SuperDaggi

Ok, we spent the best part of yesterday morning trying to figure this out. Wiggled the cowl flaps and the left one moved a little more than the right one - but there was no significant difference when compared to another M20J we had there. Actually, the cowl flaps on the other one had more wiggle room. Then, took the mechanism apart (at least the lower part) and looked if there was something that was worn. There was a little wear but nothing significant enough to explain the problem. Then, by coincidence noticed that the exhaust mount attaching the exhaust to the frame outside of the cowl flap was missing a nut…! Was behind the exhaust pipe, so only visible when lying under the plane. Attached a nut, rigged the cowl flaps to make sure they're in line with the service manual and went for a test flight. Problem gone! Looks like opening the cowl flaps released the exhaust pipe and the horrific noises were caused by the screw moving within the mount. Thanks for all the great tips and the help!!!

No idea what an AMU is but my previous owner left it open and I ended up with about 1k in cost to get it fixed. The replacement shipped required a lot of manual labor to make it fit. Plus, the door steward also punched out and that was another couple of hundred to replace.

Done by my local shop who have a lot of Mooney business, so I'm certain they know what they're doing.

Starts pretty much immediately after I apply full throttle for take-off. Didn't notice much of a speed-related difference. Feels like lowering RPM helps a little but it never goes away until I close the cowl flaps. I close them, it's all gone and back to normal. Baffle integrity should be fine but probably worth another close look.

Thank you! Some good tips, will check on these items. Temp issues are somewhat weird and depending on who you ask, it's a non-issue. Factory oil temp is always in the green, EDM shows temps in the area of 210+F and will sometimes even rise beyond 220F. As I approach 220F, I can see the oil pressure declining and it'll be in the lower 60s on the EDM, touching the yellow on the factory gauge. Oil is 15W-50. Factory oil temp still shows me in the green though and I've seen Youtube videos of people flying M20J, where their oil temp gauge is actually showing a higher temp than mine, even with low power in approach. What is noticeable is that the oil temp on a cold engine warms up very quickly. Typically by the time I reach the runway, oil temp is sufficient for departure. Recently changed from ROP to LOP and have been able to keep the oil temp below 210F doing that, depending on OAT even as low as higher 190s. While we did a big investigation into this, even replacing the oil cooler and vernatherm, I am starting to question if I really have an issue or if I just need to manage oil temp properly using cowl flaps, LOP and power settings.

Been struggling with an issue with my cowl flaps and the situation just worsened… No idea where to even look for the root cause. If I open my cowl flaps (can only fully open or fully close), I get huge vibrations to the point that I see my entire cowl move from within the cockpit. Also sounds terrible, well beyond the usual loudness of open cowl flaps... If I close them, then it all stops and goes to normal. No more vibrations, no more cowl movement. This happened after we replaced the hinges for the cowl flaps, so I guess we found out why the previous ones were worn out... I guess their wear somewhat prevented the vibrations from getting the best of the lower cowl. Now, I'm wondering what may be causing these vibrations? The hinges are solid, the cowl flaps don't move around much if I try and wiggle them when they're open. Cowl flaps closed, all good, no vibrations or any weird sounds. Been also having issues with oil temp that I could keep under control opening the cowl flaps until I reach ambient temperatures that do the trick. Now, it doesn't seem like much of an option to keep them open that long. Looking at another M20J, I noticed the left cowl flap looks different from mine (mine is flat, this one looks pretty much like the right one being bent around the exhaust). Wondering if that may help with oil temps?

Guys, thank you so much! I have done as instructed and put myself in there until I finally figured out what was making the sound and causing the resistance. Turns out it was the control bar going through a kind of fairing in the panel. Really only required some lubrication... Gotta admit, it felt and sounded like something much worse.

Hi, My M20J 201 has a weird resistance at a specific point when pushing the yoke all the way forward and I can also hear a sound that seems to come from behind the panel when I overcome that resistance. Is that normal? This doesn't occur in the range of movement I would normally do on the yoke, it's well beyond, probably somewhere like halfway forward.