pitts_pilot(at)bellsouth.
Guest
|
 Posted: Fri Feb 02, 2007 1:41 pm Post subject: purge valves |
 |
|
Dan Checkoway wrote:
| Quote: |
You don't have AFP injection on your Mooney. I should have clarified...
If you have AFP injection (i.e. an FM-200 servo), then leaning the
mixture all the way to the "ICO" position doesn't actually stop fuel
flow completely -- by design.
|
This is where I have a problem. What benefit does having a leaky ICO
provide??? Is this in the category of 'unadvertised benefit'??? Why
can't the servo be designed to shut the fuel off at ICO???? Any one
know???? When you use the purge valve, how much fuel comes out each
time you use it???
Linn ..... struggling to understand.
do not archive
| Quote: | Fuel still flows even when the mixture is back to ICO stop.
I'm sitting here with the AFP manual right in front of me. On page 21
of Revision B it says:
"When "ICO" is against the plastic stop, the fuel flow is shut off to
the engine. There is approximately 1.0 to 3.0 PPH leakage in this
position."
And then below that in big bold it says:
"NOTE: The manual mixture is not intended to be used as a fuel shut
valve. If the fuel supply is near or above the level of the injector
nozzles fuel will seep into the engine, or seep out the injector
nozzle vents. A zero leak fuel shut off valve must be used on these
installations."
Granted, we aren't talking about high-wing setups here, but in
principle we need to consider this effect.
The purge valve is what is responsible for completely cutting off the
flow of fuel to the cylinders. If you remove the purge valve from an
AFP system, you have no way to completely stop the flow of fuel unless
you literally cut off fuel supply at the fuel selector valve.
Note also that on page 32 of Revision B, where it talks about
installing the purge valve, it clearly says:
"Lock wire all hardware. Make sure to lock wire the stop screw."
I hope this clarifies what I meant, and I'm sure Don Rivera at AFP
will correct me if I'm wrong.
)_( Dan
RV-7 N714D
www.rvproject.com
|
| | - The Matronics RV-List Email Forum - | | | Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:
http://www.matronics.com/Navigator?RV-List |
|
|
|
Get Email Distribution Too!
FAQ
Search
Memberlist
Usergroups
Register
Profile
Log in to check your private messages
Log in
