Today's Message Index:
----------------------
1. 04:51 AM - Re: Relocating red cube (Kelly McMullen)
2. 06:14 AM - Re: Relocating red cube (kearney)
3. 06:22 AM - Re: Re: Relocating red cube (Kelly McMullen)
4. 07:33 AM - Re: Re: Relocating red cube (Dave Leikam)
5. 07:45 AM - Re: Relocating red cube (Robert Jones)
6. 07:49 AM - Re: Relocating red cube (Peter)
7. 08:18 AM - Re: Relocating red cube (Robert Jones)
8. 01:16 PM - Re: Relocating red cube (Dan Charrois)
9. 06:15 PM - Re: Relocating red cube (Kelly McMullen)
Message 1
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| Subject: | Re: Relocating red cube |
What you say is correct, but should be clarified. If the line is on or
connects to the engine it must be hose due to the vibration. If in the
tunnel, rigid line is okay.
There are two types of hose that can be used. Standard fuel line with
external fire sleeve is okay. When I got my kit, Vans supplied standard
hose without fire sleeve. It needed to have fire sleeve added. Integral
fire sleeve hose with teflon core is nicer and longer lasting. It is
more flexible, smaller external diameter and does not deteriorate from
heat or age. Fuel lines are best fabricated by professional hose shops.
It may cost you 50 or 100 more, but will eliminate one source of
substantial hazard. While as an A&P I have experience fabricating hoses,
given the time it takes, the need for tooling and proper pressure
testing, I buy my fuel lines from professional aviation hose shop. Just
one more choice to make for each builder.
Kelly
On 1/20/2019 9:03 PM, Dave Leikam wrote:
>
> Whatever you do, use flexible fire sleeve hose after transducer. DO NOT use
ridged aluminum fuel line after the transducer or before the spider like under
the fuel selector.
> Suspend the transducer with minimal support for maximum flexibility
> At least one -10 had engine failure due to cracked fuel line because of this.
It ended ok with emergency landing at an airport out of IFR. Lots of vibration
down there.
>
> Dave Leikam
> N89DA
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| Subject: | Re: Relocating red cube |
arplnplt(at)gmail.com wrote:
> Whatever you do, use flexible fire sleeve hose after transducer. DO NOT use
ridged aluminum fuel line after the transducer or before the spider like under
the fuel selector.
> Suspend the transducer with minimal support for maximum flexibility
> At least one -10 had engine failure due to cracked fuel line because of this.
It ended ok with emergency landing at an airport out of IFR. Lots of vibration
down there.
>
> Dave Leikam
> N89DA
Keeping in mind comments of those with greater experience (Hi Kelley), I would
disagree with with Dave's minimal support comment. I would think that vibration
is only a problem if the transducer does not move in sync with the engine. If
the transducer is securely mounted to the engine, then it will move with the
engine and so there would be no vibration issue. There are soft aluminium tubes
used on the engine and these are not a problem as they are attached to the
engine at both ends.
It is when things vibrate differently from what it is attached to that things get
sporty!
I didn't find it hard to make my own braided steel fuel hoses using hose ends and
hose tubing from a lo cal speed shop. I used Aeroquip hoses / ends as I wanted
to know the provenance of the parts.
Use of a Koul Tool (also available at a speed shop) made making up the hoses fast
and simple.
Cheers
Les
RV10: C-GCWZ Sold
RV10: C-GROK Nearing completion
Read this topic online here:
http://forums.matronics.com/viewtopic.php?p=487123#487123
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| Subject: | Re: Relocating red cube |
Les,
I haven't found it a problem to mount the cube to the engine, but EI
recommends against doing that. As for making hoses, true, not difficult,
but there are easy ways to screw it up and not know that it isn't right
if you don't have the experience to inspect the finished hose. Most
shops don't charge that much to do it for you, and properly pressure
test the hose.
On 1/21/2019 7:11 AM, kearney wrote:
>
>
> arplnplt(at)gmail.com wrote:
>> Whatever you do, use flexible fire sleeve hose after transducer. DO NOT use
ridged aluminum fuel line after the transducer or before the spider like under
the fuel selector.
>> Suspend the transducer with minimal support for maximum flexibility
>> At least one -10 had engine failure due to cracked fuel line because of this.
It ended ok with emergency landing at an airport out of IFR. Lots of vibration
down there.
>>
>> Dave Leikam
>> N89DA
>
>
> Keeping in mind comments of those with greater experience (Hi Kelley), I would
disagree with with Dave's minimal support comment. I would think that vibration
is only a problem if the transducer does not move in sync with the engine.
If the transducer is securely mounted to the engine, then it will move with the
engine and so there would be no vibration issue. There are soft aluminium
tubes used on the engine and these are not a problem as they are attached to the
engine at both ends.
>
> It is when things vibrate differently from what it is attached to that things
get sporty!
>
> I didn't find it hard to make my own braided steel fuel hoses using hose ends
and hose tubing from a lo cal speed shop. I used Aeroquip hoses / ends as I wanted
to know the provenance of the parts.
>
> Use of a Koul Tool (also available at a speed shop) made making up the hoses
fast and simple.
>
> Cheers
>
> Les
>
> RV10: C-GCWZ Sold
> RV10: C-GROK Nearing completion
>
>
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=487123#487123
>
>
>
>
>
>
>
>
>
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| Subject: | Re: Relocating red cube |
I have 600+ hours on my -10. My transducer is mounted just in front of the servo
with flex hose in and out. I made a tab from aluminum stock connected to the
air cleaner below and clamped to the hose above that allows the whole thing
to move slightly forward and aft. 600 hours, no cracks no problem.
I do not have Red Cube. I have the one that comes with Garmin 900x from 2010.
Cant remember the manufacturer. Talked directly to them and was told absolutely
do not mount directly to the engine for a number of reasons. Also instructed
to place after the servo before the spider.
My fuel totals are and have always been within .1 gal of of actual burn.
Extremely accurate.
My 2 cents.
Dave Leikam
N89DA
> On Jan 21, 2019, at 8:19 AM, Kelly McMullen <kellym@aviating.com> wrote:
>
>
> Les,
> I haven't found it a problem to mount the cube to the engine, but EI recommends
against doing that. As for making hoses, true, not difficult, but there are
easy ways to screw it up and not know that it isn't right if you don't have the
experience to inspect the finished hose. Most shops don't charge that much
to do it for you, and properly pressure test the hose.
>
>> On 1/21/2019 7:11 AM, kearney wrote:
>> arplnplt(at)gmail.com wrote:
>>> Whatever you do, use flexible fire sleeve hose after transducer. DO NOT use
ridged aluminum fuel line after the transducer or before the spider like under
the fuel selector.
>>> Suspend the transducer with minimal support for maximum flexibility
>>> At least one -10 had engine failure due to cracked fuel line because of this.
It ended ok with emergency landing at an airport out of IFR. Lots of vibration
down there.
>>>
>>> Dave Leikam
>>> N89DA
>> Keeping in mind comments of those with greater experience (Hi Kelley), I would
disagree with with Dave's minimal support comment. I would think that vibration
is only a problem if the transducer does not move in sync with the engine.
If the transducer is securely mounted to the engine, then it will move with
the engine and so there would be no vibration issue. There are soft aluminium
tubes used on the engine and these are not a problem as they are attached to
the engine at both ends.
>> It is when things vibrate differently from what it is attached to that things
get sporty!
>> I didn't find it hard to make my own braided steel fuel hoses using hose ends
and hose tubing from a lo cal speed shop. I used Aeroquip hoses / ends as I
wanted to know the provenance of the parts.
>> Use of a Koul Tool (also available at a speed shop) made making up the hoses
fast and simple.
>> Cheers
>> Les
>> RV10: C-GCWZ Sold
>> RV10: C-GROK Nearing completion
>> Read this topic online here:
>> http://forums.matronics.com/viewtopic.php?p=487123#487123
>
>
>
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| Subject: | Re: Relocating red cube |
Kelly is correct. Any rigid lines in the engine compartment are going to crack.
Flexible lines are a must. I used the braided line with Teflon core and fire
sleeve for everything. I am fortunate that I have a hose shop (All Hose) close
by. They have also been very helpful with any standard or unusual fitting that
I needed. I used stainless steel fittings for all the fuel system, firewall
forward. I did not bother with Stainless Steel for the oil lines. After all my
oil cooler is aluminum and will melt with a fuel fire anyway. The main thing
is to make sure that never happens.
Robert Jones
> On Jan 21, 2019, at 04:48, Kelly McMullen <kellym@aviating.com> wrote:
>
>
> What you say is correct, but should be clarified. If the line is on or connects
to the engine it must be hose due to the vibration. If in the tunnel, rigid
line is okay.
> There are two types of hose that can be used. Standard fuel line with external
fire sleeve is okay. When I got my kit, Vans supplied standard hose without
fire sleeve. It needed to have fire sleeve added. Integral fire sleeve hose with
teflon core is nicer and longer lasting. It is more flexible, smaller external
diameter and does not deteriorate from heat or age. Fuel lines are best fabricated
by professional hose shops. It may cost you 50 or 100 more, but will
eliminate one source of substantial hazard. While as an A&P I have experience
fabricating hoses, given the time it takes, the need for tooling and proper pressure
testing, I buy my fuel lines from professional aviation hose shop. Just
one more choice to make for each builder.
> Kelly
>
>> On 1/20/2019 9:03 PM, Dave Leikam wrote:
>> Whatever you do, use flexible fire sleeve hose after transducer. DO NOT use
ridged aluminum fuel line after the transducer or before the spider like under
the fuel selector.
>> Suspend the transducer with minimal support for maximum flexibility
>> At least one -10 had engine failure due to cracked fuel line because of this.
It ended ok with emergency landing at an airport out of IFR. Lots of vibration
down there.
>> Dave Leikam
>> N89DA
>
>
>
>
Message 6
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| Subject: | Re: Relocating red cube |
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Message 7
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| Subject: | Re: Relocating red cube |
Airflow Performance makes a bypass valve and fittings to mount just before t
he fuel distributor. It can=99t be used in flight because all fuel is b
ypassed back to a Wing tank. Fuel vapors forming after the engine driven fue
l pump are very unlikely because of the higher pressure. Vapors forming befo
re the electric fuel pump are the most likely because the pump is sucking in
stead of pushing, lowering the pressure. I find it hard to believe that pilo
ts are experiencing vapors forming after the engine driven fuel pump. If the
re are vapors forward they were formed earlier, or after shutdown because of
residual heat. The Airflow Performance calve solves the last problem by pur
ging hot fuel and vapors back to a fuel tank before start.
Robert Jones
> On Jan 21, 2019, at 07:45, Peter <peter@peteraringer.de> wrote:
>
> Hi,
>
> regarding the vapor lock problem:
> What about a return line into one wing with a valve you can open and close
in flight??
> Before hot starts you could open the valve and remove the air in the fuel l
ines with the electric fuel pump flushing with cold fuel from the wing tank.
After takeoff you close the valve to have correct fuel flow readings...
>
> Greetings from Germany
>
>
> Peter Aringer
>
>> Am 21.01.2019 um 14:03 schrieb Kelly McMullen <kellym@aviating.com>:
>>
>>
>> What you say is correct, but should be clarified. If the line is on or
>> connects to the engine it must be hose due to the vibration. If in the
>> tunnel, rigid line is okay.
>> There are two types of hose that can be used. Standard fuel line with
>> external fire sleeve is okay. When I got my kit, Vans supplied standard
>> hose without fire sleeve. It needed to have fire sleeve added. Integral
>> fire sleeve hose with teflon core is nicer and longer lasting. It is
>> more flexible, smaller external diameter and does not deteriorate from
>> heat or age. Fuel lines are best fabricated by professional hose shops.
>> It may cost you 50 or 100 more, but will eliminate one source of
>> substantial hazard. While as an A&P I have experience fabricating hoses,
>> given the time it takes, the need for tooling and proper pressure
>> testing, I buy my fuel lines from professional aviation hose shop. Just
>> one more choice to make for each builder.
>> Kelly
>>
>>> On 1/20/2019 9:03 PM, Dave Leikam wrote:
>>>
>>> Whatever you do, use flexible fire sleeve hose after transducer. DO NO
T use ridged aluminum fuel line after the transducer or before the spider li
ke under the fuel selector.
>>> Suspend the transducer with minimal support for maximum flexibility
>>> At least one -10 had engine failure due to cracked fuel line because of t
his. It ended ok with emergency landing at an airport out of IFR. Lots of v
ibration down there.
>>>
>>> Dave Leikam
>>> N89DA
>>
==========================
=========
==========================
=========
==========================
=========
==========================
=========
==========================
=========
>>
>>
>>
>>
>>
Message 8
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| Subject: | Re: Relocating red cube |
Hi again everyone.
To add some more info to the discussion, I just heard back from a tech at Electronics
International (the makers of the red cube) to get their take on placement.
Obviously, they disagree with the placement in the tunnel between the electric
and mechanical pump. In addition to the "water hammer" effect of placing it in
that location that causes erratically high readings, they said their transducers
were designed for fuel to be pushed through, not sucked through.
As far as the discussion of where specifically to locate it past both pumps (between
pump to servo or servo to spider), they suggested that in a case without
a return line from the servo they suggest their diagram on page 18 (between the
pump and servo). They said their rationale for not placing it between servo
to spider in that situation is based on maintaining the calibrated pressure
on the outlet from the servo (based on the number of orifices/volume it's serving).
Apparently, the cube in that position has the potential of changing this
pressure provided by the servo slightly, and as such their STC for installation
without a return line disallows that. With that said, they know that many
homebuilt owners have installed it between the servo and divider, without return
lines, and obviously it's working for them.
Dan
---
Dan Charrois
President, Syzygy Research & Technology
Phone: 780-961-2213
Message 9
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| Subject: | Re: Relocating red cube |
There is not a vapor lock problem. Some engines will run a bit rough at
taxi power after a hot start, but that is uneven fuel delivery, and maybe
some vapor, but it isn't a lock. Hot starting is the challenge of getting
the right mixture during cranking, not vapor lock. I have been flying with
a Bendix RSA-5 system for 20 years now. On the 200 hp 4 cyl Lycoming in
the Mooney preceding my RV-10, it was easy to flood the engine when hot.
With the 6 cyl 540 engine, it isn't as prone to flooding, it is just
getting the right mixture. The mechanical pump doesn't necessarily generate
enough pressure at cranking speeds. I get better hot start reliability with
the boost pump on, and then bring in the mixture slowly. When right, the
engine fires and keeps running. Without the boost pump it often fires and
then quits. W'ith the RSA system it is just a matter of finding what
procedure is most reliable. If the approach from the mixture cutoff isn't
working, and adding throttle doesn't help, you can perhaps go to full rich
and flood engine, then lean out until it fires.
Sent from my TRS-80 Model 100
On Mon, Jan 21, 2019 at 8:54 AM Peter <peter@peteraringer.de> wrote:
> Hi,
>
> regarding the vapor lock problem:
> What about a return line into one wing with a valve you can open and close
> in flight??
> Before hot starts you could open the valve and remove the air in the fuel
> lines with the electric fuel pump flushing with cold fuel from the wing
> tank. After takeoff you close the valve to have correct fuel flow
> readings...
>
> Greetings from Germany
>
>
> Peter Aringer
>
> Am 21.01.2019 um 14:03 schrieb Kelly McMullen <kellym@aviating.com>:
>
>
> What you say is correct, but should be clarified. If the line is on or
> connects to the engine it must be hose due to the vibration. If in the
> tunnel, rigid line is okay.
> There are two types of hose that can be used. Standard fuel line with
> external fire sleeve is okay. When I got my kit, Vans supplied standard
> hose without fire sleeve. It needed to have fire sleeve added. Integral
> fire sleeve hose with teflon core is nicer and longer lasting. It is
> more flexible, smaller external diameter and does not deteriorate from
> heat or age. Fuel lines are best fabricated by professional hose shops.
> It may cost you 50 or 100 more, but will eliminate one source of
> substantial hazard. While as an A&P I have experience fabricating hoses,
> given the time it takes, the need for tooling and proper pressure
> testing, I buy my fuel lines from professional aviation hose shop. Just
> one more choice to make for each builder.
> Kelly
>
> On 1/20/2019 9:03 PM, Dave Leikam wrote:
>
>
>
> Whatever you do, use flexible fire sleeve hose after transducer. DO NOT
> use ridged aluminum fuel line after the transducer or before the spider
> like under the fuel selector.
>
> Suspend the transducer with minimal support for maximum flexibility
>
> At least one -10 had engine failure due to cracked fuel line because of
> this. It ended ok with emergency landing at an airport out of IFR. Lots
> of vibration down there.
>
>
> Dave Leikam
>
> N89DA
>
>
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