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Another option is:
http://www.weldonracing.com/product/25/EFI_and_Carbureted_Filter_Assembly.html
From: Lancair Mailing List [mailto:lml@lancaironline.net]
On Behalf Of Bill Bradburry
Sent: Monday, July 28, 2014 11:16 AM
To: Lancair Mailing List
Subject: [LML] Re: FW: [LML] Re: Gascolators and fuel lines.
Mark,
I would not recommend this type of filter for an airplane.
I couldn’t find a part number for the replacement filter media for this filter. The filter part number itself is different depending on whether you want cellulose
at 10 microns or steel at 100 microns. I bought a similar diameter filter that was three and a half inches long and the filter media was a round flat screen that the fuel flowed through. The filter media was about three quarters, seven eighths inch in diameter
and would take nothing to plug it up completely, which it did after about an hour of running. It was a black sludgey material that I think came from my incomplete cleaning of the fuel hoses that I made up after cutting to length and installing the hose ends.
Anyway after I saw how easily they were to plug, I got rid of them and installed a fuel filter of the style of an oil filter. They have a lot of filter media and will plug very slowly so you should be able to see your pressure or flow dropping for quite some
time before you would lose the engine.
I am not recommending this particular filter, but it is of the type I would recommend.
http://www.summitracing.com/parts/sum-g1507/overview/
Bill
From: Lancair Mailing List [mailto:lml@lancaironline.net]
On Behalf Of Mark Sletten
Sent: Monday, July 28, 2014 4:42 AM
To: Lancair Mailing List
Subject: [LML] Re: FW: [LML] Re: Gascolators and fuel lines.
Gang,
The vast majority of answers on this subject have focused on the filtration benefits of the gascolator. I think Dennis Johnson's observations are spot on. If one carefully sumps the tanks (ensuring the aircraft is sitting on a level surface)
prior to engine start it would be nigh impossible to get a coherent slug of water large enough and to interfere significantly with engine operation. This is especially true for fuel injected Continental installations, where a significant portion of the fuel
pumped to the engine is unused and returned to the tank. Is it possible for a very large slug of water to remain coherent in five gallons of fuel while agitated by aircraft motion and fuel recirculation? I suppose it is, but it seems unlikely to me.
That aside, no one has mentioned ever finding water in the gascolator of their Lancair. Which makes sense, because in order to do so water would have flow uphill while on the ground, or remain separated enough from the fuel to fall out
while flowing thru the gascolator at something approaching a half-a-gallon per minute while the engine is running.
Regarding the filtration capabilities of the gascolator; I've emailed Andair for more information on the specifications (filtration level, filter material area, max fuel flow, etc.), but they have yet to respond. If anyone has this information
I would greatly appreciate it.
Kevin Stallard suggested the gascolator would appear to be a better option as a filter than an inline style. The type of inline filter I'm talking about is not your prototypical one-inch diameter, one-inch long plastic see-thru filter we've
all seen on our lawnmowers. I talking about something more like this:
This filter is 1.75" in diameter and 6.25" long. If the filtration media was a simple cylinder that size would yield 30+ square inches of filtration area. Since the media is pleated (much like your typical oil filter), the filtration area
is actually much larger. Maximum flow rate is 150 gph, which is more than three times that required for an IO-550. That suggests this filter could be two-thirds clogged with crud and still have adequate fuel flow. And let's not forget there would be one filter
for each tank; if one clogs I can still switch tanks.
Additionally, this isn't a throw-one-in-and-hope-it-works scenario. These filters would be installed in a location making it exceptionally easy to remove for inspection/servicing--something that would occur following every engine run up
to first flight. My reasoning is that such a test regimen will reveal any problems of the type mentioned here.
On Thu, Jul 24, 2014 at 4:39 PM, John B <2thman1@gmail.com> wrote:
Like most of you who responded I would not give up the gascolator. Have done two annuals since flying and both times have found almost a teaspoon of white fuzzy stuff. Fiberglass particles I'm virtually certain, and I thought I had done
a perfect job of cleaning out the tanks before first flight.
Adam,
My experience is the same as yours. I often found/drained water out of my old Cherokee tanks, and MANY rental airplanes as well. All were parked outside, and I think avgas came with a certain amount of “water added” in the old days…
L
I’ve never found any water in the gascolator of my IV-P, so the fuel doesn’t have/collect any water…or
it’s going through the engine and being vaporized--which I think unlikely. I know the gas caps are MUCH better than the old Cherokee “stoppers,” and I rarely park the Lancair outside these days.
Like you, I was meticulous in cleaning/keeping the fuel tanks/lines clean during fabrication and
through flight test. I still collected some small amounts of carbon fuzz, and a few bits of aluminum in the gascolator during testing, and at the first two condition inspections. Almost undetectable bits of something for the last three, not enough to even
identify when poured onto a piece of white paper… So the gascolator/filter is probably not serving a useful function today…but deleting it would be like throwing away the spare tire in my car, IMHO… I carry a few critical spare parts in my airplane for the
same reason…
Bob
From: Lancair Mailing List [mailto:lml@lancaironline.net]
On Behalf Of Adam Molny
Sent: Thursday, July 24, 2014 1:30 PM
To: Lancair Mailing List
Subject: [LML] Re: Gascolators and fuel lines.
Hi Mark –
Our planes are kept in a heated hangar so there’s no opportunity for water in the system from rain or
condensation. Back when I was renting Cessnas and Pipers I did occasionally drain water from the gascolator. Those planes were kept outside.
The lowest point in the Legacy fuel system is the fuel selector valve, but it’s not designed to capture
water or sediment like a gascolator. Your notion that the fuel flows too fast for water to settle out is difficult to prove or disprove. I always envisioned tiny globs of water flowing out of the fuel tanks and coalescing into a large glob of water in the
gascolator. The real test would be to pour a cup of water into one wing tank, run the engine at high power, and see where the water ends up (in the gascolator, out the tailpipe, or back to the fuel tank). However, deliberately adding water to the fuel system
seems like a bad idea so I’m not going to try it.
I think you are saying you want fuel filtration but there’s no point in having water separation since
a gascolator won’t work. Can you be 100% certain that you will never get water in your system? What about flying through rain with a loose fuel cap? What about being parked outside at Oshkosh for a week? If you do get water in the system, where will it go?
I hate to fall back on the “It’s always been done that way” argument, but gascolators exist for a reason.
For all the Legacy drivers out there: Have any of you ever discovered water in the gascolator?
Good discussion!
From: Mark Sletten [mailto:mwsletten@gmail.com]
Sent: Thursday, July 24, 2014 9:15 AM
To: Adam Molny
Subject: Re: Gascolators and fuel lines.
Adam,
I wasn't questioning the value of fuel filtration, just whether a gascolator is the best choice. As I understand it, the gascolator provides a means to filter the fuel and a low
point to catch water that may have gotten into the fuel system. There are several arguments against using one for the Legacy.
-
In the Legacy the gascolator is not the lowest point in the fuel delivery path from the tank to the engine, so water in the tank should not flow to the gascolator before turning on the pumps. (I believe the same is true of the RV. Has your wife ever drained
any water from her gascolator?)
-
Given the high fuel flow rate and recirculation of unused fuel to the tank, it's unlikely the gascolator will remove any water with the engine running.
-
The gascolator in the engine compartment provides a large surface area to add heat to the fuel which can contribute to vapor lock. Lancair combats this with a heat shroud and blast air, adding weight and complexity.
-
The gascolator requires numerous fittings and breaks in the fuel lines, adding to complexity, weight and the possibility of fuel leaks.
Since the gascolator appears to be rather useless at removing water, it's primary function for the Legacy is filtration. With so many other filtration options available, it seems
illogical to put a gascolator in the engine compartment.
On Thu, Jul 24, 2014 at 7:12 AM, Adam Molny <Adam@validationpartners.com> wrote:
Mark –
The gascolator provides a large reservoir for capturing water and sediment. It also contains a fine screen
with a fairly large area that acts the final filtration element to keep junk out of your carburetor or injector(s).
Case in point: my wife’s RV6-A started showing small amounts of debris when sumping the fuel tank drains
and gascolator. We opened up the gascolator and found a small amount of debris at the bottom of the bowl, and the screen was about 5% blocked. There was no immediate danger, since the bowl would have to completely fill with debris and the screen would have
to be 100% blocked in order to kill the engine. It turned out to be bits of fuel tank sealant flaking off.
My point here is that the gascolator acts as a buffer and gives you lots of warning and lots of time to
head off any potential fuel contamination problem.
What is the argument for omitting the gascolator on fuel injected engines?
-Adam Molny
Legacy N181AM 255hrs
From: Mark Sletten [mailto:mwsletten@gmail.com]
Sent: Wednesday, July 23, 2014 7:35 AM
Subject: Gascolators and fuel lines.
Gang,
First: Gascolators. There is a great deal of debate around the web on the benefits of a gascolator in fuel injected systems. What's the consensus among Lancairians?
Second: I'm considering making my own engine compartment fuel lines. I plan to build them up from scratch including the fire sleeve (or not if the hose is sufficiently fire resistant).
Anyone have a recommendation on the type of hose to use?
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