Today's Message Index:
----------------------
1. 11:03 AM - carb heat, filtration (Jerry Painter)
2. 12:52 PM - Re: carb heat, filtration (ggg6@att.net)
3. 01:13 PM - Re: carb heat, filtration (ggg6@att.net)
4. 01:14 PM - Re: carb heat, filtration (Jerry Painter)
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| Subject: | carb heat, filtration |
Hi Phil--
As others have said, the "funnels" are intended to provide heated air to
the
carburetor. Keep in mind that, like a -52, CJ's have a pressure carburet
or,
so "carb heat" isn't really a necessity, but alternate air is. It's
provided by the little flap on the back of the air box--not provided on
Yak-55's. I've had CJ's sans funnels and never had a problem with carb
icing, which is a non-issue any way with a pressure carb, though structur
al
icing/blockage could be, unless you're a blue sky guy like me. Get
stainless exhaust, too, if you haven't already, to prevent fires, a real
possibility with (guaranteed in time) perforated iron exhaust. The slip
joints are a big improvement over clamps, too.
Which leads to the air filter problem. The spark arrester and intake scr
een
do a lousy job of filtration. Surprising, given the typical unimproved a
nd
un-maintained airports the Russians and Chinese etc. use.
You probably know there are two CJ cowls, the early model with the intake
on
the bottom of the cowl and the later model with the intake on the front o
f
the cowl. Which do you have? In both cases air filtration is minimal at
best. You'll need to fabricate an adapter and maybe cut a foam or other
type filter material to fit. Well worth doing and usually neglected. I
don
t know of a commercially available filter kit--Doug?--and have never seen
a
sanitary installation--nor have I ever done it myself! Goolsby's noted
manifold pressure drop could be finessed with a diverter valve to unfilte
red
ram air--like some old Mooneys had--that could be opened in flight. Don'
t
forget to retain proper drainage of the air box to prevent fuel collectio
n
and subsequent carb fires. I understand the M-14R (?) has fuel injection
=2E
I'm a little surprised no one here in inventive America has come up with
an
injection system a la R-985 etc. Lots of opportunities for real
improvements.
I think cowl design is just about the weakest area on CJ's/-52's and begs
for improvement. Craig Payne has picked up a few knots with modest
revisions. I've often thought about changing the lower cowling mounts to
allow re-shaping the after/lower portion to snug up closer to the fuselag
e.
Po' boy that I am I've never been able to hold on to a CJ (or -52) long
enough to do the job! The venetian blind arrangement on Yak-52TW's is
terrible and entirely for cosmetic purposes, but some combination of cowl
flap and/or augmenters and possibly some intake restriction (spinner/dish
pan/iris?) should provide adequate (and probably improved) cooling while
greatly reducing drag. Seal up the cowl bottom, too. Removing the intak
e
vanes on a CJ is worth 10-15mph, but without them getting and maintaining
proper temps is a real problem, unless, maybe, you live in Phoenix or
Florida.
Jerry Painter
Wild Blue Aviation
425-876-0865wild.blue@verizon.net
http://mysite.verizon.net/res0cs5r/index.html
Message 2
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| Subject: | Re: carb heat, filtration |
Hi Guys.. Just a follow up comment on Icing in Acft. equipped with pressure Carbs.
Last year I was flying a navion in the L.A. basin early in the morning,
high humidity, Got a big time event of Carb. Icing, so the \thought that Pressure
Carbs. will not ice up is not alwaqys true.. Gary Gabbard CJ N22YK
-------------- Original message from "Jerry Painter" <wild.blue@verizon.net>: --------------
Hi Phil--
As others have said, the "funnels" are intended to provide heated air to the carburetor.
Keep in mind that, like a -52, CJ's have a pressure carburetor, so
"carb heat" isn't really a necessity, but alternate air is. It's provided by
the little flap on the back of the air box--not provided on Yak-55's. I've had
CJ's sans funnels and never had a problem with carb icing, which is a non-issue
any way with a pressure carb, though structural icing/blockage could be, unless
you're a blue sky guy like me. Get stainless exhaust, too, if you haven't
already, to prevent fires, a real possibility with (guaranteed in time) perforated
iron exhaust. The slip joints are a big improvement over clamps, too.
Which leads to the air filter problem. The spark arrester and intake screen do
a lousy job of filtration. Surprising, given the typical unimproved and un-maintained
airports the Russians and Chinese etc. use.
You probably know there are two CJ cowls, the early model with the intake on the
bottom of the cowl and the later model with the intake on the front of the cowl.
Which do you have? In both cases air filtration is minimal at best. You'll
need to fabricate an adapter and maybe cut a foam or other type filter material
to fit. Well worth doing and usually neglected. I don't know of a commercially
available filter kit--Doug?--and have never seen a sanitary installation--nor
have I ever done it myself! Goolsby's noted manifold pressure drop could
be finessed with a diverter valve to unfiltered ram air--like some old Mooneys
had--that could be opened in flight. Don't forget to retain proper drainage
of the air box to prevent fuel collection and subsequent carb fires. I understand
the M-14R (?) has fuel injection. I'm a little surprised no one here
in inventive America has come up with an injection system a la R-985 etc. Lots
of opportunities for real improvements.
I think cowl design is just about the weakest area on CJ's/-52's and begs for improvement.
Craig Payne has picked up a few knots with modest revisions. I've
often thought about changing the lower cowling mounts to allow re-shaping the
after/lower portion to snug up closer to the fuselage. Po' boy that I am I've
never been able to hold on to a CJ (or -52) long enough to do the job! The
venetian blind arrangement on Yak-52TW's is terrible and entirely for cosmetic
purposes, but some combination of cowl flap and/or augmenters and possibly some
intake restriction (spinner/dish pan/iris?) should provide adequate (and probably
improved) cooling while greatly reducing drag. Seal up the cowl bottom,
too. Removing the intake vanes on a CJ is worth 10-15mph, but without them
getting and maintaining proper temps is a real problem, unless, maybe, you live
in Phoenix or Florida.
Jerry Painter
Wild Blue Aviation
425-876-0865wild.blue@verizon.net
http://mysite.verizon.net/res0cs5r/index.html
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<DIV></DIV>Hi Guys.. Just a follow up comment on Icing in Acft. equipped
with pressure Carbs. Last year I was flying a navion in the L.A. basin early
in the morning, high humidity, Got a big time event of Carb. Icing, so the
\thought that Pressure Carbs. will not ice up is not alwaqys true..
Gary Gabbard CJ N22YK<BR>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px
solid">-------------- Original message from "Jerry Painter" <wild.blue@verizon.net>:
-------------- <BR><BR>
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<DIV><FONT face=Arial color=#000000><STRONG>Hi Phil--</STRONG></FONT></DIV>
<DIV><FONT face=Arial color=#000000><STRONG></STRONG></FONT> </DIV>
<DIV><FONT face=Arial color=#000000><STRONG>As others have said, the "funnels"
are intended to provide heated air to the carburetor. Keep in mind
that, like a -52, CJ's have a pressure carburetor, so "carb heat" isn't really
a necessity, but alternate air is. It's provided by the little flap on
the back of the air box--not provided on Yak-55's. I've had CJ's sans funnels
and never had a problem with carb icing, which is a non-issue any way with
a pressure carb, though structural icing/blockage could be, unless you're a
blue sky guy like me. Get stainless exhaust, too, if you haven't already,
to prevent fires, a real possibility with (guaranteed in time) perforated iron
exhaust. The slip joints are a big improvement over clamps, too.</STRONG></FONT></DIV>
<DIV><FONT face=Arial color=#000000><STRONG></STRONG></FONT> </DIV>
<DIV><FONT face=Arial color=#000000><STRONG>Which leads to the air filter problem.
The spark arrester and intake screen do a lousy job of filtration.
Surprising, given the typical unimproved and un-maintained airports
the Russians and Chinese etc. use. </STRONG></FONT></DIV>
<DIV><FONT face=Arial color=#000000><STRONG></STRONG></FONT> </DIV>
<DIV><FONT face=Arial color=#000000><STRONG>You probably know there are two CJ
cowls, the early model with the intake on the bottom of the cowl and the later
model with the intake on the front of the cowl. Which do you have? In both
cases air filtration is minimal at best. You'll need to fabricate
an adapter and maybe cut a foam or other type filter material to fit.
Well worth doing and usually neglected. I don't know of a commercially
available filter kit--Doug?--and have never seen a sanitary installation--nor
have I ever done it myself! Goolsby's noted manifold pressure drop could
be finessed with a diverter valve to unfiltered ram air--like some old Mooneys
had--that could be opened in flight. Don't forget to retain proper drainage
of the air box to prevent fuel collection and subsequent carb fires.
I understand the M-14R (?) has fuel injection. I'm a little surprised
no one here in inventive America has come up with an
injec
tion system a la R-985 etc. Lots of opportunities for real improvements.</STRONG></FONT></DIV>
<DIV><FONT face=Arial color=#000000><STRONG></STRONG></FONT> </DIV>
<DIV><FONT face=Arial color=#000000><STRONG>I think cowl design is just about the
weakest area on CJ's/-52's and begs for improvement. Craig Payne has
picked up a few knots with modest revisions. I've often thought about changing
the lower cowling mounts to allow re-shaping the after/lower portion to
snug up closer to the fuselage. Po' boy that I am I've never been able
to hold on to a CJ (or -52) long enough to do the job! The venetian blind
arrangement on Yak-52TW's is terrible and entirely for cosmetic purposes, but
some combination of cowl flap and/or augmenters and possibly some intake restriction
(spinner/dish pan/iris?) should provide adequate (and probably improved)
cooling while greatly reducing drag. Seal up the cowl bottom, too.
Removing the intake vanes on a CJ is worth 10-15mph, but without them getting
and maintaining proper temps is a real problem, unless, maybe, you live in
Phoenix or Florida.</STRONG></FONT></DIV>
<DIV> </DIV>
<DIV><IMG id=INCREDI_SIGIMG src="cid:DB086B4D-209D-4E15-AABB-6B28E998A938"></DIV>
<DIV>
<DIV><FONT face=Magneto size=5><FONT face=Arial color=#000000 size=3><STRONG>Jerry
Painter</STRONG></FONT></FONT></DIV>
<DIV><STRONG><FONT face=Arial></FONT></STRONG> </DIV>
<DIV><FONT face=Magneto color=#000080 size=5><EM><U><IMG style="WIDTH: 25px; HEIGHT:
26px" height=50 src="cid:F7BCAD2B-CB00-4AED-BBA3-CE7A0FFAA5F9" width=50></U></EM><FONT
color=#ffff00 size=6><U><EM>Wild Blue Aviation</EM></U></FONT><FONT
color=#ffff00> </FONT></FONT></DIV>
<DIV><FONT face=Arial color=#000000><STRONG>425-876-0865<IMG src="cid:62E4A43C-F4F3-4BBB-A15D-0E87C1E4D085"><U><FONT color=#0000ff><A href="mailto:wild.blue@verizon.net"><FONT color=#0000ff>wild.blue@verizon.net</FONT></A> <IMG src="cid:E262E9D0-6703-47F9-BC02-BE331604C9EB"></FONT></U></STRONG></FONT></DIV>
<DIV><STRONG><FONT color=#0000ff> </FONT></STRONG><A href="http://mysite.verizon.net/res0cs5r/index.html"><FONT face=Arial color=#0000ff><STRONG>http://mysite.verizon.net/res0cs5r/index.html</STRONG></FONT></A><FONT face=Arial color=#0000ff><STRONG> </STRONG></FONT></DIV>
<DIV><STRONG><FONT face=Arial color=#0000ff></FONT></STRONG> </DIV></DIV></TD></TR>
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| Subject: | Re: carb heat, filtration |
Icing and Pressure Carbs.
Hi Guys.. Just a follow up comment on Icing in Acft. equipped with pressure Carbs.
Last year I was flying a navion in the L.A. basin early in the morning,
high humidity, Got a big time event of Carb. Icing, so the \thought that Pressure
Carbs. will not ice up is not alwaqys true.. Gary Gabbard CJ N22YK
-------------- Original message from "Jerry Painter" <wild.blue@verizon.net>: --------------
Hi Phil--
As others have said, the "funnels" are intended to provide heated air to the carburetor.
Keep in mind that, like a -52, CJ's have a pressure carburetor, so
"carb heat" isn't really a necessity, but alternate air is. It's provided by
the little flap on the back of the air box--not provided on Yak-55's. I've had
CJ's sans funnels and never had a problem with carb icing, which is a non-issue
any way with a pressure carb, though structural icing/blockage could be, unless
you're a blue sky guy like me. Get stainless exhaust, too, if you haven't
already, to prevent fires, a real possibility with (guaranteed in time) perforated
iron exhaust. The slip joints are a big improvement over clamps, too.
Which leads to the air filter problem. The spark arrester and intake screen do
a lousy job of filtration. Surprising, given the typical unimproved and un-maintained
airports the Russians and Chinese etc. use.
You probably know there are two CJ cowls, the early model with the intake on the
bottom of the cowl and the later model with the intake on the front of the cowl.
Which do you have? In both cases air filtration is minimal at best. You'll
need to fabricate an adapter and maybe cut a foam or other type filter material
to fit. Well worth doing and usually neglected. I don't know of a commercially
available filter kit--Doug?--and have never seen a sanitary installation--nor
have I ever done it myself! Goolsby's noted manifold pressure drop could
be finessed with a diverter valve to unfiltered ram air--like some old Mooneys
had--that could be opened in flight. Don't forget to retain proper drainage
of the air box to prevent fuel collection and subsequent carb fires. I understand
the M-14R (?) has fuel injection. I'm a little surprised no one here
in inventive America has come up with an injec tion system a la R-985 etc.
Lots of opportunities for real improvements.
I think cowl design is just about the weakest area on CJ's/-52's and begs for improvement.
Craig Payne has picked up a few knots with modest revisions. I've
often thought about changing the lower cowling mounts to allow re-shaping the
after/lower portion to snug up closer to the fuselage. Po' boy that I am I've
never been able to hold on to a CJ (or -52) long enough to do the job! The
venetian blind arrangement on Yak-52TW's is terrible and entirely for cosmetic
purposes, but some combination of cowl flap and/or augmenters and possibly some
intake restriction (spinner/dish pan/iris?) should provide adequate (and probably
improved) cooling while greatly reducing drag. Seal up the cowl bottom,
too. Removing the intake vanes on a CJ is worth 10-15mph, but without them
getting and maintaining proper temps is a real problem, unless, maybe, you live
in Phoenix or Florida.
Jerry Painter
Wild Blue Aviation
425-876-0865wild.blue@verizon.net
http://mysite.verizon.net/res0cs5r/index.html
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<DIV></DIV>Icing and Pressure Carbs.<BR>
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<DIV></DIV>Hi Guys.. Just a follow up comment on Icing in Acft. equipped
with pressure Carbs. Last year I was flying a navion in the L.A. basin early
in the morning, high humidity, Got a big time event of Carb. Icing, so the
\thought that Pressure Carbs. will not ice up is not alwaqys true..
Gary Gabbard CJ N22YK<BR>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #1010ff 2px
solid">-------------- Original message from "Jerry Painter" <wild.blue@verizon.net>:
-------------- <BR><BR>
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<DIV><FONT face=Arial color=#000000><STRONG>Hi Phil--</STRONG></FONT></DIV>
<DIV><FONT face=Arial color=#000000><STRONG></STRONG></FONT> </DIV>
<DIV><FONT face=Arial color=#000000><STRONG>As others have said, the "funnels"
are intended to provide heated air to the carburetor. Keep in mind
that, like a -52, CJ's have a pressure carburetor, so "carb heat" isn't really
a necessity, but alternate air is. It's provided by the little flap on
the back of the air box--not provided on Yak-55's. I've had CJ's sans funnels
and never had a problem with carb icing, which is a non-issue any way with
a pressure carb, though structural icing/blockage could be, unless you're a
blue sky guy like me. Get stainless exhaust, too, if you haven't already,
to prevent fires, a real possibility with (guaranteed in time) perforated iron
exhaust. The slip joints are a big improvement over clamps, too.</STRONG></FONT></DIV>
<DIV><FONT face=Arial color=#000000><STRONG></STRONG></FONT> </DIV>
<DIV><FONT face=Arial color=#000000><STRONG>Which leads to the air filter problem.
The spark arrester and intake screen do a lousy job of filtration.
Surprising, given the typical unimproved and un-maintained airports
the Russians and Chinese etc. use. </STRONG></FONT></DIV>
<DIV><FONT face=Arial color=#000000><STRONG></STRONG></FONT> </DIV>
<DIV><FONT face=Arial color=#000000><STRONG>You probably know there are two CJ
cowls, the early model with the intake on the bottom of the cowl and the later
model with the intake on the front of the cowl. Which do you have? In both
cases air filtration is minimal at best. You'll need to fabricate
an adapter and maybe cut a foam or other type filter material to fit.
Well worth doing and usually neglected. I don't know of a commercially
available filter kit--Doug?--and have never seen a sanitary installation--nor
have I ever done it myself! Goolsby's noted manifold pressure drop could
be finessed with a diverter valve to unfiltered ram air--like some old Mooneys
had--that could be opened in flight. Don't forget to retain proper drainage
of the air box to prevent fuel collection and subsequent carb fires.
I understand the M-14R (?) has fuel injection. I'm a little surprised
no one here in inventive America has come up with an
injec
tion system a la R-985 etc. Lots of opportunities for real improvements.</STRONG></FONT></DIV>
<DIV><FONT face=Arial color=#000000><STRONG></STRONG></FONT> </DIV>
<DIV><FONT face=Arial color=#000000><STRONG>I think cowl design is just about the
weakest area on CJ's/-52's and begs for improvement. Craig Payne has
picked up a few knots with modest revisions. I've often thought about changing
the lower cowling mounts to allow re-shaping the after/lower portion to
snug up closer to the fuselage. Po' boy that I am I've never been able
to hold on to a CJ (or -52) long enough to do the job! The venetian blind
arrangement on Yak-52TW's is terrible and entirely for cosmetic purposes, but
some combination of cowl flap and/or augmenters and possibly some intake restriction
(spinner/dish pan/iris?) should provide adequate (and probably improved)
cooling while greatly reducing drag. Seal up the cowl bottom, too.
Removing the intake vanes on a CJ is worth 10-15mph, but without them getting
and maintaining proper temps is a real problem, unless, maybe, you live in
Phoenix or Florida.</STRONG></FONT></DIV>
<DIV> </DIV>
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<DIV>
<DIV><FONT face=Magneto size=5><FONT face=Arial color=#000000 size=3><STRONG>Jerry
Painter</STRONG></FONT></FONT></DIV>
<DIV><STRONG><FONT face=Arial></FONT></STRONG> </DIV>
<DIV><FONT face=Magneto color=#000080 size=5><EM><U><IMG style="WIDTH: 25px; HEIGHT:
26px" height=50 src="cid:F7BCAD2B-CB00-4AED-BBA3-CE7A0FFAA5F9" width=50></U></EM><FONT
color=#ffff00 size=6><U><EM>Wild Blue Aviation</EM></U></FONT><FONT
color=#ffff00> </FONT></FONT></DIV>
<DIV><FONT face=Arial color=#000000><STRONG>425-876-0865<IMG src="cid:62E4A43C-F4F3-4BBB-A15D-0E87C1E4D085"><U><FONT color=#0000ff><A href="mailto:wild.blue@verizon.net"><FONT color=#0000ff>wild.blue@verizon.net</FONT></A> <IMG src="cid:E262E9D0-6703-47F9-BC02-BE331604C9EB"></FONT></U></STRONG></FONT></DIV>
<DIV><STRONG><FONT color=#0000ff> </FONT></STRONG><A href="http://mysite.verizon.net/res0cs5r/index.html"><FONT face=Arial color=#0000ff><STRONG>http://mysite.verizon.net/res0cs5r/index.html</STRONG></FONT></A><FONT face=Arial color=#0000ff><STRONG> </STRONG></FONT></DIV>
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| Subject: | Re: carb heat, filtration |
Fiberglass is probably heavier than aluminum, but carbon fiber would be
considerably lighter and easy to make compound curves. Lightspeed would
be
a big improvement. Go get 'em!
JP
-Original Message-------
From: PSalter@aol.com
Subject: Re: carb heat, filtration
Jerry,
Where do you find time to write your informative, interesting and long
emails. I appreciate and welcome your opinions and ideas.
I ordered a stainless exhaust from Doug and will take delivery when he ha
s a
complete kit available. My cowl has the front intake. I have the foam
brackett filter material I will look at the setup and see if I can figure
something out. It seems a fiberglass duct would work well with the cowl
intake.
I would like to have a new cowl built out of fiberglass. I have a friend
building a Cozy a couple of hangers down that I would ask for help. I wou
ld
prefer more of a Bonanza style cowl that could be opened for preflight wi
th
ease. Also, the vibration would be less of a problem with fiberglass as i
t
would be much lighter. A friend in Houston is the constructor of the MX2.
Last weekend I picked up the entire cowl and was shocked how light the
carbon fiber is. I knew it was light, but shocked how light. Below is a
picture of the MX2. The first plane went to a Red Bull race in Abu Dabi (
or
something like that) and was flown by Mike Goulian(or something like that
).
I am surprised we are not all using Klaus Savier's (Lightspeed CDI) style
of
electronic ignition along with some style of fuel injection. Efficiency
would jump along with reliability and a more power.
Thanks again!
Phil
In a message dated 6/11/2006 1:00:20 P.M. Central Standard Time, wild
blue@verizon.net writes:
Hi Phil--
As others have said, the "funnels" are intended to provide heated air to
the
carburetor. Keep in mind that, like a -52, CJ's have a pressure carburet
or,
so "carb heat" isn't really a necessity, but alternate air is. It's
provided by the little flap on the back of the air box--not provided on
Yak-55's. I've had CJ's sans funnels and never had a problem with carb
icing, which is a non-issue any way with a pressure carb, though structur
al
icing/blockage could be, unless you're a blue sky guy like me. Get
stainless exhaust, too, if you haven't already, to prevent fires, a real
possibility with (guaranteed in time) perforated iron exhaust. The slip
joints are a big improvement over clamps, too.
Which leads to the air filter problem. The spark arrester and intake scr
een
do a lousy job of filtration. Surprising, given the typical unimproved a
nd
un-maintained airports the Russians and Chinese etc. use.
You probably know there are two CJ cowls, the early model with the intake
on
the bottom of the cowl and the later model with the intake on the front o
f
the cowl. Which do you have? In both cases air filtration is minimal at
best. You'll need to fabricate an adapter and maybe cut a foam or other
type filter material to fit. Well worth doing and usually neglected. I
don
t know of a commercially available filter kit--Doug?--and have never seen
a
sanitary installation--nor have I ever done it myself! Goolsby's noted
manifold pressure drop could be finessed with a diverter valve to unfilte
red
ram air--like some old Mooneys had--that could be opened in flight. Don'
t
forget to retain proper drainage of the air box to prevent fuel collectio
n
and subsequent carb fires. I understand the M-14R (?) has fuel injection
=2E
I'm a little surprised no one here in inventive America has come up with
an
injection system a la R-985 etc. Lots of opportunities for real
improvements.
I think cowl design is just about the weakest area on CJ's/-52's and begs
for improvement. Craig Payne has picked up a few knots with modest
revisions. I've often thought about changing the lower cowling mounts to
allow re-shaping the after/lower portion to snug up closer to the fuselag
e.
Po' boy that I am I've never been able to hold on to a CJ (or -52) long
enough to do the job! The venetian blind arrangement on Yak-52TW's is
terrible and entirely for cosmetic purposes, but some combination of cowl
flap and/or augmenters and possibly some intake restriction (spinner/dish
pan/iris?) should provide adequate (and probably improved) cooling while
greatly reducing drag. Seal up the cowl bottom, too. Removing the intak
e
vanes on a CJ is worth 10-15mph, but without them getting and maintaining
proper temps is a real problem, unless, maybe, you live in Phoenix or
Florida.
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