In a climb attitude, my '65 Champion Citabria with the 0-200 engine always seems to run too rich. If I lean it out correctly, I gain something like 150-200 RPM. Once we are back in cruise attitude, the problem disappears and the engine wants to run with a richer mixture. Various tinkering and replacement of the carburetor seem to have had no effect. I have spoken with four AME's and none seems to have any positive ideas. Thoughts?
Carburation
- Thread starter Alex
- Start date
wjwilson2000
New member
Have you applied carb heat once your at a safe altitude? Your not getting carb heat all the time are you? The reason I mention this is I had a friend that ran into carb ice on a regular bases with a Cessna 150 with the O-200. They will literaly ice during cruise flight and not really on a day when you would think of carb ice. Just a thought!!!!
Woodie
N29763
Woodie
N29763
Alex,
Are you wide open in climb and then bringing the throttle back in cruise? Throttle plate position has a lot to do with division of airflow. Some intakes are much worse than others, many times a small movement in throttle plate position will make a huge difference in all 4 cylinders getting a close to even air flow, thus a even fuel mixture as well.
Are you wide open in climb and then bringing the throttle back in cruise? Throttle plate position has a lot to do with division of airflow. Some intakes are much worse than others, many times a small movement in throttle plate position will make a huge difference in all 4 cylinders getting a close to even air flow, thus a even fuel mixture as well.
Mr. Scout.
Thanks for the thought. I will speak with my AME about that. I am finding that in climb if I either bring the throttle back to what would be about 75% or if I lean the engine I get the same result: an increase in power. The same seems to be true in level flight. In level flight if I advance the throttle to the stop, I also lose power beyond what would be about 75%. It's as if, when I advance the throttle beyond a certain point, I actually lose power both in climb and in cruise attitude. Carburetor ice is not causing this problem, although, as Woodie pointed out, the 0-200 is an ice magnet even in good conditions.
Thanks for the thought. I will speak with my AME about that. I am finding that in climb if I either bring the throttle back to what would be about 75% or if I lean the engine I get the same result: an increase in power. The same seems to be true in level flight. In level flight if I advance the throttle to the stop, I also lose power beyond what would be about 75%. It's as if, when I advance the throttle beyond a certain point, I actually lose power both in climb and in cruise attitude. Carburetor ice is not causing this problem, although, as Woodie pointed out, the 0-200 is an ice magnet even in good conditions.
Scaramonga
New member
I would suggest having your mechanic take a close look at your carb heat box. Sounds to me as if your carb heat is always partially on. I recently had my carb heat box rebuilt because the carb heat box door was a smidgen out of position, causing a rich mixture.
Robert Szego
New member
Remove muffler(s) and check for loose baffling. When they separate internally, they tend to slide backwards when nose high and block the exhaust, giving the old "potato in the tailpipe" effect.
Regards,
Regards,
Thanks to the people who replied to my note. We hired a new AME for our school and he went straight to the problem: the carb heat box was old, tired, worn and leaking hot air into the system. Replaced the old box with one off a C-150 and the problem is cured.
Thanks, again, for all the help.
Alex
Thanks, again, for all the help.
Alex