Lawson Laslo
Pre-takeoff checklist
- Joined
- Jan 18, 2019
- Messages
- 403
- Location
- Sundance airport Oklahoma
- Display Name
Display name:
N2005H
Hello, The annual inspection was completed last week on the O-200 powered ercoupe, it took just under a month due to having to order parts etc... anyway after the annual inspection we took it for a flight and everything ran fine until we were practicing slow flight with carb heat on since it was a moist morning and when i went to add power the engine stumbled and wouldn't go above 2,000 rpm so we went back and landed. Second flight we just taken off (no carb heat) and were on crosswind and the engine went down to about 2000 rpm running very rough I throttled off and making tailwind landing and when i went to add throttle it ran better again. My mechanic never adjusted anything on the carburetor during annual. Still not sure what the issue was, today i went and did some full power ground runs with the following results
First run i went to full power with full rich mixture, it ran fine (2600 rpm) till i turned carb heat on and the RPM went down to about 1800-2000 rpm at times 1500rpm and was extremely rough. I put carb heat off and it still ran rough and wouldn't go over 2200 rpm. I then lean the mixture out and the engine then ran like normal
Second time I Started with mixture leaned out and then went full power and was steady at 2,600rpm which is normal i then applied carb heat and only had a 50-100rpm drop and engine was still smooth.
Ive never had this issue before. I am thinking that maybe after time the idle air mixture vibrated and made the mixture to rich? the weird thing is that in May before the annual it was running perfect and now in July its not running properly, maybe its because the high heat 90+degrees and density altitudes over 4000 feet (ground level at HSD is 1,200')
let me know if you think its the idle air mixture screw or maybe something else.
Thanks
First run i went to full power with full rich mixture, it ran fine (2600 rpm) till i turned carb heat on and the RPM went down to about 1800-2000 rpm at times 1500rpm and was extremely rough. I put carb heat off and it still ran rough and wouldn't go over 2200 rpm. I then lean the mixture out and the engine then ran like normal
Second time I Started with mixture leaned out and then went full power and was steady at 2,600rpm which is normal i then applied carb heat and only had a 50-100rpm drop and engine was still smooth.
Ive never had this issue before. I am thinking that maybe after time the idle air mixture vibrated and made the mixture to rich? the weird thing is that in May before the annual it was running perfect and now in July its not running properly, maybe its because the high heat 90+degrees and density altitudes over 4000 feet (ground level at HSD is 1,200')
let me know if you think its the idle air mixture screw or maybe something else.
Thanks