c152 engine quit immediately after landing
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To answer Bose's point, yes my Gipsy would do the same.
Once the temp was below 0C it would take 20 plus minutes to warm up sufficiently to take off and by the time I landed and taxied back to the hangar it needed to be rev'd a little to keep it going.
Running in warm air did not seem to help that much to keep it going but it was noticeable that the oil temperature would only just be within the operating zone by the time I got to the hangar. The engine would be just warm to the touch by this time. Starting was always a little interesting - you had to catch it with the throttle before it used the rich mixture in the manifold - and as the starter was barely man enough to turn it over that usually meant hand swinging.
Given the Gipsy's less than sophisicated induction arrangements it may be more about the mixture at tickover than drag - either way it certainly used to happen to mine!
Once the temp was below 0C it would take 20 plus minutes to warm up sufficiently to take off and by the time I landed and taxied back to the hangar it needed to be rev'd a little to keep it going.
Running in warm air did not seem to help that much to keep it going but it was noticeable that the oil temperature would only just be within the operating zone by the time I got to the hangar. The engine would be just warm to the touch by this time. Starting was always a little interesting - you had to catch it with the throttle before it used the rich mixture in the manifold - and as the starter was barely man enough to turn it over that usually meant hand swinging.
Given the Gipsy's less than sophisicated induction arrangements it may be more about the mixture at tickover than drag - either way it certainly used to happen to mine!
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The engine quited on the ground when adding power for a touch and go. Restarted it, re-checked for normal operation and flew back home. I decided to give it another try at the 1800m asphalt rwy and the engine died AGAIN. This time I was particularly vigilant about the fact of increasing the throtle in a VEEEEEEERY smooth and slow fashion and left carb heat almost all the way to touch down.
Ppl at school blamed the problem on me saying I probably added power too quickly.
Ppl at school blamed the problem on me saying I probably added power too quickly.
A Piper cub I used to fly simply did not have an accelerator pump at all. The use of the throttle had to be very gentle at all times, particularly in flight. If you jammed the throttle, and it quit, you'd have to get out and hand prop it (no starter). This could not be practically done in flight, so you were now doing a forced approach.
Always fly carburetted planes with gentle throttle movements, as though you had a failed accelerator pump, and you'll have much more assured engine response.
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I've had the exact same thing happend to me. Pattern altitude for the airport was 1500ft so a rather "long" descent was necesary. I remember using flaps to increase my descent angle / required power and setting the carb heat to the cold position about 100ft above the threshold. The engine quited on the ground when adding power for a touch and go. Restarted it, re-checked for normal operation and flew back home. I decided to give it another try at the 1800m asphalt rwy and the engine died AGAIN. This time I was particularly vigilant about the fact of increasing the throtle in a VEEEEEEERY smooth and slow fashion and left carb heat almost all the way to touch down.
Ppl at school blamed the problem on me saying I probably added power too quickly.
Ppl at school blamed the problem on me saying I probably added power too quickly.
Anyways...
My question for you is why did you put the carb heat to the cold position 100' still in the air?! You should not be doing that. You should have carb heat hot until AFTER you've added full power.
1) Pull carb heat before reducing power as you start your descent in to land
2) Touch down with carb heat hot
3) Add full power
4) Push carb heat cold
5) Enjoy your flights!
Always advance the throttle slowly, even with carb heat on and even with an accelerator pump.
I kinda doubt you had carb ice. I've been flying 152's with the 235 engines for quite a while now and operated them in -25 Celsius weather. I've only ever gotten carb ice on the ground after start when the engine was cold (and the day was quite humid... all the days that I predicted I would get carb ice based on walking out to my car and feeling/seeing the humidity... I did get it on the ground). Once the engine had warmed up a bit, I did the runup and never experienced ice for the rest of the flight. I'd pull carb heat hot and power idle to get the lowest RPM after the runup to confirm the engine still runs. It would stay around 500-600 RPM and then I put carb heat cold... the engine still ran, no carb ice. Then put the power to 1000 RPM for idle.
On power-off descents even with carb heat hot, the engine should be runup to the green arc ~ every 500 ft of descent. When it's really cold and I'm teaching a student to do a forced landing, I'll put in 30 flaps and set it up with the glide speed and proper descent rate by using the power. Then when they want to simulate adding flaps on the final approach they just pull the power back, and at idle it would obviously be 30 flaps.
Someone also mentioned that cruising back with carb heat hot was a bad idea.... because of the unfiltered air. At the cold temps he was operating at the cold temps would have created probably the cleanest air you could possibly hope for! As long as he wasn't flying through a dust storm, he was fine. Second problem I have with that is the instructor putting on FULL carb heat. IMO, and the opinion of the C152 POH published by Cessna himself, you should only operate with the necessary carb heat on. He should have experimented to see if carb heat was necessary, and if it was, which I highly doubt in his situation, he should have used partial carb heat. PS: full carb heat causes an excessively rich mixture which sometimes can't be compensated for even by leaning the mixture with the recommended lean mixture procedure listed in the POH.
And that brings me to another point. I will bet $1000 that you will not be able to get a O-235 engine to get carb ice when you have full carb heat on while flying through high humidity air at the optimum carb ice temp, excluding cloud, and remaining in VMC. There is sufficient heat to be able to melt the ice while at cruise RPM and at full carb heat. Now, if you do happen to pick up ice while at cruise RPM with carb heat cold (again, quite unlikely... however I won't knock the possibility of it), then you should fly only with partial carb heat on. The instructor should have been more aware of the consequences of running with carb heat hot (however, not dangerous) and been aware of the proper operating procedures.... as well as the mostly likely problem was adding throttle too fast which caused an excessively rich mixture and the engine cut.
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italia, I cannot agree with:
as I know there is a tremendous amount of wisdom among the group here. Yes, any forum, can have postings by incompletely infomred well meaners, but it is up to the reader to decide for him/her self what information is credible, by considering it in the context of all other knowledge available.
Having read your warning, I'm not quite sure how to take the page of text which follows the warning.... A little of it I find to be weird and scary....
In particular, the use of partial carb heat, with out a carb air temperature indicator, is a poor idea. Water which might go right through the carb frozen, and harmless, could be melted, and refreeze because of the use of partial carb heat. Great caution must be used doing this.
If you're flying in -25C weather, I doubt that carb ice is a risk at all, and in those conditions (which I fly from time to time) I do not bother with carb heat at all, but that is my personal preference, not instruction.
Cruising with carb heat hot would not be commonly necessary. If it is necessary, proper leaning is important, as the hot induction air will richen the mixture, and correction of this is appropriate.
I'm not sure how you would be certain who, posting here, is a PPL, rather than other licenses. But I can assure you with absolute certainaty, that the type of pilot's license, is not a direct indicator of knowledge or experience here. Some PPL's really have a lot to offer....
There is a lot of really weird and scary stuff that ppl are saying on here. My advice to you is don't listen to everything ppl tell you on a forum site! You're better off doing some of your own research yourselves instead of being lazy and going to a forum.
Having read your warning, I'm not quite sure how to take the page of text which follows the warning.... A little of it I find to be weird and scary....
In particular, the use of partial carb heat, with out a carb air temperature indicator, is a poor idea. Water which might go right through the carb frozen, and harmless, could be melted, and refreeze because of the use of partial carb heat. Great caution must be used doing this.
If you're flying in -25C weather, I doubt that carb ice is a risk at all, and in those conditions (which I fly from time to time) I do not bother with carb heat at all, but that is my personal preference, not instruction.
Cruising with carb heat hot would not be commonly necessary. If it is necessary, proper leaning is important, as the hot induction air will richen the mixture, and correction of this is appropriate.
I'm not sure how you would be certain who, posting here, is a PPL, rather than other licenses. But I can assure you with absolute certainaty, that the type of pilot's license, is not a direct indicator of knowledge or experience here. Some PPL's really have a lot to offer....
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One thing to bear in mind.
The OP was flying a 152, others have mentioned 150s.
Whilst the 152 is not carb ice proof, I've always found the 150 a little more prone, due to the way the Continental engine is configured, compared to the Lycoming in the 152.
Just worth considering in the back ground.
The OP was flying a 152, others have mentioned 150s.
Whilst the 152 is not carb ice proof, I've always found the 150 a little more prone, due to the way the Continental engine is configured, compared to the Lycoming in the 152.
Just worth considering in the back ground.
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In particular, the use of partial carb heat, with out a carb air temperature indicator, is a poor idea. Water which might go right through the carb frozen, and harmless, could be melted, and refreeze because of the use of partial carb heat. Great caution must be used doing this.
If you're flying in -25C weather, I doubt that carb ice is a risk at all, and in those conditions (which I fly from time to time) I do not bother with carb heat at all, but that is my personal preference, not instruction.
If you're flying in -25C weather, I doubt that carb ice is a risk at all, and in those conditions (which I fly from time to time) I do not bother with carb heat at all, but that is my personal preference, not instruction.
The times that I have gotten carb ice has been at very cold temps where the humidity was high.
I do agree that there are some bright PPL students with either knowledge or experience that is quite good. However, I see way too many times ppl making suggestions or instructing ppl to do something that is quite dangerous. I'm quite surprised that after over 1 page of posts, no one that I saw mentioned reading the POH! (One mentioned reading a flight manual.... "Aside from a possible reference in the flight manual, there is no way for you as the pilot to know if the carb is [equipped with an accelerator pump] other than how it behaves."... however, that is completely false!) There is a section in the C152 POH regarding cold weather ops. I do use the forums for some helpful insight and guidance but as an instructor I can hardly tell my superior or students that the information I'm providing them with is correct because I found it from a reputable forum site. If you want hard data and answers, talk to Lycoming, talk to Cessna, read the documents that they published on the engine and aircraft.
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One thing to bear in mind.
The OP was flying a 152, others have mentioned 150s.
Whilst the 152 is not carb ice proof, I've always found the 150 a little more prone, due to the way the Continental engine is configured, compared to the Lycoming in the 152.
Just worth considering in the back ground.
The OP was flying a 152, others have mentioned 150s.
Whilst the 152 is not carb ice proof, I've always found the 150 a little more prone, due to the way the Continental engine is configured, compared to the Lycoming in the 152.
Just worth considering in the back ground.
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there is no way for you as the pilot to know if the carb is [equipped with an accelerator pump] other than how it behaves."... however, that is completely false!)
Though it is mentioned in some flight manuals, it is certainly not required to be. It could be a feature, or not, with no mention either way. Access to the parts catalog, or overhaul manual for the carb would tell a person with certainty, but I presume that generally pilots do not have access to these documents.
The accelerator pump is not closely linked with cold weather operation, though is a factor. If an engine design incorporates an accelerator pump, it would be because it needed it. Accelerator pumps are a "weak link" in carbs, in that they do break down over time, and out right fail. If the engine needed it, and it was not fuctioning, the engone would do as the poster described.
As for the relationship between a "POH" and a "Flight Manual", in nearly all cases, the POH is the approved flight manual. There are a few aircraft types (Twin Comanche being one) where the POH, and Flight Manual are separate documents. In this case, the Flight Manual is to prevail, as it is required by regulation, and the POH will tell yout that. It would be very unlikely that a POH and Flight Manual presented conflicting information, though I have experience with POH's which are not correct.
For my benefit (because I do not have a C 152 Flight Manual at my disposal) may I ask you to describe the conditions in which Cessna recommends the use of partial carb heat? This would be very surprising for me! Without a carb air temperature indicator (very uncommon in 152's) it would be nearly impossible for a pilot of any amount of skill, to know the effect of the application of "some" carb heat, or how much to apply. As the risk of a problem from the use of partial carb heat far exceedes the diadvantage of full carb heat, I would be surprised to see it recommended at all, and never have.
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So you're suggesting that there is a certain way for the pilot to know if the carb of a given aircraft is equipped with an accelerator pump with certainty?
Though it is mentioned in some flight manuals, it is certainly not required to be. It could be a feature, or not, with no mention either way. Access to the parts catalog, or overhaul manual for the carb would tell a person with certainty, but I presume that generally pilots do not have access to these documents.
Though it is mentioned in some flight manuals, it is certainly not required to be. It could be a feature, or not, with no mention either way. Access to the parts catalog, or overhaul manual for the carb would tell a person with certainty, but I presume that generally pilots do not have access to these documents.
The accelerator pump is not closely linked with cold weather operation, though is a factor. If an engine design incorporates an accelerator pump, it would be because it needed it. Accelerator pumps are a "weak link" in carbs, in that they do break down over time, and out right fail. If the engine needed it, and it was not fuctioning, the engone would do as the poster described.
Btw.. your justification for having an accelerator pump based on if it "needed" it is a little off IMO. Need is one of the most ambiguous words in the english language.
As for the relationship between a "POH" and a "Flight Manual", in nearly all cases, the POH is the approved flight manual. There are a few aircraft types (Twin Comanche being one) where the POH, and Flight Manual are separate documents. In this case, the Flight Manual is to prevail, as it is required by regulation, and the POH will tell yout that. It would be very unlikely that a POH and Flight Manual presented conflicting information, though I have experience with POH's which are not correct.
For my benefit (because I do not have a C 152 Flight Manual at my disposal) may I ask you to describe the conditions in which Cessna recommends the use of partial carb heat? This would be very surprising for me! Without a carb air temperature indicator (very uncommon in 152's) it would be nearly impossible for a pilot of any amount of skill, to know the effect of the application of "some" carb heat, or how much to apply. As the risk of a problem from the use of partial carb heat far exceedes the diadvantage of full carb heat, I would be surprised to see it recommended at all, and never have.
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My assumption has been that if its a carburated Lycoming or Continental then it probably has an Marvel with accelerator pump unless it instead has a Stromberg carb, as fitted to the smallest, earliest engines like the A65 I own.... All smaller than an O-235. Accurate or no?
For sure I've found that a Stromberg equipped engine can quit on a cold day if you advance the throttle quite rapidly from low rpm. Particularly true if the engine is cold as well as the air.
For sure I've found that a Stromberg equipped engine can quit on a cold day if you advance the throttle quite rapidly from low rpm. Particularly true if the engine is cold as well as the air.
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Pilot DAR:
I found an online copy of the C152 POH and it says this in the emergency section:
"If conditions require the continued use of carburetor heat in cruise flight, use the minimum amount of heat necessary to prevent ice from forming and lean the mixture slightly for smoothest engine operation."
An important note about that, it also says:
"When operating in temperatures below -18°C, avoid using partial carburetor heat. Partial heat may increase the carburetor air temperature to the 0°C to 21°C range, where icing is critical under certain atmospheric conditions."
Like you said tho, I'd rather someone used full carb heat in doubt and not mess around with partial carb heat. The situations where you'd use partial carb heat happen hardly ever and you really shouldn't get yourself in that situation ever in a 152. Another indication that partial carb heat is not to be a "normal procedure" in the 152 is that it's actually in the emergency section of the POH.
I found an online copy of the C152 POH and it says this in the emergency section:
"If conditions require the continued use of carburetor heat in cruise flight, use the minimum amount of heat necessary to prevent ice from forming and lean the mixture slightly for smoothest engine operation."
An important note about that, it also says:
"When operating in temperatures below -18°C, avoid using partial carburetor heat. Partial heat may increase the carburetor air temperature to the 0°C to 21°C range, where icing is critical under certain atmospheric conditions."
Like you said tho, I'd rather someone used full carb heat in doubt and not mess around with partial carb heat. The situations where you'd use partial carb heat happen hardly ever and you really shouldn't get yourself in that situation ever in a 152. Another indication that partial carb heat is not to be a "normal procedure" in the 152 is that it's actually in the emergency section of the POH.
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your justification for having an accelerator pump based on if it "needed" it is a little off IMO
An example of this might be a client's modified aircraft, stored here at my home aerodrome now, which has not shown compliance with the requirements for heat rise with the applicaton of carb heat, during flight testing I have done. That said, in my 58 hours of flying this aircraft, I have never had a carb heat/ice problem become apparent with it. But, to comply, it will "need" a design change - no approval otherwise...
My Cessna 150 has been equipeed with a carb air temp guage for the 24 years I have owned it. Aside from checking the operation of the carb heat preflight, I never apply carb heat, at any point in the flight, unless the carb air temperature is within the caution temperature range. (one exeception - I did on my CPL flight test last summer, 'cause it was easier to do it, than explain why I would not). I run nothing but Mogas, and have never had a problem with carb ice in flight. I have used the carb heat control for it's alternate air function twice in emergencies in flight. Those emergencies were not associated with carb ice at all.
Though I accept that apparently Cessna did make a reference to the use of partial carb heat under some circumstances in the 152 flight manual, I think this is an oddity, and was not repeated (I've never seen it anywhere else, and I read a lot of flight manuals). But, I agree, I have not read a C 152 flight manual since I did my first solo, in the first one into Canada, in 1977 - Wait, I don't even think I read that one! I just flew it like a brand new 150, but wondered where the rest of the flaps were!
Marvel with accelerator pump
Yes, a quick call or dropping by your AME's shop will confirm with certainty, assuming your AME is qualified, properly completes his job and doesn't lie, that you do or do not have an accelerator pump.
I really do trust that aircraft maintainers do not lie. It's part of the faith I have, in the compotence and ethics of my fellow professionals in this industry. I don't lie, I trust others don't either... Some just are not as familiar with details as they might be.
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Pilot DAR:
I would actually like to get some experience with a carb air temp gauge and see what it indicates in different atmospheric conditions. In a way it's kind of blind faith the way the majority of ppl fly with a carb engine and I would think that a simple, probably relatively cheap probe could eliminate the curiosity as well as prevent a few crashes. Seems a no brainer to have them as standard equipment.
I think you'd be surprised at the amount of info the average pilot doesn't know about his aircraft, without being able to reference his POH or flight manual. There is quite a bit to know and understandably you can't expect them to know everything by memory. Being an instructor has been good for me I think because I really don't like being asked a question about an aircraft I fly and INSTRUCT on and have to tell them I don't know the answer! That motivates me to learn, and in the aviation world, you never really stop learning. The more information and insight I can pass on to my students I think the better. I find most of my students are really interested in understanding the concepts, especially the mature adults. A few of them sometimes just want to have a discussion about different things which I think is great.
Regarding AMEs lying... I was joking there! I believe they are honest people. The maintenance staff that I work with are fantastic and love to chat about the airplanes. They have helped clear up some aircraft related questions I've had in the past.
I would actually like to get some experience with a carb air temp gauge and see what it indicates in different atmospheric conditions. In a way it's kind of blind faith the way the majority of ppl fly with a carb engine and I would think that a simple, probably relatively cheap probe could eliminate the curiosity as well as prevent a few crashes. Seems a no brainer to have them as standard equipment.
I think you'd be surprised at the amount of info the average pilot doesn't know about his aircraft, without being able to reference his POH or flight manual. There is quite a bit to know and understandably you can't expect them to know everything by memory. Being an instructor has been good for me I think because I really don't like being asked a question about an aircraft I fly and INSTRUCT on and have to tell them I don't know the answer! That motivates me to learn, and in the aviation world, you never really stop learning. The more information and insight I can pass on to my students I think the better. I find most of my students are really interested in understanding the concepts, especially the mature adults. A few of them sometimes just want to have a discussion about different things which I think is great.
Regarding AMEs lying... I was joking there! I believe they are honest people. The maintenance staff that I work with are fantastic and love to chat about the airplanes. They have helped clear up some aircraft related questions I've had in the past.
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Flying all the way with the carb heat on is pretty dangerous, probably more so than your initial problem. You also risk damaging the engine as the air entering the engine is unfiltered with the carb heat on.
If you do then experience carb icing (which is still possible to get with the carb heat on), you have left yourself no way of getting rid of it and then your will find yourself in a real emergency situation.
If you do then experience carb icing (which is still possible to get with the carb heat on), you have left yourself no way of getting rid of it and then your will find yourself in a real emergency situation.
It's not dangerous, pretty or otherwise. Your'e not going to damage the engine, either.
If you're using carburetor heat, the notion that "if you then experience carburetor icing..." is irrelevant, as is the subject of removing the carburetor ice. Your statement suggests a lack of understanding of the function of carburetor heat.
Carburetor heat is used to take the carburetor airflow out of the icing band, or icing range. It's either in an icing range, or it's not.
Having carburetor heat on does not mean that you've used up your ace card and have no more resources, if carb ice forms; if carb ice begins to form, then your carburetor heat had put the airflow through the carburetor within the icing range. Shut it off. The problem with your logic is that because most light airplanes aren't equipped with carburetor air temperature gauges, carb heat tends to work hotter than necessary; if carb heat is applied, you shouldn't be building ice, period.
The situations where you'd use partial carb heat happen hardly ever and you really shouldn't get yourself in that situation ever in a 152.
Nothing more.
My assumption has been that if its a carburated Lycoming or Continental then it probably has an Marvel with accelerator pump unless it instead has a Stromberg carb, as fitted to the smallest, earliest engines like the A65 I own.... All smaller than an O-235. Accurate or no?
My question for you is why did you put the carb heat to the cold position 100' still in the air?! You should not be doing that. You should have carb heat hot until AFTER you've added full power.
1) Pull carb heat before reducing power as you start your descent in to land
2) Touch down with carb heat hot
3) Add full power
4) Push carb heat cold
5) Enjoy your flights!
1) Pull carb heat before reducing power as you start your descent in to land
2) Touch down with carb heat hot
3) Add full power
4) Push carb heat cold
5) Enjoy your flights!
At the cold temps he was operating at the cold temps would have created probably the cleanest air you could possibly hope for!
I've done atmospheric research flying in which I took samples of atmosphere at various altitudes and temperatures, and have encountered considerable particulates in some very cold temperatures. Temperature has no bearing on air contamination.
Now, if you do happen to pick up ice while at cruise RPM with carb heat cold (again, quite unlikely... however I won't knock the possibility of it), then you should fly only with partial carb heat on.
Carburetor ice in cruise can certainly happen, and when one gets carburetor icing, one should use full carburetor heat unless one has a carburetor air temperature gauge. Once the ice is gone, one may continue using partial heat by trial and error. One should avoid full carburetor heat if operating at high power settings, but this normally isn't a problem in a normally aspirated airplane. It can be a problem in a turbocharged or supercharged engine installation. The issue there is the temperature of the induction air, and the potential for detonation.
The instructor should have been more aware of the consequences of running with carb heat hot (however, not dangerous) and been aware of the proper operating procedures.... as well as the mostly likely problem was adding throttle too fast which caused an excessively rich mixture and the engine cut.
This is untrue.
In fact, the reason for using an acceleration pump is to enrichen the mixture during engine acceleration, specifically when opening the throttle. Opening the mixture quickly doesn't cause a "rich out," but rather makes the mixture too lean. The purpose of an acceleration pump is to add additional fuel to enable smooth acceleration when opening the throttle. If the throttle is opened too quickly, the engine won't get enough fuel fast enough, and may stumble and in some cases can even die.
What is not happening is a "rich out."
In the case of the airplane being operated by the original poster, given the air temperature, the air density is greater than normal. Almost certainly greater than the last time the idle mixture was adjusted.
Most pilots are unaware that their carburetor has two mixture settings; one they can control, and one they cannot. The cockpit mixture control doesn't adjust idle mixture, or the mixture of the idle jet; that's done by the idle mixture setting, and is adjusted with a screw setting on the carburetor body itself. It's adjusted by a mechanic, and should be readjusted any time the aircraft is operated in different climatic conditions or a different density altitude than that at which it was originally set. Idle mixture may need readjustment seasonally, or if the aircraft has been moved to a different base at a different elevation. Idle mixture is the mixture setting at which the engine will run with the throttle closed and no effort by the pilot to starve the engine of fuel.
When sitting at idle on the ground, use of the mixture control has no effect on leaning the engine, until one has nearly cut off the fuel entirely. This isn't really leaning, in the sense that one is adjusting the mixture, but a very rough process of simply partially cutting off fuel. A little like the difference between finely adjusting a valve, and putting your finger in front of the end of a garden hose.
If Idle mixture has been set in the winter time in dense air, it will be overly rich in the summer, and one may experience leading of spark plugs, rough engine, and other problems, especially at idle settings. Conversely, if idle mixture has been adjusted in the summer time, it may be too lean, and the engine may have a tendency to die in the winter time, at idle power settings.
If your engine was running smoothly with the carburetor air applied, you had artificially enrichened the mixture by using the carburetor heat. By increasing the induction air temperature, you lowered air density, which meant a richer mixture. When shutting off the carburetor heat, you increased the air density of the induction airflow, meaning a leaner mixture. If the idle mixture was already very lean because of having been set in the summer on a hot day, then you could very well cause the engine to hesitate or fail by advancing the throttle. In this case, it is NOT a "rich out." It's simply died for lack of fuel.
Idle mixture is easy to check, and should be done before every engine shut down as part of the post flight procedures. Each aircraft engine manufacturer recommends it, though it's not often found in the aircraft flight manual.
Do a runup on the ground, slowly leaning the engine until it nearly dies. Run it this way for a few moments, then enrichen the mixture and pull the throttle to idle. Let it idle for a few moments. Now, watching the RPM gauge, slowly retard the mixture to cutoff. Just prior to cutoff, you'll see an RPM rise. The RPM should rise a maximum of 25 rpm or so. If it's a rise of 50 RPM or higher, you have too rich an idle mixture setting, and it needs to be adjusted by a mechanic. If you have no rise at all, then your idle mixture is too lean.
Chances are that the original poster's airplane had it's idle mixture last adjusted in the summer time, and is too lean, especially for the cold winter conditions. Pushing in the mixture control in the cockpit will have no effect on enrichening the idle mixture. If the idle mixture is too lean, advancing the throttle, especially if advanced too quickly, can kill the engine. This only occurs, however when advancing the throttle off the idle position. If at a partial power position, the carburetor idle jet is inactive and idle mixture is irrelevant. So, if the original poster landed with idle throttle, shut off the carburetor heat (thus further leaning the engine), and then advanced the throttle from a closed position, there's a very good chance he engine would cough or die...which did, in fact, happen.
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The maintenance staff that I work with are fantastic and love to chat about the airplanes
Carb air gauges are easly installed, if the aircraft owner is so inclined. It' a matter of percieved value, as it the case with most elective things we do to aircraft!
