Poor Man's Gascolator & Safety
Wire Hose Clamps
Water in the fuel is a problem to all
aviators, not just Kolbers. An aircraft gascolator, mounting bracket
and drain valve will set you back at least $74 plus shipping.
Here is a cheaper alternative. Observe one each $1.99 Deutsch
FF422 filter procured from the local Autozone, but similar automotive
filters would also work equally well. This one is fairly small,
it looks like it would hold just about two Bing float bowls worth
of water. Bigger ones are available.
Drill, bore, or grind a hole in the bottom big enough
to fit the rubber grommet, and then grub out all the guts from
inside the filter, normally including a metal filter bottom, a
bunch of paper and some glue, get rid of it all. When you get
done, you have a water trap and a water drain, not a filter. You
still need your normal filter between the gascolator and the engine.
You will end up with something like this: an open
nylon water trap cavity with an inlet, an outlet, and an open
place where all the paper filter stuff used to be. A 3/16"
masonary drill bit in a slow speed drill, followed by some chiseling
with a long screwdriver routed out the last of the filter retaining
glue. The filter cap metal was thin, needle nose pliers and the
metal snips persuaded it to come out of the hole.
Here are all the components laid out and ready to
assemble, and then the finished product. Obviously the last 3/8"
of water in the bowl will not go down the drain pipe, which is
why some folks might rather pay more for the STC'd version: it
drains all the water out.
Depending on where your gascolator is, you may need
to plumb it to a drain at the fuselage bottom, this is my solution:
Melted a hole in the Stits, soldered a homemade
copper flange to the 1/4" copper tubing on the top side of
the fabric, and then just riveted it to the fabric with some nylon
washers on the outside of the fabric.
All parts but the filter
available from Aircraft Spruce, the Elbow is part #FTEB01@$1.95,
the rubber grommet is part # FTB01@$.99, and the Curtis drain
valve is part # CCA-1550@ $8.95. Total? $11.88 plus shipping.
Using eurethane tubing? Tired of
leaks? Read on
Once you start plumbing all the fittings and connections
on a Kolb, expecially one with two gas tanks, an auxiliary fuel
pump, two carbs, etc, you will need a potfull of little hose clamps,
and you will then discover that metal ones will leak, & nylon
ones will get brittle after a few years. Wouldn't it be nice to
get hose clamps almost free, that will not leak? It's possible,
it's easy, it's good old safety wire.
Warning! This will
not work with vinyl or plastic fuel line, the wire will cut through
the tubing. It will not work
with typical rubber automotive fuel line, use metal hose clamps
This method works with .032 stainless safety wire
and blue or clear eurethane fuel line, or yellow Tygon fuel line.
I have never tried it with different sizes of wire, it is possible
that smaller or bigger wire may cut through the eurethane, who
After you have the tubing in place, wrap the safety
wire around the tubing twice, laying it down flat and even. The
wrappings should not overlap each other, the picture on the left
sort of makes it look like the wire over laps itself, but it doesn't.
You want the wire wrappings to lay alongside each other, and only
overlap at the twist.
Then go ahead and spin the wire snug with the safety
wire pliers, it doesn't have to have a death grip, it just needs
to be tight enough not to leak, move, twist, or come off. Try
and twist the tubing; if it won't twist or move, that's tight
enough. Now trim the spun end to about 5/8" long. Take your
needle noses and bend the end over out of the way towards the
tubing's open end*, lest you run your finger or hand past it later
on, cut the fool out of yourself, and then get blood stains on
your nice shiny airplane. (Guess how I know this?) You now have
a simple, expendable clamp that grips for the whole circumference
of the tube, and costs less than a penny. With a little practice,
you can make all of them look identical...
(*If the sharp end pokes the tubing, you want it
poked somewhere harmless)
not all eurethane tubing is equal, we are not using STC'd stuff
here, so just in case you get something inferior, you should practice
making a few of these at the workbench, and spin the wire down
excessively tight until it breaks. Then examine the tubing. There
should be two slight dents in the eurethane tubing, but nothing
more. If it looks at all like the wire is digging in too deep,
scrap the idea, something is bogus, because normally the wire
breaks long before the eurethane tubing even begins to yield.
If it looks like the wire is cutting through, then you might even
want to question that particular batch of tubing, because it shouldn't
be happening. Make several practice runs, know what you're doing,
develop a feel for what is enough, what is proper, and what is
This method is cheap enough, simple enough, and
quick enough that you have no excuse not to.
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