same day FIL came back from Richards bay (47C) had EXACT same symptoms with his Landy.

[Pumba]

Freshman

What Mogas is describing is what is the fact that alcohol is "hygroscopic". It means that it has an affinity for water. Any alcohol blended into petrol has the ability to absorb a certain amount of moisture from the air, or any other source.

Regulations in SA used to limit the amount of alcohol blended into fuel to no more than 12 %. (I do not know if this has since changed, I've been out of the country for a while.) The petrol companies produce ethanol alcohol as a by-product and blend it into the petrol they produce, unless they have a market for it elsewhere.

What you are describing here does not sound like this is your problem, its sounds like too much water. If the water was in the petrol when you bought it, it should settle out at the bottom of the tank (petrol is lighter than water and floats on top) after a while, and you should have been able to drain it all of. Remember, the little protrusion at the bottom of your Aquila's tank can only hold a small quantity. If the trike was not standing level when you first drained it off, you could have had some trapped in one of the far corners of the tank, and after churning it up and flying, it would settle at the lowest point again.

My number 1 suspect would the Filling Station you bought this fuel from. Drain some of it out into a clear glass container, and let it stand for a while. If there is any water, it will settle to the bottom. It is not uncommon to have water in the underground storage tanks at filling stations, there has been many accounts of it in the past. The fact that your neigbour did not get it after buying from the same supplier does not say too much. Did you buy at the same time, or share the same can of fuel?

Let your trike stand for a period of a few days, and drain any water out of the tank. I would strongly advise you to decant or siphon it all out of the tank. If you wish to get your value out of it, use it in your lawn mower (it won't hurt when that engine stops!)

If you have to put it back into your plane, pour it through a funnel with a chamois cloth draped into it. This should remove any small quantities of water that remains.

Ask Nic (Eagle1) about this. A few years ago he refueled his trike, and had an engine out on take of. Made a bad landing and had a huge dent in his pocket after that!

What DF is describing in his reply sounds like fuel vapourizing in the injection system in very hot conditions.

Good luck, and don't go fly until you've solved this.

Barry

[ZULU1]

Just remember that Synthetic oils are hydroscopic and will give some problems, I flew a lot in Mozambique where its a given that fuel has water..further north means more aqua additives..

When you fill the tank strain the fuel through a good quality chamois leather and this removes it at source. Strangely since I have changed to a 4 stroke (unleaded) and use unleaded from a busy garage, in two years I have had zero problems at all. But i get carb icing..

eish Zulu1

[Arnulf]

Hi Freshman,

look at the attitude of your Aquilla whilst it is on gthe ground, vs if airborne. If on the ground, the lowest part of the tank could be the front, ie. thats where the water collects. Airborne the lowest part is in the rear, ie. water collects in the water drain sump.

Regards,
Arnulf

[Massimo]

Morning All,
Thanks for all the advise, lots of info. I will work through it all and find the solution and let you all know.

Its a scary thought though that this can happen, when i had that engine out it really hit home as to the reality of knowng what to do in the air.

[Robin Hood]

A question: If you use a chamois to filter your premixed fuel/2 stroke oil, would the chamois not also filter out some of the oil and lead to lubrication problems?

[ZULU1]

No sir, filter between jerry cans with ground crew before filling plane, then add oil..never had a problem but a half a tee cup of water per 20 litres is the norm...only used ordinary ( SA made) mineral oil though..however my crank went at 180 hrs from new when returned..582. Second time at 380hrs..pre mixed..

eina Zulu1

[Massimo]

Morning All,

Well the verbal report back from Total is that they found large quantities of water in our petrol sample, but when they tested their supplier they found no water (what a surprise)!!
Anyhow still waiting for the written report, but in the meant time i will buy from another supplier and see what happens to the water issue. Keep you posted.

[Perry]

Freshman,

I found a neat method to check petrol for water at the fuel station. Take an old glass jar (BlackCat Peanut Butter Jar) and mark a level on the side with a marker pen.

Fill the jar till the marker with water.

Then add a sample of the fuel to the water and mix gently. If the fuel has water, the water in the fuel will separate and mix with the existing water and Viola the water will rise above the mark! You can use this to rapidly check for water before you purchase any more fuel.

On another note, ethanol was mentioned. Ethanol is exceptionally hygroscopic, in other words it attracts heaps of moisture. Fuels without a blend of ethanol in them are becoming harder to find as many petrol companies are being regulated to add blends as they are produced from renewable substances like mielies (corn) and sugar cane - this is providing affordable blends and meeting environmental considerations. These fuels require careful handling, however, moisture is almost unavoidable and managing removal of water is more of an issue as well as a major consideration.

Strangely enough, Brazilian Aviators have performed a fully certified conversion on Lycoming Engines in the interests of powering ag machines on pure ethanol! Apart from the advances in electronic ignition in aviation engines, alternative fuel management solutions will surely be an area for innovation.

Regards