BadMooneyRising Posted November 26 Report Posted November 26 I was working with my mechanic the other day to swap out the steering horn (newer style) on my 1974 F model. The plane has a very aggressive shimmy after landing when slowing down to about 20 kts, and will also shimmy if you taxi fast enough. So that's ultimately what we're trying to address. After putting the plane on jacks and removing all the necessary bolts and linkages, we hit a deadend when we weren't able to remove the Shaft Assembly. We thought it would slide right out, but it seemed like it was getting held up somewhere. Does anyone know what we did wrong? Does the entire nose gear need to be dropped to perform a complete swap of the steering horn? Quote
Marc_B Posted November 26 Report Posted November 26 @BadMooneyRising The nose wheel is sensitive to the fore-aft position. Sometimes with new shock discs this pushes the nose wheel forward which makes it way more twitchy. Check the plumb line and adjust either the collar or Mooney also has a thin spacer (washer) that you put at the top of the tack to compress the gear more and push the nose wheel further aft. 1 Quote
Marc_B Posted November 26 Report Posted November 26 https://web.archive.org/web/20190207032823/http://donmaxwell.com/the-eight-second-ride-sb-m20-202/ Here is the Mooney SB. https://mooney.com/wp-content/uploads/2020/12/SBM20-202.pdf Quote
N201MKTurbo Posted November 26 Report Posted November 26 I believe if you retract the gear, the steering horn can be dropped off its pivot. A picture would help. 1 Quote
Ragsf15e Posted November 26 Report Posted November 26 28 minutes ago, N201MKTurbo said: I believe if you retract the gear, the steering horn can be dropped off its pivot. A picture would help. I want to say my mechanic retracted it halfway to work on the nose gear. Either that or he was punishing me for doing something stupid as he disconnected the gear from the motor and then had me holding the mains up about halfway and then said don’t move. I swear he went for coffee. Fully retracted is probably easier… 2 5 Quote
Utah20Gflyer Posted Thursday at 10:52 PM Report Posted Thursday at 10:52 PM In my case I removed the lower cowling to get better access to the steering horn. With the lower cowling in place it is really tight. Not sure which way you are trying it. Quote
AJ88V Posted Friday at 10:00 PM Report Posted Friday at 10:00 PM Recommend you check your tire pressure before doing anything else. Mine definitely shimmies worse when the tire pressure is low. Not meaning to start an argument, but typically keep my nose gear tire more like 35 psi than 30. 1 Quote
Ragsf15e Posted Friday at 10:07 PM Report Posted Friday at 10:07 PM 5 minutes ago, AJ88V said: Recommend you check your tire pressure before doing anything else. Mine definitely shimmies worse when the tire pressure is low. Not meaning to start an argument, but typically keep my nose gear tire more like 35 psi than 30. I want to say my poh shows like 49psi for the nose? 30 for mains? 1 Quote
65MooneyPilot Posted Friday at 11:05 PM Report Posted Friday at 11:05 PM Mooney models: C,D,E are 30 PSI All wheels. F models 30 psi mains 49 psi nose wheel. These are pre 1966 Mooneys. As always check the manual for your Mooney. 1 1 Quote
AJ88V Posted Saturday at 10:40 AM Report Posted Saturday at 10:40 AM 11 hours ago, 65MooneyPilot said: Mooney models: C,D,E are 30 PSI All wheels. F models 30 psi mains 49 psi nose wheel. These are pre 1966 Mooneys. As always check the manual for your Mooney. Yep, good advice to CHECK THE POH. (Didn’t realize the F was that high!) That said, my nose wheel def shimmies when the tire pressure is low, so worth double checking that if yours is shimmying. Quote
65MooneyPilot Posted Saturday at 01:44 PM Report Posted Saturday at 01:44 PM I personally don’t get wrapped around the axle about the tire pressure unless it is below the book value. I personally put in a few extra psi because tire pressures change with outside air temp. Using nitrogen is way better but I am not. As far as nose wheel shimmy’s go a lot of owners suspect loose steering for a shimmy problem. In my case my nose wheel gear was severely worn out. I jacked up the plane and I could move the whole nose gear vertically a half inch. I took it off and sent it in to LASAR and they sent me an upgraded rebuilt one. After installing it, it was like having a new plane. Super smooth taxiing, taking off or landing. Quote
M20E for me Posted Sunday at 05:30 PM Report Posted Sunday at 05:30 PM I had never felt a nose gear shimmy until last Friday. After landing and exiting the runway I receive taxi instructions right after hearing the ground controller give clearance to someone else to taxi the opposite direction towards me from the other end of the taxi way. This is normal procedure and they will tell each plane to taxi on the right side of the taxi way. I normally taxi between 15-20mph when the controller asked me to expedite my taxi. I obliged and got up to about 35mph and after about 15 seconds something set off the nose gear and it started a violent shimmy. I’ve had the 65 M20E for 3 years now and had never felt the slightest shimmy. Stepping on the brakes and slowing down made it go a way but it took a few seconds. Something to keep my eye on. Quote
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