Today's Message Index:
----------------------
1. 04:31 AM - Re: Just a couple of questions (Michel Therrien)
2. 05:14 AM - Re: Just a couple of questions (Jeff Davidson)
3. 06:02 AM - Re: Just a couple of questions (Michel Therrien)
4. 06:24 AM - Re: Just a couple of questions (Bryan Martin)
Message 1
| INDEX | Back to Main INDEX |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Just a couple of questions |
Jeff, i do not use a selector valve. Iselect tanks by selecting the fuel pump
to be activated. My valves are for shutoff. I found that the pump not in
use will allow a bit of flow in the backward direction. However, i also found
that with the ACS check valve, the backward flow will be more than twice as much
with a check vqlve in place. I think this might be because of the pulsating
action of the pump and the sync of the check valve action with the one internal
to the pump.
Sent from my iPad
On Aug 26, 2011, at 6:58 PM, Jeff Davidson <jeffrey_davidson@earthlink.net> wrote:
>
> Michel,
> I have check valves on both sides next to the tanks. So the valve on the opposite
tank stops the flow if the selector valve leaks a little. The selector
valve only allows flow from one side or the other at any one time as long as it
is fully in the detent. My Facet pumps are operated independently, usually
one at a time as intended. There is documentation that the Facet pumps do allow
fuel flow in the backwards direction when not operating. If anything, the
check valves are overkill but Chris himself drew it up for me. And Fred Hulen,
or was it Hinde, anyway the fluid design engineer on this list agreed. Anyway,
it seems to work for me.
> Jeff
>
>
> -----Original Message-----
>> From: Michel Therrien <mtherr@yahoo.com>
>> Sent: Aug 24, 2011 8:41 PM
>> To: "zenith601-list@matronics.com" <zenith601-list@matronics.com>
>> Subject: Re: Zenith601-List: Just a couple of questions
>>
>>
>> Jeff, when i tested check valves in line with fuel pumps, i found there would
be much more back flow into the opposite tank with a check valve than without...
So i decided to deinstall them.
>>
>> Sent from my iPad
>>
>> On Aug 24, 2011, at 7:40 PM, Jeff Davidson <jeffrey_davidson@earthlink.net>
wrote:
>>
>>>
>>> ... installed Facet pumps, 40105 I believe, next to both tanks. After that
per Chris Heintz' recommendation, are check valves to keep fuel from re-entering
the tanks. ...
>>>
>>>
>>
>>
>>
>>
>>
>
>
>
>
>
Message 2
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Just a couple of questions |
Michel,
I understand. I had already designed my system similar to that in the Piper Warrior
that I learned to fly in before I learned about what is a simpler design
without the selector valve. I do still alternate the active pumps too but also
must change the selector valve in coordination. So the procedure for changing
tanks is to check fuel pressure, turn on the opposite pump, move the selector,
turn off the origonal pump, and check fuel pressure after the change. I
presume that your procedure involves shutting off the valve for the inactive tank.
That difference in design may account for the difference in the behavior
of the check valve. But yes, the Facet pumps do allow some flow back into the
opposite tank.
Jeff
-----Original Message-----
>From: Michel Therrien <mtherr@yahoo.com>
>Sent: Aug 27, 2011 7:28 AM
>To: "zenith601-list@matronics.com" <zenith601-list@matronics.com>
>Subject: Re: Zenith601-List: Just a couple of questions
>
>
>Jeff, i do not use a selector valve. Iselect tanks by selecting the fuel pump
to be activated. My valves are for shutoff. I found that the pump not in
use will allow a bit of flow in the backward direction. However, i also found
that with the ACS check valve, the backward flow will be more than twice as
much with a check vqlve in place. I think this might be because of the pulsating
action of the pump and the sync of the check valve action with the one internal
to the pump.
>
>Sent from my iPad
>
>On Aug 26, 2011, at 6:58 PM, Jeff Davidson <jeffrey_davidson@earthlink.net> wrote:
>
>>
>> Michel,
>> I have check valves on both sides next to the tanks. So the valve on the opposite
tank stops the flow if the selector valve leaks a little. The selector
valve only allows flow from one side or the other at any one time as long as
it is fully in the detent. My Facet pumps are operated independently, usually
one at a time as intended. There is documentation that the Facet pumps do allow
fuel flow in the backwards direction when not operating. If anything, the
check valves are overkill but Chris himself drew it up for me. And Fred Hulen,
or was it Hinde, anyway the fluid design engineer on this list agreed. Anyway,
it seems to work for me.
>> Jeff
>>
>>
>> -----Original Message-----
>>> From: Michel Therrien <mtherr@yahoo.com>
>>> Sent: Aug 24, 2011 8:41 PM
>>> To: "zenith601-list@matronics.com" <zenith601-list@matronics.com>
>>> Subject: Re: Zenith601-List: Just a couple of questions
>>>
>>>
>>> Jeff, when i tested check valves in line with fuel pumps, i found there would
be much more back flow into the opposite tank with a check valve than without...
So i decided to deinstall them.
>>>
>>> Sent from my iPad
>>>
>>> On Aug 24, 2011, at 7:40 PM, Jeff Davidson <jeffrey_davidson@earthlink.net>
wrote:
>>>
>>>>
>>>> ... installed Facet pumps, 40105 I believe, next to both tanks. After that
per Chris Heintz' recommendation, are check valves to keep fuel from re-entering
the tanks. ...
>>>>
>>>>
>>>
>>>
>>>
>>>
>>>
>>
>>
>>
>>
>>
>
>
Message 3
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Just a couple of questions |
-=0AOK, I see...- I just found on my web site the information on the te
st I did back when I installed my fuel system: =0A-=0A"Fuel pump check va
lve =0Atest=0AI checked how much gas was flowing through the system in the
=0Aopposite tank. Well, there is a leak. The fuel pump has internal check
valves, =0Abut they are not perfect. I tried putting a check valve in ser
ies with the fuel =0Apump and the result is worse! Instead of about 0.5 to
0.8 liter per hour, I get =0A3 to 4 liter per hour of cross-transfer. Thi
s may be explained by the fact that =0Atwo check valve in series somewhat c
ancel their capabilities (there is no flow =0Ato push the ball or diaphragm
in the check valve). I removed the check valve I =0Aput in there (and had
to replace a segment of fuel line)."=0A-=0AOn another note, I noticed it
is tough to get to my web site as the Zenith Builder Ring link apparently
highjack the web page.- I found that by cancelling the page load as soon
as my page shows up allow it to be seen.- I would like to correct that, b
ut I no longer have the software to update my site... when I have time, I'l
l try to resolve that.=0A-=0A----------------------------=0AMichel Therri
en CH601-HD, C-GZGQ=0Ahttp://mthobby.pcperfect.com/ch601=0Ahttp://pages.inf
init.net/mthobby=0A=0AFrom: Jeff Davidson <jeffrey_davidson@earthlink.net>
=0ATo: zenith601-list@matronics.com=0ASent: Saturday, August 27, 2011 8:11:
49 AM=0ASubject: Re: Zenith601-List: Just a couple of questions=0A=0A--> Ze
nith601-List message posted by: Jeff Davidson <jeffrey_davidson@earthlink.n
et>=0A=0AMichel,=0AI understand.- I had already designed my system simila
r to that in the Piper Warrior that I learned to fly in before I learned ab
out what is a simpler design without the selector valve.- I do still alte
rnate the active pumps too but also must change the selector valve in coord
ination.- So the procedure for changing tanks is to check fuel pressure,
turn on the opposite pump, move the selector, turn off the origonal pump, a
nd check fuel pressure after the change.- I presume that your procedure i
nvolves shutting off the valve for the inactive tank.- That difference in
design may account for the difference in the behavior of the check valve.
- But yes, the Facet pumps do allow some flow back into the opposite tank
.=0AJeff=0A=0A=0A-----Original Message-----=0A>From: Michel Therrien <mther
r@yahoo.com>=0A>Sent: Aug 27, 2011 7:28 AM=0A>To: "zenith601-list@matronics
.com" <zenith601-list@matronics.com>=0A>Subject: Re: Zenith601-List: Just a
errien <mtherr@yahoo.com>=0A>=0A>Jeff, i do not use a selector valve.- I
select tanks by selecting the fuel pump to be activated.- My valves are
for shutoff.- - I found that the pump not in use will allow a bit of fl
ow in the backward direction. However, i also found that with the ACS check
valve, the backward flow will be more than twice as much with a check vqlv
e in place.- I think this might be because of the pulsating action of th
e pump and the sync of the check valve action with the one internal to the
pump.=0A>=0A>Sent from my iPad=0A>=0A>On Aug 26, 2011, at 6:58 PM, Jeff Dav
idson <jeffrey_davidson@earthlink.net> wrote:=0A>=0A>> --> Zenith601-List m
essage posted by: Jeff Davidson <jeffrey_davidson@earthlink.net>=0A>> =0A>>
Michel,=0A>> I have check valves on both sides next to the tanks.- So th
e valve on the opposite tank stops the flow if the selector valve leaks a l
ittle.- The selector valve only allows flow from one side or the other at
any one time as long as it is fully in the detent.- My Facet pumps are o
perated independently, usually one at a time as intended.- There is docum
entation that the Facet pumps do allow fuel flow in the backwards direction
when not operating.- If anything, the check valves are overkill but Chri
s himself drew it up for me.- And Fred Hulen, or was it Hinde, anyway the
fluid design engineer on this list agreed.- Anyway, it seems to work for
me.=0A>> Jeff- =0A>> =0A>> =0A>> -----Original Message-----=0A>>> From:
Michel Therrien <mtherr@yahoo.com>=0A>>> Sent: Aug 24, 2011 8:41 PM=0A>>> T
o: "zenith601-list@matronics.com" <zenith601-list@matronics.com>=0A>>> Subj
ect: Re: Zenith601-List: Just a couple of questions=0A>>> =0A>>> --> Zenith
601-List message posted by: Michel Therrien <mtherr@yahoo.com>=0A>>> =0A>>>
Jeff, when i tested check valves in line with fuel pumps, i found there wo
uld be much more back flow into the opposite tank with a check valve than w
ithout... So i decided to deinstall them.=0A>>> =0A>>> Sent from my iPad=0A
>>> =0A>>> On Aug 24, 2011, at 7:40 PM, Jeff Davidson <jeffrey_davidson@ear
Davidson <jeffrey_davidson@earthlink.net>=0A>>>> =0A>>>> ... installed Fac
et pumps, 40105 I believe, next to both tanks.- After that per Chris Hein
tz' recommendation, are check valves to keep fuel from re-entering the tank
s.- ...=0A>>>> =0A>>>> =0A>>> =0A>>> =0A>>> =0A>>> =0A>>> =0A>> =0A>> =0A
- - - - - - - - - - - - - -Matt Dralle, List Adm
=====
Message 4
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Just a couple of questions |
Some Facet pumps have a built in check valve that still allows some back flow through
them, this is by design. It is intended to allow the fuel lines downstream
of the pump to depressurize after shut down.
There are also Facet pumps that are designed to prevent any back flow at all. These
are listed as having a built in anti-siphon valve or positive shut off.
Here is a link to the Facet- Purolator web page: http://tinyurl.com/252fhcb
--
Bryan Martin
N61BM, CH 601 XL,
RAM Subaru, Stratus re-drive.
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|