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John A. Landry
Guest
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 Posted: Mon Mar 07, 2005 6:02 pm Post subject: Electric Carb Heaters? |
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|
Greetings,
Does anyone have any experience (good or bad) with the electric carb
heaters that used to be sold to prevent carb icing on Bing side carbs?
The reason I ask is because I believe I had a couple of brief encounters
with carb icing on my dual carb Rotax 503 DCDI a couple of weeks ago when
flying in conditions of severe carb icing. The air temp was 40-45 degrees
and high humidity (visible in the air). Needless to say I didn't like
being scared like that and I don't care to experience it again.
As a result, I'm contemplating machining my own little adapters to press on
to the intake side of the carbs, each of which will hold a 30 watt
cartridge heater to be powered directly off the AC currant from alternator.
The pair of cartridge heaters should draw only 2.5 amps or less from the
alternator. How much heat the cartridge heaters will actually put out on
24 to 90 volts from the Rotax alternator is an unknown at this point.
Regarding carb ice...
Interestingly, I've never experienced any sort of carb icing symptom in
prior years when using premixed oil/fuel in my engine... and I flew in all
sorts of temperature and dew point conditions (short of flying in pouring
rain... which I did *once* and will never do that again either). The
flight where I experienced icing was only my second flight after upgrading
my 503 with an oil-injection system. The first flight since installing the
oil-injection system was in 35 degree air temps and low humidity. As one
would expect, no icing symptoms were experienced during that flight.
Can it really be true that oil in the fuel helps prevent carb icing? Based
on my very limited experience, it would seem so.
Anyway, I want something to guard against carb icing, and warming the carb
bodies electrically seems by far the simplest and fastest way to get there
(verses building a system to heat the intake air).
Thanks,
John L.
Shoreline, WA
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Jean-Paul Roy
Guest
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| Posted: Mon Mar 07, 2005 11:17 pm Post subject: Re: Electric Carb Heaters? |
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Hello John, I don't quite believe that oil in the fuel helps prevent carb
icing. But I do believe that the oil prevents icing from sticking on the
carb walls.
Just an opinion
Jean-Paul
"John A. Landry" <gyroSPAM-FREEpilot001 (AT) earthlink (DOT) net> wrote
| Quote: | Greetings,
Does anyone have any experience (good or bad) with the electric carb
heaters that used to be sold to prevent carb icing on Bing side carbs?
The reason I ask is because I believe I had a couple of brief encounters
with carb icing on my dual carb Rotax 503 DCDI a couple of weeks ago when
flying in conditions of severe carb icing. The air temp was 40-45 degrees
and high humidity (visible in the air). Needless to say I didn't like
being scared like that and I don't care to experience it again.
As a result, I'm contemplating machining my own little adapters to press
on
to the intake side of the carbs, each of which will hold a 30 watt
cartridge heater to be powered directly off the AC currant from
alternator.
The pair of cartridge heaters should draw only 2.5 amps or less from the
alternator. How much heat the cartridge heaters will actually put out on
24 to 90 volts from the Rotax alternator is an unknown at this point.
Regarding carb ice...
Interestingly, I've never experienced any sort of carb icing symptom in
prior years when using premixed oil/fuel in my engine... and I flew in all
sorts of temperature and dew point conditions (short of flying in pouring
rain... which I did *once* and will never do that again either). The
flight where I experienced icing was only my second flight after upgrading
my 503 with an oil-injection system. The first flight since installing
the
oil-injection system was in 35 degree air temps and low humidity. As one
would expect, no icing symptoms were experienced during that flight.
Can it really be true that oil in the fuel helps prevent carb icing?
Based
on my very limited experience, it would seem so.
Anyway, I want something to guard against carb icing, and warming the carb
bodies electrically seems by far the simplest and fastest way to get there
(verses building a system to heat the intake air).
Thanks,
John L.
Shoreline, WA
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John Rockrohr
Guest
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| Posted: Mon Mar 07, 2005 11:48 pm Post subject: Re: Electric Carb Heaters? |
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|
HI John,
Here's some info, not sure if it's good or not. Goto Ebay and do a
search for "bing 54 carb heat", and an offer for plans to build carb heater
for about $30 should come up. I haven't ordered the plans yet, but I spoke
with the seller who assured me the parts were readily available for about
$100 from places like Wag-Aero, CPS, etc. If the offer is legit it sounds
like $130 will get them built.
John Rockrohr
"John A. Landry" <gyroSPAM-FREEpilot001 (AT) earthlink (DOT) net> wrote
| Quote: | Greetings,
Does anyone have any experience (good or bad) with the electric carb
heaters that used to be sold to prevent carb icing on Bing side carbs?
The reason I ask is because I believe I had a couple of brief encounters
with carb icing on my dual carb Rotax 503 DCDI a couple of weeks ago when
flying in conditions of severe carb icing. The air temp was 40-45 degrees
and high humidity (visible in the air). Needless to say I didn't like
being scared like that and I don't care to experience it again.
As a result, I'm contemplating machining my own little adapters to press
on
to the intake side of the carbs, each of which will hold a 30 watt
cartridge heater to be powered directly off the AC currant from
alternator.
The pair of cartridge heaters should draw only 2.5 amps or less from the
alternator. How much heat the cartridge heaters will actually put out on
24 to 90 volts from the Rotax alternator is an unknown at this point.
Regarding carb ice...
Interestingly, I've never experienced any sort of carb icing symptom in
prior years when using premixed oil/fuel in my engine... and I flew in all
sorts of temperature and dew point conditions (short of flying in pouring
rain... which I did *once* and will never do that again either). The
flight where I experienced icing was only my second flight after upgrading
my 503 with an oil-injection system. The first flight since installing
the
oil-injection system was in 35 degree air temps and low humidity. As one
would expect, no icing symptoms were experienced during that flight.
Can it really be true that oil in the fuel helps prevent carb icing?
Based
on my very limited experience, it would seem so.
Anyway, I want something to guard against carb icing, and warming the carb
bodies electrically seems by far the simplest and fastest way to get there
(verses building a system to heat the intake air).
Thanks,
John L.
Shoreline, WA
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John A. Landry
Guest
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| Posted: Tue Mar 08, 2005 7:41 pm Post subject: Re: Electric Carb Heaters? |
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|
On Mon, 7 Mar 2005 17:48:31 -0600, in rec.aviation.ultralight, John
Rockrohr said:
| Quote: | Here's some info, not sure if it's good or not. Goto Ebay and do a
search for "bing 54 carb heat", and an offer for plans to build carb heater
for about $30 should come up. I haven't ordered the plans yet, but I spoke
with the seller who assured me the parts were readily available for about
$100 from places like Wag-Aero, CPS, etc. If the offer is legit it sounds
like $130 will get them built.
|
Hi John,
Thanks for the pointer.
Yes... I've seen the guy's plans on eBay. He apparently uses a bolt
together approach, which is a logical method of course.
However, since I have my own hobby machine shop in my garage, I intend to
instead machine my adapters out of solid pieces of 6061 aluminum, and then
*press* them on permanently to the carb inlets. They'll be more compact
and less noticeable this way. I've already sketched out the design and I
hope to make them this coming weekend.
In the mean time, I've already bought 2-1/2" long x 1/4" diameter 30 watt /
120 volt cartridge heaters from www.mcmaster.com, and will press them into
the adapters right up under the carb inlet.
Best regards,
John L.
Shoreline, WA
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sleepy6
Guest
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| Posted: Tue Mar 08, 2005 9:14 pm Post subject: Re: Electric Carb Heaters? |
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In article <pkvr21h7ro7pkohdh80m5ucs6tdi8da85r (AT) 4ax (DOT) com>,
[email]gyroSPAM-FREEpilot001 (AT) earthlink (DOT) net[/email] says...
| Quote: |
On Mon, 7 Mar 2005 17:48:31 -0600, in rec.aviation.ultralight, John
Rockrohr said:
Here's some info, not sure if it's good or not. Goto Ebay and do
a
search for "bing 54 carb heat", and an offer for plans to build carb
heater
for about $30 should come up. I haven't ordered the plans yet, but I
spoke
with the seller who assured me the parts were readily available for a
bout
$100 from places like Wag-Aero, CPS, etc. If the offer is legit it s
ounds
like $130 will get them built.
Hi John,
Thanks for the pointer.
Yes... I've seen the guy's plans on eBay. He apparently uses a bolt
together approach, which is a logical method of course.
However, since I have my own hobby machine shop in my garage, I intend
to
instead machine my adapters out of solid pieces of 6061 aluminum, and
then
*press* them on permanently to the carb inlets. They'll be more compa
ct
and less noticeable this way. I've already sketched out the design an
d I
hope to make them this coming weekend.
In the mean time, I've already bought 2-1/2" long x 1/4" diameter 30 w
att /
120 volt cartridge heaters from www.mcmaster.com, and will press them
into
the adapters right up under the carb inlet.
Best regards,
John L.
Shoreline, WA
|
120 volt?
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John A. Landry
Guest
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| Posted: Wed Mar 09, 2005 12:04 am Post subject: Re: Electric Carb Heaters? |
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On Tue, 08 Mar 2005 21:14:08 GMT, in rec.aviation.ultralight, sleepy6 said:
120 volts is the maximum the cartridge heater is rated to continuously
withstand. There's no reason why less voltage can't be applied to it.
According to the tech literature from California Power Systems, the modern
Rotax 503 alternator 503 puts out from about 24 volts at idle to 90+ volts
at 6800 rpm.
Best regards,
John L.
Shoreline, WA
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sleepy6
Guest
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| Posted: Wed Mar 09, 2005 12:37 am Post subject: Re: Electric Carb Heaters? |
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In article <85fs21dcdghtj1d5ag9otnotkgge2hon0f (AT) 4ax (DOT) com>,
[email]gyroSPAM-TRAP-HEREpilot001 (AT) earthlink (DOT) net[/email] says...
| Quote: |
On Tue, 08 Mar 2005 21:14:08 GMT, in rec.aviation.ultralight, sleepy6
said:
120 volt?
120 volts is the maximum the cartridge heater is rated to continuously
withstand. There's no reason why less voltage can't be applied to it.
According to the tech literature from California Power Systems, the mo
dern
Rotax 503 alternator 503 puts out from about 24 volts at idle to 90+ v
olts
at 6800 rpm.
Best regards,
John L.
Shoreline, WA
|
Thats at no load. The voltage drops rapidly even under a light load.
You probably will not get enough voltage to push much current through
that resistance. The end result will be very little heat.
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Mark Smith
Guest
|
| Posted: Wed Mar 09, 2005 1:09 am Post subject: Re: Electric Carb Heaters? |
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sleepy6 wrote:
| Quote: |
In article <pkvr21h7ro7pkohdh80m5ucs6tdi8da85r (AT) 4ax (DOT) com>,
[email]gyroSPAM-FREEpilot001 (AT) earthlink (DOT) net[/email] says...
On Mon, 7 Mar 2005 17:48:31 -0600, in rec.aviation.ultralight, John
Rockrohr said:
Here's some info, not sure if it's good or not. Goto Ebay and do
a
search for "bing 54 carb heat", and an offer for plans to build carb
heater
for about $30 should come up. I haven't ordered the plans yet, but I
spoke
with the seller who assured me the parts were readily available for a
bout
$100 from places like Wag-Aero, CPS, etc. If the offer is legit it s
ounds
like $130 will get them built.
Hi John,
Thanks for the pointer.
Yes... I've seen the guy's plans on eBay. He apparently uses a bolt
together approach, which is a logical method of course.
However, since I have my own hobby machine shop in my garage, I intend
to
instead machine my adapters out of solid pieces of 6061 aluminum, and
then
*press* them on permanently to the carb inlets. They'll be more compa
ct
and less noticeable this way. I've already sketched out the design an
d I
hope to make them this coming weekend.
In the mean time, I've already bought 2-1/2" long x 1/4" diameter 30 w
att /
120 volt cartridge heaters from www.mcmaster.com, and will press them
into
the adapters right up under the carb inlet.
Best regards,
John L.
Shoreline, WA
120 volt?
|
You think maybe he shoulda bought the plans ?
--
Mark Smith
Tri-State Kite Sales
1121 N Locust St
Mt Vernon, IN 47620
1-812-838-6351
http://www.trikite.com
mailto:mark (AT) trikite (DOT) com
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John A. Landry
Guest
|
| Posted: Wed Mar 09, 2005 4:06 pm Post subject: Re: Electric Carb Heaters? |
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|
On Wed, 09 Mar 2005 00:37:01 GMT, in rec.aviation.ultralight, sleepy6 said:
| Quote: | Thats at no load. The voltage drops rapidly even under a light load.
You probably will not get enough voltage to push much current through
that resistance. The end result will be very little heat.
|
Of course the voltage will drop under load!
However, as long as the AC voltage drop isn't significant enough to affect
rectified DC current downstream (as in below 15-16 volts), it shouldn't a
problem.
I'll test the circuit this weekend (heat output of the cartridges and the
voltage drop of both AC and rectified DC circuits) and report the results
here.
Regards,
John L.
Shoreline, WA
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Q
Guest
|
| Posted: Wed Mar 09, 2005 5:18 pm Post subject: Re: Electric Carb Heaters? |
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If more voltage is needed it would be easy enough to add a small
transformer to get whatever voltage is necessary.
Q
John A. Landry wrote:
| Quote: | On Wed, 09 Mar 2005 00:37:01 GMT, in rec.aviation.ultralight, sleepy6 said:
Thats at no load. The voltage drops rapidly even under a light load.
You probably will not get enough voltage to push much current through
that resistance. The end result will be very little heat.
Of course the voltage will drop under load!
However, as long as the AC voltage drop isn't significant enough to affect
rectified DC current downstream (as in below 15-16 volts), it shouldn't a
problem.
I'll test the circuit this weekend (heat output of the cartridges and the
voltage drop of both AC and rectified DC circuits) and report the results
here.
Regards,
John L.
Shoreline, WA
|
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| Back to top |
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Smitty
Guest
|
| Posted: Wed Mar 09, 2005 5:47 pm Post subject: Re: Electric Carb Heaters? |
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In article <376u21tod8u7futa8uu3r8siqicoqk51i0 (AT) 4ax (DOT) com>,
John A. Landry <gyroSPAM-SUCKSpilot001 (AT) earthlink (DOT) net> wrote:
| Quote: | On Wed, 09 Mar 2005 00:37:01 GMT, in rec.aviation.ultralight, sleepy6 said:
Thats at no load. The voltage drops rapidly even under a light load.
You probably will not get enough voltage to push much current through
that resistance. The end result will be very little heat.
Of course the voltage will drop under load!
However, as long as the AC voltage drop isn't significant enough to affect
rectified DC current downstream (as in below 15-16 volts), it shouldn't a
problem.
I'll test the circuit this weekend (heat output of the cartridges and the
voltage drop of both AC and rectified DC circuits) and report the results
here.
Regards,
John L.
Shoreline, WA
|
Don't forget that power doesn't drop proportionally to voltage, it drops
proportionally to the square of voltage (W = V*V/R.) Putting 85 volts
through a heater designed for 120 will cut your heating power in half.
If the loaded alternator puts out only 60 volts, you'll cut the heat
output of those cartridges to 25%. But hell, who's to say that isn't
enough? Let us know what happens...
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Mark Smith
Guest
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| Posted: Wed Mar 09, 2005 6:00 pm Post subject: Re: Electric Carb Heaters? |
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Smitty wrote:
| Quote: |
In article <376u21tod8u7futa8uu3r8siqicoqk51i0 (AT) 4ax (DOT) com>,
John A. Landry <gyroSPAM-SUCKSpilot001 (AT) earthlink (DOT) net> wrote:
On Wed, 09 Mar 2005 00:37:01 GMT, in rec.aviation.ultralight, sleepy6 said:
Thats at no load. The voltage drops rapidly even under a light load.
You probably will not get enough voltage to push much current through
that resistance. The end result will be very little heat.
Of course the voltage will drop under load!
However, as long as the AC voltage drop isn't significant enough to affect
rectified DC current downstream (as in below 15-16 volts), it shouldn't a
problem.
I'll test the circuit this weekend (heat output of the cartridges and the
voltage drop of both AC and rectified DC circuits) and report the results
here.
Regards,
John L.
Shoreline, WA
Don't forget that power doesn't drop proportionally to voltage, it drops
proportionally to the square of voltage (W = V*V/R.) Putting 85 volts
through a heater designed for 120 will cut your heating power in half.
If the loaded alternator puts out only 60 volts, you'll cut the heat
output of those cartridges to 25%. But hell, who's to say that isn't
enough? Let us know what happens...
|
The alternator is rated by Rotax at about 150 watts.
Use as you like but the current at 15 volts is about 6 amps at best.
I like the idea of the 120 volts !
--
Mark Smith
Tri-State Kite Sales
1121 N Locust St
Mt Vernon, IN 47620
1-812-838-6351
http://www.trikite.com
mailto:mark (AT) trikite (DOT) com
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Jan Nademlejnsky
Guest
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| Posted: Thu Mar 10, 2005 6:26 am Post subject: Re: Electric Carb Heaters? |
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|
I am very experienced "Rotax Flyer" with iced up carburetors. I fly (try to fly) in the winter, but the carburetor icing drives me crazy. When I was flying single cylinder Rotax 272 or Yamaha 286 it was easy. I carried on board hair dryer. As soon as I heard the engine coughing, I landed, removed carb, run to nearest car plugging, plugged in hair dryer *), melted ice, installed carb and flew again. This is not as easy now, with dual carb on my Rotax 582. The last time I flew, I did not feel or hear anything, but when I removed the air filter I saw the carb full of ice. It is scary and I do not know how the 582 would behave. Would it suddenly quit or is there any warning. I always wondered how people do it to fly in the winter with 2 stroke above hostile territory without fear the engine would quit.
*) I live in Canada, where everybody has outdoor car plug to keep car from freezing (-45C).
Jan Nademlejnsky
http://members.shaw.ca/jannadem/home.htm
"John A. Landry" <gyroSPAM-FREEpilot001 (AT) earthlink (DOT) net> wrote
| Quote: | Greetings,
Does anyone have any experience (good or bad) with the electric carb
heaters that used to be sold to prevent carb icing on Bing side carbs?
The reason I ask is because I believe I had a couple of brief encounters
with carb icing on my dual carb Rotax 503 DCDI a couple of weeks ago when
flying in conditions of severe carb icing. The air temp was 40-45 degrees
and high humidity (visible in the air). Needless to say I didn't like
being scared like that and I don't care to experience it again.
As a result, I'm contemplating machining my own little adapters to press on
to the intake side of the carbs, each of which will hold a 30 watt
cartridge heater to be powered directly off the AC currant from alternator.
The pair of cartridge heaters should draw only 2.5 amps or less from the
alternator. How much heat the cartridge heaters will actually put out on
24 to 90 volts from the Rotax alternator is an unknown at this point.
Regarding carb ice...
Interestingly, I've never experienced any sort of carb icing symptom in
prior years when using premixed oil/fuel in my engine... and I flew in all
sorts of temperature and dew point conditions (short of flying in pouring
rain... which I did *once* and will never do that again either). The
flight where I experienced icing was only my second flight after upgrading
my 503 with an oil-injection system. The first flight since installing the
oil-injection system was in 35 degree air temps and low humidity. As one
would expect, no icing symptoms were experienced during that flight.
Can it really be true that oil in the fuel helps prevent carb icing? Based
on my very limited experience, it would seem so.
Anyway, I want something to guard against carb icing, and warming the carb
bodies electrically seems by far the simplest and fastest way to get there
(verses building a system to heat the intake air).
Thanks,
John L.
Shoreline, WA
|
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| Back to top |
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sleepy6
Guest
|
| Posted: Thu Mar 10, 2005 11:47 am Post subject: Re: Electric Carb Heaters? |
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|
Good idea if he can determine what voltage the altenator actually puts
out under whatever his normal load might be. I did some experiments
way back when and the AC voltage swings all over the place depending on
rpm and load. A 120 volt to 24 VAC at 2 or 3 amp transformer hooked up
backwards might be a good place to start experimenting but that's just
a guess.
In article <398petF60t21cU1 (AT) individual (DOT) net>,
[email]hugemothnospam (AT) access4less (DOT) net[/email] says...
| Quote: |
If more voltage is needed it would be easy enough to add a small
transformer to get whatever voltage is necessary.
Q
John A. Landry wrote:
On Wed, 09 Mar 2005 00:37:01 GMT, in rec.aviation.ultralight, sleepy
6 said:
Thats at no load. The voltage drops rapidly even under a light load
.
You probably will not get enough voltage to push much current throug
h
that resistance. The end result will be very little heat.
Of course the voltage will drop under load!
However, as long as the AC voltage drop isn't significant enough to
affect
rectified DC current downstream (as in below 15-16 volts), it should
n't a
problem.
I'll test the circuit this weekend (heat output of the cartridges an
d the
voltage drop of both AC and rectified DC circuits) and report the re
sults
here.
Regards,
John L.
Shoreline, WA
|
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| Back to top |
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Q
Guest
|
| Posted: Thu Mar 10, 2005 1:28 pm Post subject: Re: Electric Carb Heaters? |
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|
Jan,
I fly in the winter here in the high desert of Central Oregon and have
experienced carb icing many times on my 582. First thing is that I don't
fly over hostile terrain because I've been forced to land several times
to let the ice melt. Only once did I have to land in a place that was
too small to take off again, and that was a real hassle.
So far I have only had carb ice problems when the temp was below 35 F
and there was fog within a couple miles. First thing I notice is my EGTs
going down to below 1000 F, then below 900, and I know it's starting to
ice up. At that point I start working the throttle from full closed to
full open to try to break the ice off the carb slide. The ice sometimes
breaks off and the engine coughs a couple of times then continues to
run. Sometimes it gets bad enough that the carb slides are totally
stuck. At that point I choose a place to land, turn off the engine, and
do a dead stick landing.
Anyway the key for me is keeping an eye on the EGTs.
One more thing. After ice in the carbs melts, some of that water can run
down through the needle jets into the float bowls. That drop of water
can freeze into a pea sized ice pellet and block the main jet. Always
dump the float bowls after an icing event!
Q
Jan Nademlejnsky wrote:
| Quote: | I am very experienced "Rotax Flyer" with iced up carburetors. I fly (try to fly) in the winter, but the carburetor icing drives me crazy. When I was flying single cylinder Rotax 272 or Yamaha 286 it was easy. I carried on board hair dryer. As soon as I heard the engine coughing, I landed, removed carb, run to nearest car plugging, plugged in hair dryer *), melted ice, installed carb and flew again. This is not as easy now, with dual carb on my Rotax 582. The last time I flew, I did not feel or hear anything, but when I removed the air filter I saw the carb full of ice. It is scary and I do not know how the 582 would behave. Would it suddenly quit or is there any warning. I always wondered how people do it to fly in the winter with 2 stroke above hostile territory without fear the engine would quit.
*) I live in Canada, where everybody has outdoor car plug to keep car from freezing (-45C).
Jan Nademlejnsky
http://members.shaw.ca/jannadem/home.htm
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