Hawth200

I did not notice a drop in MP.

The relative humidity wasn't all that high, but the carb temp was in the caution range. I probably should have kept with the carb heat a bit longer, but the EGT through me for a loop. I wouldn't expect high EGT to be a symptom of carb ice. An engine analyzer is definitely on my wish list... I would have loved to been able to see what all the cylinders were doing. Thanks for all the comments, I love this forum!

Troy, Yes, I could have done an in flight mag check, much like you do during your typical run-up on the ground. I did do a quick run-up when I got on the ground before shut down and everything checked normal.

I suppose that's a possibility. I just find it hard to believe that a plug could load up like that with a cruise power setting about 1.5 hours into the flight. All of my plug fouling experiences have been from idling on the ground. I guess it could happen though. In hind sight, I wish I would have done a mag check. It sure was rough! If it had continued much longer I would have landed ASAP

I didn't run carb heat very long. Probably no more than 10-15 seconds. I noticed no change in MP

Yesterday, while cruising at 6500', my carbureted O-360 started running very rough (like I had lost one cylinder) and I noticed that the single cylinder EGT indicator was indicating about 100 degrees higher than normal. The CHT was indicating normal. I figured that the mixture setting had become overly lean, so I began to enrichen the mixture. The change in mixture made no difference in the rough running engine and strangely the EGT indicator did not react to the change in mixture. The fuel pressure was normal. I did not switch either magneto off, but decided to next apply carb heat to see what effect that would make. With carb heat applied, the engine began to stumble even worse and did not clear up. From that, I figured that I now must be running an overly rich mixture setting. I began to lean the mixture back out ignoring the EGT indicator that was still reading about 100 degrees high. As I leaned the mixture the engine began to run smoothly again. I kept my eye on the EGT indicator. It continued to read 100 degrees high for a few minutes before settling back to normal. The engine operated normally for the rest of the flight (about 40 mins). While it felt like an eternity, the roughness probably didn't last more than 3 or 4 minutes. I'm just trying to come up with a reasonable explanation for this. My first thought was that I may have experienced a sticky exhaust valve... I just thought I would mention it here to see if anyone had any possible explanations. Thanks! Seth

Okay. Thank you for clearing that up for me!

Okay, I see... Thanks for posting a picture. It looks like countersunk screws are used which is going to involve dimpling the cowling. Do you know if nutplates where installed on the light housing or are there just some sort of nut clip used. Thanks again.

I have a question about the landing light lens cover STC that is available for our older Mooney's. On my C model the landing light lens housing is riveted to to cowling and the landing light bulb is replaced from the front. Originally I was under the impression that the new lens cover was sandwiched in between the cowling and the light housing and rivets re-installed. But obviously this cannot be the case if the bulb is replaced from the front. So, it is hard to tell from the pictures that I have seen, but is the new lens held in place by new screws and clip nuts/nutplates after the rivets are removed?