Sabremech Posted April 18, 2016 Report Share Posted April 18, 2016 It's been difficult to get the Johnson bar in the down lock for a while . I replaced the down lock a year or so back and it was difficult to get in the lock position. I decided it was time to fix this problem once and for all. I took the nose out of the equation today and found some interference with a bracket under the floor. Has anyone else experienced this with theirs and if so, what was your remedy? I attached a photo of the Johnson bar and where it's contacting. Thanks, David Quote Link to comment Share on other sites More sharing options...
N201MKTurbo Posted April 18, 2016 Report Share Posted April 18, 2016 That all could benefit from a good cleaning and reprinting. Those parts should be lubed at every annual. When you take it apart to clean and paint, you can check the condition of the bearings and fasteners. Quote Link to comment Share on other sites More sharing options...
1524J Posted April 18, 2016 Report Share Posted April 18, 2016 When we had our interior redone the replacement carpet was too thick and we had a hard time locking the J bar. The tolerance is tight. I can't make out the orientation from your photo. Quote Link to comment Share on other sites More sharing options...
Sabremech Posted April 19, 2016 Author Report Share Posted April 19, 2016 1 minute ago, N201MKTurbo said: That all could benefit from a good cleaning and reprinting. Those parts should be lubed at every annual. When you take it apart to clean and paint, you can check the condition of the bearings and fasteners. Definitely could use a cleaning and most of this is dirt and grime from having plenty of lube. I'll clean it but not going to take it any further apart than necessary at this time. Painting will happen when I take the airplane down for paint. Hi 1524J, this is looking up from the bottom of the airplane at the Johnson bar. Carpet and boot aren't visible from this angle. Thanks, David Quote Link to comment Share on other sites More sharing options...
Sabremech Posted April 19, 2016 Author Report Share Posted April 19, 2016 After looking in the IPC, I suspect I have worn bushings on the Johnson bar itself. Will be ordering new bushings tomorrow. I want to be back up and flying by the weekend. Quote Link to comment Share on other sites More sharing options...
takair Posted April 19, 2016 Report Share Posted April 19, 2016 Can't quite get oriented in the photo. Will be curious what you find. It seems that every couple of years I am adjusting the preload and it seems to get a little harder to lock in place. Will be doing my steering linkage soon and was going to take a look at this myself. Keep us posted on what you find. Quote Link to comment Share on other sites More sharing options...
Bob_Belville Posted April 19, 2016 Report Share Posted April 19, 2016 I've never had to adjust the gear preload and I'm pretty sure Don Maxwell says that once that adjustment is done correctly it should not change. Quote Link to comment Share on other sites More sharing options...
Bob_Belville Posted April 19, 2016 Report Share Posted April 19, 2016 David, are you talking about the down lock against the panel or the up lock on the floor? I ask because a mention was made of carpet thickness which is indeed a potential issue but it affects what I'd call the up lock. In my plane the bar is tightest to the floor right behind the hole where the bar comes through the floor. 1 Quote Link to comment Share on other sites More sharing options...
Sabremech Posted April 19, 2016 Author Report Share Posted April 19, 2016 Hi Bob, The down lock on the panel is where my issue is. My picture is from underneath the airplane looking at the Johnson bar hitting on an aileron linkage bracket. 1 Quote Link to comment Share on other sites More sharing options...
Bob_Belville Posted April 19, 2016 Report Share Posted April 19, 2016 4 minutes ago, Sabremech said: Hi Bob, The down lock on the panel is where my issue is. My picture is from underneath the airplane looking at the Johnson bar hitting on an aileron linkage bracket. Do you associate the problem with the new receptor? Can the block be adjusted, perhaps shimmed? (I have not studied that assembly even though I just replaced all 3 control cables and spent several hours right beside it, drilled out the hole for the throttle and mounted the gear alert limit switch! Quote Link to comment Share on other sites More sharing options...
takair Posted April 19, 2016 Report Share Posted April 19, 2016 1 hour ago, Bob_Belville said: I've never had to adjust the gear preload and I'm pretty sure Don Maxwell says that once that adjustment is done correctly it should not change. I'll have to pay more attention to this. It's possible that I'm just haunted by this when I am doing other work, like trying to get gear doors closed and symmetrical or changing other worn parts. Quote Link to comment Share on other sites More sharing options...
Andy95W Posted April 19, 2016 Report Share Posted April 19, 2016 David- not sure if it helps, but there is a SB that applies to the aileron links interfering with the gear mechanism at full extension: http://www.mooney.com/en/sb/M20-289A.pdf Good luck! 1 Quote Link to comment Share on other sites More sharing options...
1964-M20E Posted April 19, 2016 Report Share Posted April 19, 2016 I had an issue like this on my former E and once I got under the plane and lubed things up I didn't have any more issues. Any moving part sliding part pivoting part got lubed including bungee springs from the gear doors to the J-bar. Quote Link to comment Share on other sites More sharing options...
mike20papa Posted April 19, 2016 Report Share Posted April 19, 2016 With the AC up on jacks, you could disconnect the links from the gear and see if that allows the bar to go easily into full lock down position. Or, you could also check to see if the preload is set to high. This can be easily done by simply checking to see if you can rotate (by hand) the gear actuation tubes that you adjust for the preload. Typically, if the Heims are so stiff, you can't rotate them by hand when the gear is down, then the J bar will be difficult to get to lock full down - without "slamming" the bar forward when the gear swings down. If this is not the problem, then you probably do have an issue with carpet or the boot not providing enough clearance between the j bar and the nose wheel well. Joe 1 Quote Link to comment Share on other sites More sharing options...
Andy95W Posted April 19, 2016 Report Share Posted April 19, 2016 Also, David- I highly recommend LASAR for landing gear bushings. They make their own PMA'ed bushings that are less expensive and more durable than factory. They also have PMA'ed oversized bushings in case your fittings are worn. Quote Link to comment Share on other sites More sharing options...
MB65E Posted April 19, 2016 Report Share Posted April 19, 2016 Thanks 95W, After always being at the minimum tension for the last 3 years, I recently increased my Main gear tensions. That actually loosened the nose tensions. Tightened the nose. Then adjusted the gear doors to be tight. Then the left gear door rubbed on the gear when it was off jacks. Flew it that way for a month. Bugged the snot out of me. Thought I might check the up limits, they were good, almost touching the stops. Finally, I adjusted the clamps that the gear door rods attach to. About 1/4 in. This really improved the geometry of the gear doors. I have not seen any adjustment procedure on the brackets, but the gear works great now. Just putting it out there due to the lack of data I Had. My gear is now tight, the only loose spot is on one of the left MLG links. The Belcrank that bolts into the wing and is saftety wired appears to have a couple thousands play compared to the right MLG. Are the bushings in the over center link and belcranks in the MLG replaceable? -Matt Quote Link to comment Share on other sites More sharing options...
Andy95W Posted April 20, 2016 Report Share Posted April 20, 2016 Matt- yes, very replaceable, fairly simple. I just did mine last year. The only hard one is the forward main pivot point for the gear truss itself. With everything tight, you'll have to re-rig the gear again. Good thing you're in practice! Quote Link to comment Share on other sites More sharing options...
Sabremech Posted April 21, 2016 Author Report Share Posted April 21, 2016 Made a little progress tonight on the gear issue. The preloads were good but will be redone after fixing this problem. The bar is not hitting the aileron linkage fitting as I had a picture of in a previous post. It's tight, but I have .006 clearance there, so that's not the problem. I don't have any carpet near there on my airplane as it's a plastic panel on the floor around the j bar. I do have interference with the plastic trim panel forward of the handle and over the nose gear well. I'm still suspicious of the 2 bushings for the J bar and where it attaches to the fuselage, so I ordered 2 new ones from LASAR today. I hope to work on it again over the weekend and finally find out whats holding the bar back from the down lock. Getting closer to solving the mystery. David 1 Quote Link to comment Share on other sites More sharing options...
Sabremech Posted April 22, 2016 Author Report Share Posted April 22, 2016 I found the problem with the Johnson bar today, it's bent. It was difficult to see until I put a straight edge on it and then it was obvious. I plan to get it straightened and hopefully back in the air by next weekend. David Quote Link to comment Share on other sites More sharing options...
mooniac15u Posted April 22, 2016 Report Share Posted April 22, 2016 10 minutes ago, Sabremech said: I found the problem with the Johnson bar today, it's bent. It was difficult to see until I put a straight edge on it and then it was obvious. I plan to get it straightened and hopefully back in the air by next weekend. David The bar itself is bent or something under the floorboards is bent? Quote Link to comment Share on other sites More sharing options...
Sabremech Posted April 22, 2016 Author Report Share Posted April 22, 2016 44 minutes ago, mooniac15u said: The bar itself is bent or something under the floorboards is bent? The bar itself. I talked with Don Maxwell about the problem and after I identified it this morning gave him a call back and they've seen them bent all different ways. Mine is bent back away from the down lock which caused it to hit the shroud around the fuel line (under the floor) from the right wing and push it into the nose wheel housing. I will get it straightened as it's not bent much but enough to have made getting it in the lock a real pain. David Quote Link to comment Share on other sites More sharing options...
Bob_Belville Posted April 22, 2016 Report Share Posted April 22, 2016 20 minutes ago, Sabremech said: The bar itself. I talked with Don Maxwell about the problem and after I identified it this morning gave him a call back and they've seen them bent all different ways. Mine is bent back away from the down lock which caused it to hit the shroud around the fuel line (under the floor) from the right wing and push it into the nose wheel housing. I will get it straightened as it's not bent much but enough to have made getting it in the lock a real pain. David Very interesting! I wonder if there is anything Mooney that DMax hasn't seen? Multiple times. Quote Link to comment Share on other sites More sharing options...
takair Posted April 22, 2016 Report Share Posted April 22, 2016 1 hour ago, Sabremech said: The bar itself. I talked with Don Maxwell about the problem and after I identified it this morning gave him a call back and they've seen them bent all different ways. Mine is bent back away from the down lock which caused it to hit the shroud around the fuel line (under the floor) from the right wing and push it into the nose wheel housing. I will get it straightened as it's not bent much but enough to have made getting it in the lock a real pain. David Wow. Any theory on how it might get bent? Seems sturdy... Quote Link to comment Share on other sites More sharing options...
Bob_Belville Posted April 22, 2016 Report Share Posted April 22, 2016 27 minutes ago, takair said: Wow. Any theory on how it might get bent? Seems sturdy... Since the normal issue is getting the bar to seat in the floor socket (gear up) due to the close fit to the floor right behind the hole (thick carpet makes it tough) I can visualize that raising the gear with a belt buckle or some other stray object on the floor between the seats could provide a fulcrum that might permit the tubing to be bent in the plane that's giving David his problem. IOW, put a smart phone or a belt buckle right behind the JBar and push down hard on the bar trying to get it to the floor... anyone want to get a confession off your conscience here? Quote Link to comment Share on other sites More sharing options...
Pictreed Posted April 22, 2016 Report Share Posted April 22, 2016 25 minutes ago, takair said: Wow. Any theory on how it might get bent? Seems sturdy... Good question. A buddy said he was flying with his grand daughter in the back and she kicked the gear lock and it slammed the gear down with a very load bang...maybe something similar? Quote Link to comment Share on other sites More sharing options...
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