Nose Gear Noises

[Marauder]

Since I have owned my 1975 F, I have always heard a little bit of clunking from the nose gear when crossing bumps. I have mentioned it to mechanics over the years and none have have found anything loose or worn on the nose gear. After having my donuts replaced this past annual (a couple of months ago), I have noticed the clunking was louder than before. My IA says he heard it as well after replacing the donuts. He thinks it is the mechanic stop. He, like the other mechanics who have looked at it, never nailed a cause. Do any of you hear this? I don't think it is normal, but can't nail down the cause... Any thoughts?

[MooneyMitch]

Hi Marauder.

 

You might check your nose gear lower leg attach bolts/bushings [two bolts/bushings total, one left and one right]. 

 

With the nose off the ground, grab the front wheel and try to move it side to side and front to rear.  If those bolts/bushing are worn, the lower leg will move just a bit and you can see it at the joints.

 

Doesn't take much movement of that lower leg to get that clunk sound when you cross even a small bump.

 

Please let us know what you discover.

[Marauder]

Hi Marauder. You might check your nose gear lower leg attach bolts/bushings [two bolts/bushings total, one left and one right]. With the nose off the ground, grab the front wheel and try to move it side to side and front to rear. If those bolts/bushing are worn, the lower leg will move just a bit and you can see it at the joints. Doesn't take much movement of that lower leg to get that clunk sound when you cross even a small bump. Please let us know what you discover.

Thanks Mitch! I'm fishing for ideas since this issue has been going on a while and it has stumped a bunch of chumps My obvious concern is the nose gear collapsing, but as I mentioned, it has been this way for years and no one seems to be concerned -- except me. And it sounds from your answer that this is not "normal"...

[1964-M20E]

Look at the retraction link bushing I have seen where these wear.  If you take the top of the nose wheel and try to roll it fore and aft you can see how much play is in the retraction link.  Unfortunately you need to replace the link and the bushings when you have this due to the design both parts will wear.  Once one part starts to wear it will cause more stress on others and cause them to wear as well. 

This is a very good pre-buy check and the plane does not need to be on jacks.  Also check the nose pivot truss for play.  It could be in the nose pivot truss as well.  I replaced these on mine at annual and my noise has gone away.  The plane will fly with significant amounts of play in these parts but eventually the play will bite you.

[Marauder]

Look at the retraction link bushing I have seen where these wear. If you take the top of the nose wheel and try to roll it fore and aft you can see how much play is in the retraction link. Unfortunately you need to replace the link and the bushings when you have this due to the design both parts will wear. Once one part starts to wear it will cause more stress on others and cause them to wear as well. This is a very good pre-buy check and the plane does not need to be on jacks. Also check the nose pivot truss for play. It could be in the nose pivot truss as well. I replaced these on mine at annual and my noise has gone away. The plane will fly with significant amounts of play in these parts but eventually the play will bite you.

Thanks for the additional items to check. Based on what said, you had the noise as well. I wonder how many others like me have this noise and think it is normal. All I do know is that it is louder now with the new donuts.

[Marauder]

When I purchased my M20B as a gear-up repair job, I went through the landing gear with a fine-tooth comb. I replaced EVERY bushing and Heim bolt from the Johnson Bar forward. I also installed the oversized LASAR steering bushing, but did not opt for the updated LASAR steering linkage yoke assembly, as I went with replacing the original Heim bearings instead. After performing a proper rigging procedure with a dial torque wrench (and using updated rigging torque values), I found the M20B still clunks on the front wheel going over small bumps. I guess the accumulated "slop" from the series of Heim bearings adds to the occasional noise and that's the way it is. Ph il Mc C ANdlE.ss

Thanks Phil. I am curious how many others have this nose wheel noise. Where is 201er when you need a good poll?

[N201MKTurbo]

When you hit a bump the overcenter link will fully extend, coming off of the over center position. When it goes back to the overcenter position you hear the clunk. It is nothing to worry about and cannot be fixed. If you have the plane up on jacks pull the nose wheel down and forward you will see the overcenter link go from its slightly bent position to compleatly straight. When you release the wheel it will go back overcenter.

[N201MKTurbo]

BTW, this happens on the rebound from bump, not from hitting the bump.