[rebel-builders] Fuel slector valves

[Ken]

I too am a believer in a header tank. Solves the problem of air bubbles
when low on fuel, in turbulence, or sideslipping. I put a float switch
in the header tank to tell me if it is not full. I do find that I have
started to keep more fuel in the right tank for balance. An aileron trim
would probably be a better solution for me.

However when optimizing range or performance, one usually likes all
remaining fuel in one tank with an accurate quantity gauge so you have
confidence in how much is really there. Sometimes that avoids an extra
fuel stop for me. Kind of pointless having large tanks and carrying
extra fuel weight if you don't have confidence in how much is useable.
I don't like guessing and my Rebel performs noticeably better when I do
not carry excessive fuel. I have over 8 hours of fuel with full tanks.
In machines with multiple fuel tanks, it is not uncommon to watch a fuel
pressure gauge for fluctuations and then switch tanks before the engine
coughs. An amusing incidence of this (not in a Rebel) was accompanied by
a major aircraft pitch up which quite surprised me. What happened was
that when the engine coughed a group of parachuters all immediately
moved to the rear door to get out... Imagine trusting silk more than an
aircraft just because of a momentary hiccup ;)

I also recall an interesting night ferry trip on a newly purchased
aircraft. The destination had a curfew and the new owner was quite
nervous. It took me awhile to realize that he had previously rented
aircraft and had never actually flown with tanks less than half full.

I suspect that some specific Rebels may push air through the lines and
vent it through the carb float bowel. But many do not. One fellow used
transparent lines to prove that on his machine the air was being trapped
at the top of the vertical line. The air would not travel the last few
inches of horizontal tube back into the wing tank. Air in the line does
restrict fuel flow. He constructed a vapor separator at the top of the
vertical tubing to vent that air bubble. Fortunately when an engine
coughs, the first thing most pilots do is to switch on a tank that they
are sure has fuel in it which I think avoids the problem being discussed
below. With a header tank, I never give any of this a second thought.

Ken


Kevin & Nancy Mayville wrote:

I am going to jump in here because I don't understand why any one needs to
drain one tank completely, I can understand burning one tank down to say 3/4
or so for balance, I would never run a tank down until the engine coughs !
I run both my tanks at the same time and I don't have any balance problems
with or without a passenger.

My fuel system is a little different I have a ball valve at each aft wing
root ( which I can reach ) and then each tank flows in to a small tank like
a header tank ( aprox 2''x3'' x 16'' long mounted vertically ) aft of the
pilots seat. then the main shut off valve is just forward of the pilots door
.

This header tank eliminates any chance of air being trapped in the fuel
line. I believe this was the fix for the first generation of Glass Stars
because the fuel sloshed in the tanks and allowed air to block the fuel
lines like Walter stated, which caused some unscheduled landing .

Kevin C-FRFP


----- Original Message -----
From: "Walter Klatt" <Walter.Klatt@shaw.ca>
To: <rebel-builders@dcsol.com>
Sent: Tuesday, December 22, 2009 6:34 PM
Subject: RE: [rebel-builders] Fuel slector valves

I am quite sure it will happen to any tank valve top mounted gravity feed
set up in a Rebel or Elite. I have my tanks cross vented, plus a snorkel
vent on each cap.

It has to do with trapped air in the lines below the valves. The fuel is
trying to flow down, while the air is trying to vent upwards to the tanks,
which slows the fuel flow enough to stall the engine.

Think about it. When you shut one tank off run to run the other one dry,
all
the fuel will run out of both lines when the empty one finally drains.
When
the engine runs out of fuel, there will be nothing but air left in both
lines right up to the valves. Then if you close the empty tank valve, you
trap the air there. When you open the full one, the flow has to fight the
air coming up.

If you keep the empty one open, the air has a place to get pushed out and
vented, and no problem.

Again, if you use the right sequence, with opening and closing the valves,
everything is fine. But with the wrong sequence, your engine will quit,
and
you will not get it started in time before you hit the ground, guaranteed.

Trust me, I have been there, and I know this issue very, very well. And I
can replicate it on my plane on the ground any time, and I am sure I could
do it to yours if you have the same set up.

Walter

-----Original Message-----
From: mike.davis@dcsol.com [mailto:mike.davis@dcsol.com] On Behalf Of Ron
Shannon
Sent: December 22, 2009 3:04 PM
To: rebel-builders@dcsol.com
Subject: Re: [rebel-builders] Fuel slector valves

I believe the tank venting design will have an influence on this switching
procedure. Not to reopen a subject that's been covered quite a bit (see
archives) I think with dual vents and full cross vent (and perhaps other
configurations) it may be possible to run one tank dry before switching as
Drew suggests -- if you're so inclined. Personally, I wouldn't
intentionally
cause an in flight shutdown except in an emergency scenario where fuel
reserves absolutely had to be managed that tightly. Your mileage may
vary --
literally. :-)

Ron
254R


On Tue, Dec 22, 2009 at 2:41 PM, Drew Dalgleish
<drewjan@cabletv.on.ca>wrote:

Hi Walter I wonder if that problem could be unique to your plane cuz I
often run the pilots side tank empty to help balance my plane and get
maximum range. I think I usually turn off the empty tank before turning
on
the one with fuel in it and I've never expreienced any delay in the
engine
restarting.
As for floor mounted valves consider where you place it so that if you

ever

install floats you will be able to easily crawl through to the other side
for docking, pumping out, refueling etc.

At 11:27 AM 22/12/2009 -0800, you wrote: running one tank dry while flying. The sequence for closing and opening

the

valves is very critical to avoid an air lock. I know this from first hand
experience and am able to replicate the issue on the ground. run one tank dry, with the other full tank closed, you must first open
the
full tank before you close the dry one. Otherwise, your engine will quit,
and you will not be able to keep it running. It will restart, but then

keep

quitting on you.

the

full one can't flow fast enough. It flows just enough to start your

engine,

but it will keep quitting on you. If you keep the empty one open, the
locked air will vent up through it, and allow the good tank to feed down

to

the carb. Once it is feeding OK, and the air is out, then you can close

the

empty one. the ground when I first did it. locked in the lines above to the tanks. Drew

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[kpierson]

Ken:

You said that you have over 8 hr. of fuel, Do you have an extra
fuel tank? If so where do you have it? Or is it the header tank
that gives you the extra range? If so how big is it and where is
it? Or is your engine just that economical? I know, I know it's a
lot of questions!

Thank you

Keith P. 318R




On 12/23/2009 7:35 PM, klehman@albedo.net wrote to rebel-builders:

-> I too am a believer in a header tank. Solves the problem of air bubbles
-> when low on fuel, in turbulence, or sideslipping. I put a float switch
-> in the header tank to tell me if it is not full. I do find that I have
-> started to keep more fuel in the right tank for balance. An aileron trim
-> would probably be a better solution for me.
->
-> However when optimizing range or performance, one usually likes all
-> remaining fuel in one tank with an accurate quantity gauge so you have
-> confidence in how much is really there. Sometimes that avoids an extra
-> fuel stop for me. Kind of pointless having large tanks and carrying
-> extra fuel weight if you don't have confidence in how much is useable.
-> I don't like guessing and my Rebel performs noticeably better when I do
-> not carry excessive fuel. I have over 8 hours of fuel with full tanks.
-> In machines with multiple fuel tanks, it is not uncommon to watch a fuel
-> pressure gauge for fluctuations and then switch tanks before the engine
-> coughs. An amusing incidence of this (not in a Rebel) was accompanied by
-> a major aircraft pitch up which quite surprised me. What happened was
-> that when the engine coughed a group of parachuters all immediately
-> moved to the rear door to get out... Imagine trusting silk more than an
-> aircraft just because of a momentary hiccup ;)
->
-> I also recall an interesting night ferry trip on a newly purchased
-> aircraft. The destination had a curfew and the new owner was quite
-> nervous. It took me awhile to realize that he had previously rented
-> aircraft and had never actually flown with tanks less than half full.
->
-> I suspect that some specific Rebels may push air through the lines and
-> vent it through the carb float bowel. But many do not. One fellow used
-> transparent lines to prove that on his machine the air was being trapped
-> at the top of the vertical line. The air would not travel the last few
-> inches of horizontal tube back into the wing tank. Air in the line does
-> restrict fuel flow. He constructed a vapor separator at the top of the
-> vertical tubing to vent that air bubble. Fortunately when an engine
-> coughs, the first thing most pilots do is to switch on a tank that they
-> are sure has fuel in it which I think avoids the problem being discussed
-> below. With a header tank, I never give any of this a second thought.
->
-> Ken
->
->
-> Kevin & Nancy Mayville wrote:
-> > I am going to jump in here because I don't understand why any one
needs to
-> > drain one tank completely, I can understand burning one tank down to
say 3/4
-> > or so for balance, I would never run a tank down until the engine
coughs !
-> > I run both my tanks at the same time and I don't have any balance
problems
-> > with or without a passenger.
-> >
-> > My fuel system is a little different I have a ball valve at each aft wing
-> > root ( which I can reach ) and then each tank flows in to a small tank
like
-> > a header tank ( aprox 2''x3'' x 16'' long mounted vertically ) aft of the
-> > pilots seat. then the main shut off valve is just forward of the pilots
door
-> > .
-> >
-> > This header tank eliminates any chance of air being trapped in the fuel
-> > line. I believe this was the fix for the first generation of Glass Stars
-> > because the fuel sloshed in the tanks and allowed air to block the fuel
-> > lines like Walter stated, which caused some unscheduled landing .
-> >
-> > Kevin C-FRFP
-> >
-> >
-> > ----- Original Message -----
-> > From: "Walter Klatt" <Walter.Klatt@shaw.ca>
-> > To: <rebel-builders@dcsol.com>
-> > Sent: Tuesday, December 22, 2009 6:34 PM
-> > Subject: RE: [rebel-builders] Fuel slector valves
-> >
-> >
-> >> I am quite sure it will happen to any tank valve top mounted gravity
feed
-> >> set up in a Rebel or Elite. I have my tanks cross vented, plus a snorkel
-> >> vent on each cap.
-> >>
-> >> It has to do with trapped air in the lines below the valves. The fuel is
-> >> trying to flow down, while the air is trying to vent upwards to the
tanks,
-> >> which slows the fuel flow enough to stall the engine.
-> >>
-> >> Think about it. When you shut one tank off run to run the other one
dry,
-> >> all
-> >> the fuel will run out of both lines when the empty one finally drains.
-> >> When
-> >> the engine runs out of fuel, there will be nothing but air left in both
-> >> lines right up to the valves. Then if you close the empty tank valve,
you
-> >> trap the air there. When you open the full one, the flow has to fight the
-> >> air coming up.
-> >>
-> >> If you keep the empty one open, the air has a place to get pushed out
and
-> >> vented, and no problem.
-> >>
-> >> Again, if you use the right sequence, with opening and closing the
valves,
-> >> everything is fine. But with the wrong sequence, your engine will quit,
-> >> and
-> >> you will not get it started in time before you hit the ground,
guaranteed.
-> >>
-> >> Trust me, I have been there, and I know this issue very, very well. And
I
-> >> can replicate it on my plane on the ground any time, and I am sure I
could
-> >> do it to yours if you have the same set up.
-> >>
-> >> Walter
-> >>
-> >> -----Original Message-----
-> >> From: mike.davis@dcsol.com [mailto:mike.davis@dcsol.com] On Behalf
Of Ron
-> >> Shannon
-> >> Sent: December 22, 2009 3:04 PM
-> >> To: rebel-builders@dcsol.com
-> >> Subject: Re: [rebel-builders] Fuel slector valves
-> >>
-> >> I believe the tank venting design will have an influence on this
switching
-> >> procedure. Not to reopen a subject that's been covered quite a bit (see
-> >> archives) I think with dual vents and full cross vent (and perhaps other
-> >> configurations) it may be possible to run one tank dry before switching
as
-> >> Drew suggests -- if you're so inclined. Personally, I wouldn't
-> >> intentionally
-> >> cause an in flight shutdown except in an emergency scenario where fuel
-> >> reserves absolutely had to be managed that tightly. Your mileage may
-> >> vary --
-> >> literally. :-)
-> >>
-> >> Ron
-> >> 254R
-> >>
-> >>
-> >> On Tue, Dec 22, 2009 at 2:41 PM, Drew Dalgleish
-> >> <drewjan@cabletv.on.ca>wrote:
-> >>
-> >>> Hi Walter I wonder if that problem could be unique to your plane cuz I
-> >>> often run the pilots side tank empty to help balance my plane and get
-> >>> maximum range. I think I usually turn off the empty tank before
turning
-> >>> on
-> >>> the one with fuel in it and I've never expreienced any delay in the
-> >>> engine
-> >>> restarting.
-> >>> As for floor mounted valves consider where you place it so that if you
-> >> ever
-> >>> install floats you will be able to easily crawl through to the other side
-> >>> for docking, pumping out, refueling etc.
-> >>>
-> >>> At 11:27 AM 22/12/2009 -0800, you wrote:
-> >>>> And with only the top mounted independent valves, be very careful
when
-> >>> running one tank dry while flying. The sequence for closing and
opening
-> >> the
-> >>> valves is very critical to avoid an air lock. I know this from first hand
-> >>> experience and am able to replicate the issue on the ground.
-> >>>> We've discussed it before on the list, but here is the sequence.
When
-> >>>> you
-> >>> run one tank dry, with the other full tank closed, you must first open
-> >>> the
-> >>> full tank before you close the dry one. Otherwise, your engine will
quit,
-> >>> and you will not be able to keep it running. It will restart, but then
-> >> keep
-> >>> quitting on you.
-> >>>> The problem is that air gets trapped when you close the empty one,
and
-> >> the
-> >>> full one can't flow fast enough. It flows just enough to start your
-> >> engine,
-> >>> but it will keep quitting on you. If you keep the empty one open, the
-> >>> locked air will vent up through it, and allow the good tank to feed
down
-> >> to
-> >>> the carb. Once it is feeding OK, and the air is out, then you can close
-> >> the
-> >>> empty one.
-> >>>> It took me a while to figure this out when it happened. Luckily, I
was
-> >>>> on
-> >>> the ground when I first did it.
-> >>>> With floor mounted valves you avoid this problem, as the air can't
get
-> >>> locked in the lines above to the tanks.
-> >>>> Walter
-> >>> Drew
-> >>>
-> >>




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[Jeff Micheal]

Hey Keith,

Not to rain on your parade, but the 1st Rebel I built w/0320 could do over 8
hrs of flight (optional extended tanks). Just to go a little further, the
Rebel I flew back from Kingston, ON (Rotec R2800 equipped) also had over 8
hr of flight time with the standard 44 gal tanks (but you can squeeze more
in, if you try).

The only problem I had was trying to stay in the air for 8 hrs...........
after eating lunch on the fly.

Cheers,
Jeff


On Wed, Dec 23, 2009 at 11:07 PM, <kpierson@dcsol.com> wrote:

Ken:

You said that you have over 8 hr. of fuel, Do you have an extra
fuel tank? If so where do you have it? Or is it the header tank
that gives you the extra range? If so how big is it and where is
it? Or is your engine just that economical? I know, I know it's a
lot of questions!

Thank you

Keith P. 318R




On 12/23/2009 7:35 PM, klehman@albedo.net wrote to rebel-builders:

-> I too am a believer in a header tank. Solves the problem of air bubbles
-> when low on fuel, in turbulence, or sideslipping. I put a float switch
-> in the header tank to tell me if it is not full. I do find that I have
-> started to keep more fuel in the right tank for balance. An aileron trim
-> would probably be a better solution for me.
->
-> However when optimizing range or performance, one usually likes all
-> remaining fuel in one tank with an accurate quantity gauge so you have
-> confidence in how much is really there. Sometimes that avoids an extra
-> fuel stop for me. Kind of pointless having large tanks and carrying
-> extra fuel weight if you don't have confidence in how much is useable.
-> I don't like guessing and my Rebel performs noticeably better when I do
-> not carry excessive fuel. I have over 8 hours of fuel with full tanks.
-> In machines with multiple fuel tanks, it is not uncommon to watch a fuel
-> pressure gauge for fluctuations and then switch tanks before the engine
-> coughs. An amusing incidence of this (not in a Rebel) was accompanied by
-> a major aircraft pitch up which quite surprised me. What happened was
-> that when the engine coughed a group of parachuters all immediately
-> moved to the rear door to get out... Imagine trusting silk more than an
-> aircraft just because of a momentary hiccup ;)
->
-> I also recall an interesting night ferry trip on a newly purchased
-> aircraft. The destination had a curfew and the new owner was quite
-> nervous. It took me awhile to realize that he had previously rented
-> aircraft and had never actually flown with tanks less than half full.
->
-> I suspect that some specific Rebels may push air through the lines and
-> vent it through the carb float bowel. But many do not. One fellow used
-> transparent lines to prove that on his machine the air was being trapped
-> at the top of the vertical line. The air would not travel the last few
-> inches of horizontal tube back into the wing tank. Air in the line does
-> restrict fuel flow. He constructed a vapor separator at the top of the
-> vertical tubing to vent that air bubble. Fortunately when an engine
-> coughs, the first thing most pilots do is to switch on a tank that they
-> are sure has fuel in it which I think avoids the problem being discussed
-> below. With a header tank, I never give any of this a second thought.
->
-> Ken
->
->
-> Kevin & Nancy Mayville wrote:
-> > I am going to jump in here because I don't understand why any one
needs to
-> > drain one tank completely, I can understand burning one tank down to
say 3/4
-> > or so for balance, I would never run a tank down until the engine
coughs !
-> > I run both my tanks at the same time and I don't have any balance
problems
-> > with or without a passenger.
-> >
-> > My fuel system is a little different I have a ball valve at each aft
wing
-> > root ( which I can reach ) and then each tank flows in to a small tank
like
-> > a header tank ( aprox 2''x3'' x 16'' long mounted vertically ) aft of
the
-> > pilots seat. then the main shut off valve is just forward of the
pilots
door
-> > .
-> >
-> > This header tank eliminates any chance of air being trapped in the
fuel
-> > line. I believe this was the fix for the first generation of Glass
Stars
-> > because the fuel sloshed in the tanks and allowed air to block the
fuel
-> > lines like Walter stated, which caused some unscheduled landing .
-> >
-> > Kevin C-FRFP
-> >
-> >
-> > ----- Original Message -----
-> > From: "Walter Klatt" <Walter.Klatt@shaw.ca>
-> > To: <rebel-builders@dcsol.com>
-> > Sent: Tuesday, December 22, 2009 6:34 PM
-> > Subject: RE: [rebel-builders] Fuel slector valves
-> >
-> >
-> >> I am quite sure it will happen to any tank valve top mounted gravity
feed
-> >> set up in a Rebel or Elite. I have my tanks cross vented, plus a
snorkel
-> >> vent on each cap.
-> >>
-> >> It has to do with trapped air in the lines below the valves. The fuel
is
-> >> trying to flow down, while the air is trying to vent upwards to the
tanks,
-> >> which slows the fuel flow enough to stall the engine.
-> >>
-> >> Think about it. When you shut one tank off run to run the other one
dry,
-> >> all
-> >> the fuel will run out of both lines when the empty one finally
drains.
-> >> When
-> >> the engine runs out of fuel, there will be nothing but air left in
both
-> >> lines right up to the valves. Then if you close the empty tank valve,
you
-> >> trap the air there. When you open the full one, the flow has to fight
the
-> >> air coming up.
-> >>
-> >> If you keep the empty one open, the air has a place to get pushed out
and
-> >> vented, and no problem.
-> >>
-> >> Again, if you use the right sequence, with opening and closing the
valves,
-> >> everything is fine. But with the wrong sequence, your engine will
quit,
-> >> and
-> >> you will not get it started in time before you hit the ground,
guaranteed.
-> >>
-> >> Trust me, I have been there, and I know this issue very, very well.
And
I
-> >> can replicate it on my plane on the ground any time, and I am sure I
could
-> >> do it to yours if you have the same set up.
-> >>
-> >> Walter
-> >>
-> >> -----Original Message-----
-> >> From: mike.davis@dcsol.com [mailto:mike.davis@dcsol.com] On Behalf
Of Ron
-> >> Shannon
-> >> Sent: December 22, 2009 3:04 PM
-> >> To: rebel-builders@dcsol.com
-> >> Subject: Re: [rebel-builders] Fuel slector valves
-> >>
-> >> I believe the tank venting design will have an influence on this
switching
-> >> procedure. Not to reopen a subject that's been covered quite a bit
(see
-> >> archives) I think with dual vents and full cross vent (and perhaps
other
-> >> configurations) it may be possible to run one tank dry before
switching
as
-> >> Drew suggests -- if you're so inclined. Personally, I wouldn't
-> >> intentionally
-> >> cause an in flight shutdown except in an emergency scenario where
fuel
-> >> reserves absolutely had to be managed that tightly. Your mileage may
-> >> vary --
-> >> literally. :-)
-> >>
-> >> Ron
-> >> 254R
-> >>
-> >>
-> >> On Tue, Dec 22, 2009 at 2:41 PM, Drew Dalgleish
-> >> <drewjan@cabletv.on.ca>wrote:
-> >>
-> >>> Hi Walter I wonder if that problem could be unique to your plane cuz
I
-> >>> often run the pilots side tank empty to help balance my plane and
get
-> >>> maximum range. I think I usually turn off the empty tank before
turning
-> >>> on
-> >>> the one with fuel in it and I've never expreienced any delay in the
-> >>> engine
-> >>> restarting.
-> >>> As for floor mounted valves consider where you place it so that if
you
-> >> ever
-> >>> install floats you will be able to easily crawl through to the other
side
-> >>> for docking, pumping out, refueling etc.
-> >>>
-> >>> At 11:27 AM 22/12/2009 -0800, you wrote:
-> >>>> And with only the top mounted independent valves, be very careful
when
-> >>> running one tank dry while flying. The sequence for closing and
opening
-> >> the
-> >>> valves is very critical to avoid an air lock. I know this from first
hand
-> >>> experience and am able to replicate the issue on the ground.
-> >>>> We've discussed it before on the list, but here is the sequence.
When
-> >>>> you
-> >>> run one tank dry, with the other full tank closed, you must first
open
-> >>> the
-> >>> full tank before you close the dry one. Otherwise, your engine will
quit,
-> >>> and you will not be able to keep it running. It will restart, but
then
-> >> keep
-> >>> quitting on you.
-> >>>> The problem is that air gets trapped when you close the empty one,
and
-> >> the
-> >>> full one can't flow fast enough. It flows just enough to start your
-> >> engine,
-> >>> but it will keep quitting on you. If you keep the empty one open,
the
-> >>> locked air will vent up through it, and allow the good tank to feed
down
-> >> to
-> >>> the carb. Once it is feeding OK, and the air is out, then you can
close
-> >> the
-> >>> empty one.
-> >>>> It took me a while to figure this out when it happened. Luckily, I
was
-> >>>> on
-> >>> the ground when I first did it.
-> >>>> With floor mounted valves you avoid this problem, as the air can't
get
-> >>> locked in the lines above to the tanks.
-> >>>> Walter
-> >>> Drew
-> >>>
-> >>




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[Ken]

I actually have less than standard fuel Keith. Only 5 wing bays instead
of 6. The header tank is 2 gal. on the side wall behind the baggage area
but the soob only burns just over 4 usgph at my normal econo cruise at
about 95mph. More time to enjoy the scenery! I really like that I have
lots of power available when I choose to use it though and nothing to
adjust in flight other than a throttle. In my case the header tank is
above where a carb would be but for the EFI I have pumps inside the
header tank so most of the header fuel is indeed useable for a
precautionary landing. The header tank is also my legally required
gascolator. It is mounted to survive a 10+ g impact and fuselage
deformation.

The rotax 912 burns about the same as me. They have liquid cooled
cylinder heads. There are a few Lycoming guys that say they can get down
to abut 5 gph lean of peak EGT but I don't know any that actually do
that on a day to day basis. The Lyc's are about as good as anything in
terms of fuel per hp. when lean of peak in cruise especially with
electronic ignition advance. That often means an injected engine to keep
all cylinders running at the same mixture otherwise the first cylinder
to go lean limits leaning and the others run rich. But Lyc's (air cooled
engines) are very thirsty when running full power which means full rich
at low altitudes. And many (most?) still cruise rich of peak.

I will toss out yet another idea for fuel valve locations. I have valves
at the tank exits and they needed when parked on a slope with full tanks
or when a tire goes flat. But my right main tank gravity feed goes down
and crosses to the left side of the fuselage behind the baggage area
where the lines join at the header tank on the sidewall. There is a low
point drain. One tube comes forward from the header tank on the left
sidewall underneath the aileron push pull tube. I have a valve mounted
on the forward side of the door post to select which fuel injector
system gets fuel or to turn of the fuel. It nicely recesses into the 2"
wide space ahead of the door post.

Ken

kpierson@dcsol.com wrote:

Ken:

You said that you have over 8 hr. of fuel, Do you have an extra
fuel tank? If so where do you have it? Or is it the header tank
that gives you the extra range? If so how big is it and where is
it? Or is your engine just that economical? I know, I know it's a
lot of questions!

Thank you

Keith P. 318R

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[David Jackson]

Ken,

Could you elaborate a bit where you state: "The header tank is also my legally required
gascolator. "



Thanks

_________________________________________________________________
Windows Live: Make it easier for your friends to see what you

[Ken]

Sure, the weather is too crappy here to fly today anyhow.

The rules say I must have a gascolator but they don't say much else. The
larger the better really. So my header tank has a water drain fitting
well below the fuel exit. The pumps have an inlet screen and therefore
it is a gascolator. The inspector was quite satisfied. I suspect he has
seen a variety of homemade gascolators over the years. There continue to
be crashes with gascolators full of water or debris so a large one is a
good thing!
Also our wing exits are not really at the lowest possible point of the
wing tank. So it is quite conceivable to accumulate a cup or two of
water in a wing tank and then have it exit in a significant amount
instead of a few drops at a time.

Ken

David Jackson wrote:

Ken,

Could you elaborate a bit where you state: "The header tank is also my legally required
gascolator. "


Thanks

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[Kevin & Nancy Mayville]

Hey Wayne

I agree with you regarding the head pressure, But with all due respect I
hope I am never in the situation that I am that low on fuel that I need to
run my tanks dry and plan for a forced landing due to fuel starvation, first
of all its against the regs and not all forced landings work out well, I
lost couple of friends that way and I am sure every one else can say the
same. ( we all should practice a few now and again ).
I understand you guys have less access to fuel than we do in the south and
flying is a little different for you float guys .Thanks

Happy Hoildays to the Group

Kevin


----- Original Message -----
From: "Wayne G. O'Shea" <oifa@irishfield.on.ca>
To: <rebel-builders@dcsol.com>
Sent: Wednesday, December 23, 2009 10:43 PM
Subject: Re: [rebel-builders] Fuel slector valves

If you're 30 miles from home.. with no where to land.. and the fuel
gauges
banged empty a few miles back.. you'd be smart to have one side shut off
and
then time just how far you get before sputter and then hope that you get
the
same time out of the other side.... so you know if you will make it or if
you should land on a highway/farmers field or the first thing that looks
close to a landing patch comes along! Leaving it on both... you'll have no
idea how far you can get.

Now that I've looked at the pictures of the build on your Rebel...with the
header tank so low and far back in the fuselage that it wouldn't give you
any head pressure when the wing tank quits feeding it.. I'm surprised they
didnt' install a fuel pump on your motor to pass final inspection. You
could
never run a tank to empty with that system, because at engine sputter by
the
time the other tank filled the header tank back up you'd be a glider
already.

Can you reach that forward fuel valve with your shoulder belt done up?

----- Original Message -----
From: "Kevin & Nancy Mayville" <knmay@sympatico.ca>
To: <rebel-builders@dcsol.com>
Sent: Wednesday, December 23, 2009 9:18 PM
Subject: Re: [rebel-builders] Fuel slector valves

I am going to jump in here because I don't understand why any one needs
to
drain one tank completely, I can understand burning one tank down to say
3/4
or so for balance, I would never run a tank down until the engine coughs
!
I run both my tanks at the same time and I don't have any balance
problems
with or without a passenger.

My fuel system is a little different I have a ball valve at each aft wing
root ( which I can reach ) and then each tank flows in to a small tank
like
a header tank ( aprox 2''x3'' x 16'' long mounted vertically ) aft of the
pilots seat. then the main shut off valve is just forward of the pilots
door
.

This header tank eliminates any chance of air being trapped in the fuel
line. I believe this was the fix for the first generation of Glass Stars
because the fuel sloshed in the tanks and allowed air to block the fuel
lines like Walter stated, which caused some unscheduled landing .

Kevin C-FRFP


----- Original Message -----
From: "Walter Klatt" <Walter.Klatt@shaw.ca>
To: <rebel-builders@dcsol.com>
Sent: Tuesday, December 22, 2009 6:34 PM
Subject: RE: [rebel-builders] Fuel slector valves

I am quite sure it will happen to any tank valve top mounted gravity feed
set up in a Rebel or Elite. I have my tanks cross vented, plus a snorkel
vent on each cap.

It has to do with trapped air in the lines below the valves. The fuel is
trying to flow down, while the air is trying to vent upwards to the
tanks,
which slows the fuel flow enough to stall the engine.

Think about it. When you shut one tank off run to run the other one dry,
all
the fuel will run out of both lines when the empty one finally drains.
When
the engine runs out of fuel, there will be nothing but air left in both
lines right up to the valves. Then if you close the empty tank valve,
you
trap the air there. When you open the full one, the flow has to fight
the
air coming up.

If you keep the empty one open, the air has a place to get pushed out
and
vented, and no problem.

Again, if you use the right sequence, with opening and closing the
valves,
everything is fine. But with the wrong sequence, your engine will quit,
and
you will not get it started in time before you hit the ground,
guaranteed.

Trust me, I have been there, and I know this issue very, very well. And
I
can replicate it on my plane on the ground any time, and I am sure I
could
do it to yours if you have the same set up.

Walter

-----Original Message-----
From: mike.davis@dcsol.com [mailto:mike.davis@dcsol.com] On Behalf Of
Ron
Shannon
Sent: December 22, 2009 3:04 PM
To: rebel-builders@dcsol.com
Subject: Re: [rebel-builders] Fuel slector valves

I believe the tank venting design will have an influence on this
switching
procedure. Not to reopen a subject that's been covered quite a bit (see
archives) I think with dual vents and full cross vent (and perhaps other
configurations) it may be possible to run one tank dry before switching
as
Drew suggests -- if you're so inclined. Personally, I wouldn't
intentionally
cause an in flight shutdown except in an emergency scenario where fuel
reserves absolutely had to be managed that tightly. Your mileage may
vary --
literally. :-)

Ron
254R


On Tue, Dec 22, 2009 at 2:41 PM, Drew Dalgleish
<drewjan@cabletv.on.ca>wrote:
ever the keep the engine, to the

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[Wayne G. O'Shea]

I wasn't stating it as a normal flying procedure Kevin....99.9% of the time
I have way too much fuel with me for the task at hand. However..shit happens
to even the best..and when it does you'd have to know how to deal with it.

When FSS tells you a beautiful CAVU day from Temagami to Thunder Bay.. and
you end up droning around for bright spots to make Marathon.. what should
have been a 3 hour flight and you arrive with 4 gallons of fuel left from
your 5 hour range.. the odd trick my keep you alive.

I do seriously want to know if you can reach that lower main fuel shut off
valve when all belted up.

Have a great Christmas!!!!

Wayne

----- Original Message -----
From: "Kevin & Nancy Mayville" <knmay@sympatico.ca>
To: <rebel-builders@dcsol.com>
Sent: Thursday, December 24, 2009 4:16 PM
Subject: Re: [rebel-builders] Fuel slector valves

Hey Wayne

I agree with you regarding the head pressure, But with all due respect I
hope I am never in the situation that I am that low on fuel that I need to
run my tanks dry and plan for a forced landing due to fuel starvation,
first
of all its against the regs and not all forced landings work out well, I
lost couple of friends that way and I am sure every one else can say the
same. ( we all should practice a few now and again ).
I understand you guys have less access to fuel than we do in the south and
flying is a little different for you float guys .Thanks

Happy Hoildays to the Group

Kevin


----- Original Message -----
From: "Wayne G. O'Shea" <oifa@irishfield.on.ca>
To: <rebel-builders@dcsol.com>
Sent: Wednesday, December 23, 2009 10:43 PM
Subject: Re: [rebel-builders] Fuel slector valves

If you're 30 miles from home.. with no where to land.. and the fuel
gauges
banged empty a few miles back.. you'd be smart to have one side shut off
and
then time just how far you get before sputter and then hope that you get
the
same time out of the other side.... so you know if you will make it or if
you should land on a highway/farmers field or the first thing that looks
close to a landing patch comes along! Leaving it on both... you'll have
no
idea how far you can get.

Now that I've looked at the pictures of the build on your Rebel...with
the
header tank so low and far back in the fuselage that it wouldn't give you
any head pressure when the wing tank quits feeding it.. I'm surprised
they
didnt' install a fuel pump on your motor to pass final inspection. You
could
never run a tank to empty with that system, because at engine sputter by
the
time the other tank filled the header tank back up you'd be a glider
already.

Can you reach that forward fuel valve with your shoulder belt done up?

----- Original Message -----
From: "Kevin & Nancy Mayville" <knmay@sympatico.ca>
To: <rebel-builders@dcsol.com>
Sent: Wednesday, December 23, 2009 9:18 PM
Subject: Re: [rebel-builders] Fuel slector valves

I am going to jump in here because I don't understand why any one needs
to
drain one tank completely, I can understand burning one tank down to say
3/4
or so for balance, I would never run a tank down until the engine coughs
!
I run both my tanks at the same time and I don't have any balance
problems
with or without a passenger.

My fuel system is a little different I have a ball valve at each aft
wing
root ( which I can reach ) and then each tank flows in to a small tank
like
a header tank ( aprox 2''x3'' x 16'' long mounted vertically ) aft of
the
pilots seat. then the main shut off valve is just forward of the pilots
door
.

This header tank eliminates any chance of air being trapped in the fuel
line. I believe this was the fix for the first generation of Glass Stars
because the fuel sloshed in the tanks and allowed air to block the fuel
lines like Walter stated, which caused some unscheduled landing .

Kevin C-FRFP


----- Original Message -----
From: "Walter Klatt" <Walter.Klatt@shaw.ca>
To: <rebel-builders@dcsol.com>
Sent: Tuesday, December 22, 2009 6:34 PM
Subject: RE: [rebel-builders] Fuel slector valves



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[Kevin & Nancy Mayville]

Wayne

You are correct " shit " happens and I know what you are saying about FSS I
had it happen on a trip home after departing Thunder Bay ! Like I said you
guys in the north have different challenges, I have never heard of any one
drain a tank to time the amount of time left in the other tank, makes sense,
but I don't think I want to try it .( maybe on the ground ) LOL

I have to get back to you on the main shut off Wayne, to be honest I shut it
off after every flight, but I really can't remember if I pop my belt off or
not when I shut it off ( a routine you don't think about ) .
I will check it out next time I am near the airport.

Thanks
Kevin
----- Original Message -----
From: "Wayne G. O'Shea" <oifa@irishfield.on.ca>
To: <rebel-builders@dcsol.com>
Sent: Thursday, December 24, 2009 4:35 PM
Subject: Re: [rebel-builders] Fuel slector valves

I wasn't stating it as a normal flying procedure Kevin....99.9% of the time
I have way too much fuel with me for the task at hand. However..shit
happens
to even the best..and when it does you'd have to know how to deal with it.

When FSS tells you a beautiful CAVU day from Temagami to Thunder Bay.. and
you end up droning around for bright spots to make Marathon.. what should
have been a 3 hour flight and you arrive with 4 gallons of fuel left from
your 5 hour range.. the odd trick my keep you alive.

I do seriously want to know if you can reach that lower main fuel shut off
valve when all belted up.

Have a great Christmas!!!!

Wayne

----- Original Message -----
From: "Kevin & Nancy Mayville" <knmay@sympatico.ca>
To: <rebel-builders@dcsol.com>
Sent: Thursday, December 24, 2009 4:16 PM
Subject: Re: [rebel-builders] Fuel slector valves

Hey Wayne

I agree with you regarding the head pressure, But with all due respect I
hope I am never in the situation that I am that low on fuel that I need
to
run my tanks dry and plan for a forced landing due to fuel starvation,
first
of all its against the regs and not all forced landings work out well, I
lost couple of friends that way and I am sure every one else can say the
same. ( we all should practice a few now and again ).
I understand you guys have less access to fuel than we do in the south
and
flying is a little different for you float guys .Thanks

Happy Hoildays to the Group

Kevin


----- Original Message -----
From: "Wayne G. O'Shea" <oifa@irishfield.on.ca>
To: <rebel-builders@dcsol.com>
Sent: Wednesday, December 23, 2009 10:43 PM
Subject: Re: [rebel-builders] Fuel slector valves

If you're 30 miles from home.. with no where to land.. and the fuel
gauges
banged empty a few miles back.. you'd be smart to have one side shut off
and
then time just how far you get before sputter and then hope that you get
the
same time out of the other side.... so you know if you will make it or
if
you should land on a highway/farmers field or the first thing that looks
close to a landing patch comes along! Leaving it on both... you'll have
no
idea how far you can get.

Now that I've looked at the pictures of the build on your Rebel...with
the
header tank so low and far back in the fuselage that it wouldn't give
you
any head pressure when the wing tank quits feeding it.. I'm surprised
they
didnt' install a fuel pump on your motor to pass final inspection. You
could
never run a tank to empty with that system, because at engine sputter by
the
time the other tank filled the header tank back up you'd be a glider
already.

Can you reach that forward fuel valve with your shoulder belt done up?

----- Original Message -----
From: "Kevin & Nancy Mayville" <knmay@sympatico.ca>
To: <rebel-builders@dcsol.com>
Sent: Wednesday, December 23, 2009 9:18 PM
Subject: Re: [rebel-builders] Fuel slector valves




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