Fuel filtration

FYI anyone looking to purchase in line fuel filters, with clear plastic body, gauze filter medium and 8mm in/out spigots ;

Baldwin BF 7863 

Baldwin BF 7850 - this one has about X4 the surface area of the above

Claimed filtration 75 micron (both)

Hengst H102 (straight) & 103 (elbow) WK

Claimed filtration 150 micron

Hi Sean,

We got away from plastic filters because if your fuel has ethanol it softens them.

"We got away from plastic filters because if your fuel has ethanol it softens them."

"Plastic" in this context is a generic term covering materials that look like but may not be the same.

I have used these Hengst Filters for about 11-15 years, in both diesel (my intro) & a range of petrol engines including Rotax 912 ULS.

I am almost certain these filters are supplied, as standard, with many European  factory built aircraft.

I have never had a problem but then I don't (knowingly) use ethanol fuels.

I can not imagine that a reputable company, like Hengst, would supply a filter that may be degraded by the fuel passing through it, nor the makers of a number of European light sport aircraft.

I recycle my used (Rotax) filters to my ground based engines - mainly mowers, pumps & a generator. A shot of carby cleaner followed by a good blast of air seems to restore, most if not all of, their efficacy.

The fact that the filters can do 100 hrs in a Rotax and then be recycled for many years of ground based engines usage, strongly suggests to me that the casing/body of these filters is impervious to the fuel passing within.

I may be moving to the Baldwin equivalent for my new aircraft as they seem to offer finer filtration and a much larger filter area (possibly x 6 ), while still having a clear "plastic" body for easy visually assessment.

Do you use auto fuel or 100LL? Does your auto fuel have ethanol and if so what is the percentage? We have up to 10% here and some states up to 15%

Roger Lee wrote:

Do you use auto fuel or 100LL? Does your auto fuel have ethanol and if so what is the percentage? We have up to 10% here and some states up to 15%

Never (almost) use 100LL (AvGas)

By law all of our (Australian) service (gas) stations must offer fuel with ethanol - we call it E10 (e10%). As the consumer, we are not obliged to use it and I don't.

Many in our light sport community believe that even fuel not listed with an ethanol content, may have some % so there is much discussion on how to check for ethanol.

Don't have first hand knowledge but believe petrol with ethanol has been widely available in Europe for many years, hence Rotax approving the use of up to 10% in its engines.

Note my comment about aircraft coming from Europe being supplied/fitted with Hengst H102 WK and/or H103 WK filters.

I very much doubt that these filters (available for sale all over the World) will be adversely effected by any level of ethanol in fuel.

If in doubt, fill a glass jar with E10 (or higher%), completely submerge a filter in the fuel. Check for softening/discoloration/crazing, every few months - I recon you will give up after 2 years or so.