182 O-470 burg burp on climbout

benyflyguy

benyflyguy

En-Route
Joined
Jan 1, 2018
Messages
3,755
Location
NEPA
Display Name
Display name:
benyflyguy
I was flying out to KYNG yesterday and back to pick up a friend. Flight out at 8000 she flew great. OAT was about 0 to 2C. Saw manifold pressure maybe drop a hair so I cycled carb heat for a few min

flight back climbing out full power passing through 7000’ engine takes a big burp- really shook the plane and us. Lasted only a second. Almost like you leaned too quickly. Real shudder. The fine. First thing I did was turn to the NRST on my gps. Then slowed my climb and pulled some heat on. No other issues. OAT was about 2C. Carb temp gauge was in the yellow. Which it was for most is the flight.
Plane is a 182H with an O-470 Continental. She does love to make ice. Seemed a bit more hazy on way back. No weather to speak of.
did I make a bit of ice?? I didn’t think I had to worry about ice on a full power climb out. I do advance throttle as I climb to keep MP up.
Pull a bit of water out of a tank?? Sumps clean before but water can hide.
 
I'd add some isopropyl fuel dryer to each tank. Not for carb ice, but to eliminate any water in the carb bowl.
 
Stewartb said:
I'd add some isopropyl fuel dryer to each tank. Not for carb ice, but to eliminate any water in the carb bowl.
Click to expand...
That’s good idea that’s easy enough to do. Have to fuel up so I can toss some in
 
Arbiter419 said:
Bet you a dollar she made some ice. Good odds if it's humid and you're behind a carbd continental. Above advice is also good.
Click to expand...
I’ve learned early that she’s an ice plant. My instructor for this plane was fanatic about it. I lock my throttle in cruise and monitor for any drop in MP- and drop will be a few min of carb heat flying. If conditions are ripe I’ll have heat on for large part of flight. This was my first with something full power in climbout.
in a few short years I’ve had plenty of suspected icing moments. Always fun when u pull the heat and she stumbles a bit more then u expected.
 
If you have a carb temp gauge, just use partial to keep it in the green. I usually aim to keep it 40-45 F.
 
benyflyguy said:
I’ve learned early that she’s an ice plant. My instructor for this plane was fanatic about it. I lock my throttle in cruise and monitor for any drop in MP- and drop will be a few min of carb heat flying. If conditions are ripe I’ll have heat on for large part of flight. This was my first with something full power in climbout.
in a few short years I’ve had plenty of suspected icing moments. Always fun when u pull the heat and she stumbles a bit more then u expected.
Click to expand...

I believe that! I've seen lots of O470 installs with a carb air temp gauge, are you lucky enough to have one by chance? Such great airplanes though.
 
Arbiter419 said:
I believe that! I've seen lots of O470 installs with a carb air temp gauge, are you lucky enough to have one by chance? Such great airplanes though.
Click to expand...
Yes it does. Nice to have as part of the scan.
 
Speaking from a meteorological standpoint the wx here in Ohio is pretty dry aloft so that would be interesting it found enough moisture to form ice.

Out of YNG towards the lake?
 
Todd82 said:
Speaking from a meteorological standpoint the wx here in Ohio is pretty dry aloft so that would be interesting it found enough moisture to form ice.

Out of YNG towards the lake?
Click to expand...
No heading back East yesterday late afternoon out of KYNG. Was a bit, a bit hazier at altitude then way out. CFI in in the plane with me shrugged it off as a bit of water got sucked in. Spooked me though. Was looking at options quick.
 
I had a 182 and I learned on my first flight you almost always seem to need a little carb heat. As stated before, watch that carb temp gauge, and know that you can dial in just enough to get out of the yellow. In a 172 I was taught all or nothing, in a 182 you just add what’s needed.
 
Doctor Bob said:
I had a 182 and I learned on my first flight you almost always seem to need a little carb heat. As stated before, watch that carb temp gauge, and know that you can dial in just enough to get out of the yellow. In a 172 I was taught all or nothing, in a 182 you just add what’s needed.
Click to expand...
That’s interesting. I was always taught that it was all or nothing. I thought that partial carb heat could lead to ice forming deeper in the carb where heat won’t be effective once it jams up so I never do that. I’ll have to read more about that.
 
Ours has never made much ice out here in the arid desert Southwest.

But...

I had a similar experience as you in the much more humid Midwest at a fairly high altitude. Saw lower power than expected, applied full carb heat, and the resulting blob of water going through the thing was nearly ... violent would be too big a term... but... interesting perhaps?

We don’t have the gauge. I’ve applied full heat in any visible moisture conditions and some others, ever since.

The big six banger doesn’t like swallowing a gob of water. Not at all. Especially up high where it’s not truly producing full power. It’s an “event” if you have to clear what I can only assume was a big ol’ gob of ice. Definitely enough of a power change that the prop governor chased it quite a bit.
 
What's happening with EGT? Our 172M (150 hp Lycoming) would first show carb ice as a reduction in EGT. By the time the manifold pressure was dropping it would really seriously iced up, although Lycs don't like to ice like Continentals.
 
@benyflyguy - you said you were full power but were you also leaned? I have had something similar happen when climbing out while also leaned. I still lean in the early climb but not so much. And once we start getting DA's even just above 2500 I even take off partially leaned as well. Carb heat doesn't just help eat ice it also makes the plane run a bit more rich. Maybe since you were up at 7000ft you were a bit too rich during that climb?
 
My 180 isn't prone to ice and I can't imagine any 0-470 making ice at full throttle. Low power is when they ice up. I've always had a carb temp gauge. Worthless.
 
Speaking of carb ice... This chart from the FAA Safety group's training on carb ice seems to me to have a glaring error. That or my understanding of Dew Point and Relative Humidity is completely wrong...

IcingChart.gif
 
smv said:
Speaking of carb ice... This chart from the FAA Safety group's training on carb ice seems to me to have a glaring error. That or my understanding of Dew Point and Relative Humidity is completely wrong...

View attachment 90209
Click to expand...

I believe what they’re not saying but including, is the effect a vacuum inside the Venturi has.

Essentially they’re giving outside the Venturi (ambient) numbers for inside the Venturi conditions.
 
benyflyguy said:
That’s interesting. I was always taught that it was all or nothing. I thought that partial carb heat could lead to ice forming deeper in the carb where heat won’t be effective once it jams up so I never do that. I’ll have to read more about that.
Click to expand...

I sometimes run partial heat in my 182 as does a lot of other skylane drivers. It helps balance the fuel/ air mixture between the cylinders so you can run leaner

If you fly a skylane this is a must read:
https://www.cessnaflyer.org/media/k...ane_Pilots_Companion-A_Pilot's_Guide-book.pdf
 
benyflyguy said:
That’s interesting. I was always taught that it was all or nothing. I thought that partial carb heat could lead to ice forming deeper in the carb where heat won’t be effective once it jams up so I never do that. I’ll have to read more about that.
Click to expand...

I was taught the same on a 172. My very first flight in my new to me 182 with an instructor experienced carb ice within minutes of flying with no carb heat. Soon I got a letter in the mail from Cessna warning of potential carb ice and to use partial carb heat whenever needed. My mechanic explained how the carbs are further away from the block on an 0-470 which exaggerates the icing dilemma. Interestingly, my Flight Design I fly now has the carbs arranged so they basically will never ice. I don’t even know if they have carb heat on the European models but have it installed in all USA imports. My check lists say to always make sure the carb heat is off.
 
Stewartb said:
My 180 isn't prone to ice and I can't imagine any 0-470 making ice at full throttle. Low power is when they ice up. I've always had a carb temp gauge. Worthless.
Click to expand...

mine did, 10.5K over the Cascades in WA. O-470R, 182J (66).
 
Stewartb said:
My 180 isn't prone to ice and I can't imagine any 0-470 making ice at full throttle. Low power is when they ice up. I've always had a carb temp gauge. Worthless.
Click to expand...

I had the club's C182P make ice in some clouds during a flight. Carb heat caused a bit of stumbling and then smooth running once the water got out of the system. The only clue I had prior to adding heat was the need to keep increasing the throttle to maintain power. So, yes, they can make ice.
 
Any carb can make ice. The mystery with Cessnas is why two seemingly identical airplanes make ice differently, and they do. Mine's made ice in a low power descent as I picked my way around clouds until I got under a 600' ceiling. Very predictable. In a full power climb on that same day? I wouldn't expect ice.
 
Or a relevant comment from some people. My comment is from experience in this plane.
 
I've got about 120 hours on my 182 (PPONK) since I bought it at the end of Feb. I live in Michigan, so I've flow in a lot of different weather from Feb till now. I have yet to get any carb ice (that I know of anyway). I was taught to add carb heat when in the clouds and whenever I'm pulling power for a decent. I have a JPI 900 with carb temperature probe and if I see the tem get below freezing I'll add some carb heat and watch the tem go up. To be honest I'm a bit nervous about carb icing. The more I read about preventive measures the more I wonder if I'm doing the right thing. I have noticed when at cruse if I add carb heat my fuel burn goes up dramatically. If I'm at 22 / 2300 no carb heat, I'm burning about 14gph, if I add carb heat it jumps to 18gph. Should I be leaning it back down to 14? I understand the hot air is less dense and I don't need as much fuel to maintain the same mixture. But I don't understand why my GPH would change if I don't touch the mixture. I can see my MPG changing but I don't understand the GPH changing.
 
Just adding hot (less dense) air in the carb enriches the mixture. Red knob not involved.
 
bobmrg said:
Just adding hot (less dense) air in the carb enriches the mixture. Red knob not involved.
Click to expand...

I understand that it enriches the mixture because you have less air but I don't understand why my GPH number goes up. I didn't move the red knob so why does my GPH change? I'm sure its something I just don't understand.
 
probably swallowed a wasp nest or something, forgettabotit.


A 172 at my home field a while ago ended up in a cornfield that way.
 
denverpilot said:
I believe what they’re not saying but including, is the effect a vacuum inside the Venturi has.

Essentially they’re giving outside the Venturi (ambient) numbers for inside the Venturi conditions.
Click to expand...

Just seems confusing to demonstrate 100% humidity is when the Dew Point is 10° above the temperature. Of the several Carb Ice charts I have seen, the one from FAA Safety is the only one that does this.
 
AlphaMike said:
I've got about 120 hours on my 182 (PPONK) since I bought it at the end of Feb. I live in Michigan, so I've flow in a lot of different weather from Feb till now. I have yet to get any carb ice (that I know of anyway). I was taught to add carb heat when in the clouds and whenever I'm pulling power for a decent. I have a JPI 900 with carb temperature probe and if I see the tem get below freezing I'll add some carb heat and watch the tem go up. To be honest I'm a bit nervous about carb icing. The more I read about preventive measures the more I wonder if I'm doing the right thing. I have noticed when at cruse if I add carb heat my fuel burn goes up dramatically. If I'm at 22 / 2300 no carb heat, I'm burning about 14gph, if I add carb heat it jumps to 18gph. Should I be leaning it back down to 14? I understand the hot air is less dense and I don't need as much fuel to maintain the same mixture. But I don't understand why my GPH would change if I don't touch the mixture. I can see my MPG changing but I don't understand the GPH changing.
Click to expand...
You question is a bit of an aside to the post however it has me intrigued as well.

In our 182P when we pull carb heat, in the summer in the pattern it is crazy rich. You can pull the mixture out signficantly...like almost half way out (to demonstrate only). Thats just one easy example of how rich it runs.

In your case you have a independent measure of fuel flow so there is no doubt it is drawing more. First question is if yours is fuel injected - I don't think so. So then maybe it goes like this. You are cruising along 22"/2300rpm. The fuel is being gravity fed down to the lowest part of the plane and has a slight head of pressure on it. The vacuum of the engine is pulling in the fuel+air mixture in a certain ratio (I probably have that wrong). Then you only pull out carb heat. There is no linkage directly connected to the throttle or mixture setting. The hot air over the exhaust now starts flowing in along with some fresh outside air. I would think that hotter air can carry more fuel now (maybe I got that wrong too LOL)? So since there is ample fuel available and the air can take more fuel it "draws" in more than before the carb heat was pulled out. And thus the independent indication of higher GPH. Just a theory anyways.
 
Stewartb said:
My 180 isn't prone to ice and I can't imagine any 0-470 making ice at full throttle. Low power is when they ice up. I've always had a carb temp gauge. Worthless.
Click to expand...
Definitely agree on that damn [optional] gauge being worthless. About the only time the needle isn't in the warning zone is when its -10F.

We have made ice twice, once at full power and once at almost full throttle. The first time was a crazy humid morning and scattered layer. We were breaking in the top end so flying it full power. Never did enter a cloud or even a wisp of a cloud though. The wife was flying and I hadn't learned yet. I still remember that "weird 2 or 3 seconds" where she noticed something wasn't right, resisted the urge to reach for more power, checked the MP and pulled carb heat. Cured it right up.

Just like another poster, happened to me during training. We had just departed the field and right as we leveled off still full power and mixture rich it started making ice. It wasn't bad so we kept flying and he made it into a great learning session. We used carb heat frequently but didn't need it continuously.

So I think we've made ice twice at or near full throttle, full rich. But both times was visible moisture.

I don't think OP was making ice on the climb out. Unless there was lots of moisture in the air like clouds or rain or freezing rain. Now maybe he was partially iced down on the ground and it caused this during the climb?
 
Last edited:
Omalley1537 said:
mine did, 10.5K over the Cascades in WA. O-470R, 182J (66).
Click to expand...
My O-200 got ice for the first time after I did a winter climb from 600' to 13,500' full power the whole time and clear dry air. But full power at 13,000' in an o-200 is far from the 100Hp rated power.
 
Sinistar said:
You question is a bit of an aside to the post however it has me intrigued as well.

In our 182P when we pull carb heat, in the summer in the pattern it is crazy rich. You can pull the mixture out signficantly...like almost half way out (to demonstrate only). Thats just one easy example of how rich it runs.

In your case you have a independent measure of fuel flow so there is no doubt it is drawing more. First question is if yours is fuel injected - I don't think so. So then maybe it goes like this. You are cruising along 22"/2300rpm. The fuel is being gravity fed down to the lowest part of the plane and has a slight head of pressure on it. The vacuum of the engine is pulling in the fuel+air mixture in a certain ratio (I probably have that wrong). Then you only pull out carb heat. There is no linkage directly connected to the throttle or mixture setting. The hot air over the exhaust now starts flowing in along with some fresh outside air. I would think that hotter air can carry more fuel now (maybe I got that wrong too LOL)? So since there is ample fuel available and the air can take more fuel it "draws" in more than before the carb heat was pulled out. And thus the independent indication of higher GPH. Just a theory anyways.
Click to expand...

I'm curious as well, as it was my understanding that using carb heat enriched the mixture simply because the hot air is less dense (i.e. less air mass with the same fuel flow making the mixture more rich). I'm interested in the mechanism for the increased fuel flow in this scenario.
 
I’ve got a 182H as well, had about a year and a half. While mine hasn’t seemed to make much ice in the conditions I’ve flown in so far, I think I might have been lucky. I don’t have a working carb ice indicator. this thread is a good reminder for me as I just got my instrument ticket a few weeks ago and will be flying in more moisture this fall/winter.
 
You must log in or register to reply here.
Back
Top