Microlight fuel testing

[Jan Olieslagers]

My microlight has a header tank at the lowest point of the fuel circuit, with a drain valve under it. Up till now, I have tested for water by draining from here into a clear plastic cup. Now I came across the below tester, which claims the ability to indicate the alcohol content in the fuel. Would it be worth its 15 euro's? Or is my current "procedure" sufficient?

http://commerce.ciel.com/ulmtechnologie/upload/items/default/70251.png
(article #70251 at ULM TECHNOLOGIE - Aéroparts - Aéroshop - Accueil / Home (http://www.ulmtechnologie.com))

[Heston]

I think there are two separate issues here.
Firstly your drain test is standard practice for checking to see if there is water as discrete drops or larger amounts gathered at the bottom of the fuel system. This mostly arises from condensation in the tank. If there is water then you should drain it out until there is no more when tested.
Secondly - the alcohol tester is to detect batches of motor gasolene that have had alcohol (ethanol) added by the fuel supplier. This is becoming increasingly common, in the UK at least. Wise people state that alcohol in the fuel is not a problem for the engine itself, but that it attacks rubber parts of the fuel system and the tank linings which can lead to debris in the fuel system, blocked jets and filters and so on. I am not an expert, so I am happy for others to tell me I've got this wrong, but its what I think is the current position.
I don't think any of this applies to Avgas.

By the way its not called a "header" tank if its at the bottom of the fuel system. A header tank is at the top, as the name suggests (like the expansion tank in a car's coolant system). But we know what you mean :)

H

[Heston]

Your link to the ULM Technologie website goes to what looks to me like a standard fuel tester, so not sure how this detects alcohol in the fuel. I think you need a chemical based test to do that.
Fuel-Testers E10 Gas Precautions & Tips + Ethanol Fuel Test Kits to protect your engines from alcohol-caused damage. (http://www.fuel-testers.com/)
for example

H

[avturboy]

Possibly more appropriate to call it a sump rather than a header tank ... sump at the bottom, header at the top.

Fuel sample for water separation is taken from a sump because gravity causes water to separate out and fall the bottom (being more dense). Checking the alcohol content is a chemical check of the fuel make up and can be taken from anywhere in the system (other than the sump if it does contain water)

[Rod1]

In the UK micros are allowed to use fuel with Ethanol (E5 or E10). If you are happy that your engine and fuel system can cope – many can – no need to test.

Rod1

[Maoraigh1]

I've seen a drain tester with additional markings for doing the CAA suggested alcohol in fuel test (using water). You could easily add markings to your water-in-tank tester.