In taking the recommendations of the ABS and others about replacing the nose gear rod-end bearings, I took these to heart and did mine during the annual inspection on my bird which is just wrapping up. All of the nose gear rod-end bearings, bushings, and hardware have now been replaced.

We found an anomoly in the rod assy, fwd nose gear retract link as shown in the attached pictures. What caused it, I have no idea, but can only surmise that the previous owner who was learning to fly in the plane must have had a nose wheel first hard landing. Again, I just don't know, and can only speculate as to what might have caused the sleeve to split like this.

I also found one rod-end bearing that had a crack across the crown, and down one side towards the bolt hole. I know that it would have eventually failed, but when is the question.

Thanks to the ABS and the others preaching on the need to replace the rod-end bearings, I found these two potential failure points before they did fail and result in unpleasant results to our pride and joy as well as ourselves and/or potentially others.

Ron

Wow, good catch. Was it very expensive to fix?

Ken,

The gurus say at 4000 hours TT all landing gear rod ends and bushings should be replaced. Failure can be terribly costly.

We did ours so we're good for another 4000 hours. We found no issues.

What TT is on your airframe?

Hi Ron,

Good catch and thanks for sharing your find!

May I add your pics and details to the rod end page here at CSOBeech.com?

http://www.csobeech.com/gear-rod.html

As you can see, others have added their "shocking but true" finds when digging into their rod end changeout and hopefully, these finds will encourage owners to pre-emptively change their rod ends and inspect all the other components of this airframe-saving system

Let me know.

Thanks.

Mike

Jim:

I'm looking for my notes, but the ABS tech support folks said that the rod-end bearings, bushings, etc. on the nose gear should be replaced at 2,000 hour intervals. My N35 has 2,462 hours on it. Most of the information I've gotten from the ABS and shops indicate that the main gear rod-end bearings almost never fail, but the nose gear ones are the problem at some level above 2,000 hours. Thus, the 2,000 hour recommendation.

As to the expense, the good folks at Avstat had a complete new rod assy (P/N 35-825087-16) that was substantially cheaper than RAPID's price as it was NOS. This complete assy has the braze, plunger, spring, and rod-end bearing included. I don't scrimp on safety related issues, but I will look for the best legal value.... Kind of following Mike Caban's CSOB philosophy.

Regards,
Ron

Mike:

Yes, please feel free to use the pictures and narratives to hopefully help others increase their knowledge for maintenance and safety on their birds. I will post one more picture which will show the complete rod assembly, forward nose gear retract link (P/N 825087-16) old and new.

Regards,
Ron

Thanks Ron.

Looking forward to the other pics.

Just to clarify, is P/N 825087-16 the nose retract rod cross shaft? And you sourced it from Avstat?

Thanks,

Mike

Ron,
Was there anything to see on visual exam or was the defect found only after removal? Sorry, but I'm not sure what I'm looking for. In other words, are you guys suggesting that this is a pending problem that could catch any of us onawares despite aggressive inspections?

If you read ABS's recomendations they mention to change them at 2000 hours or "on Condition" I just changed mine at 4400 hours and from (1978). There was nothing wrong with them. no corrosion, no wear, no cracks. But I guess the peace of mind was worth it. I also learned alot about the landing gear these last few weeks. I bought the ABS landing gear book, and changed the rod ends myself under the supervision of an IA. I also changed the landing gear actuator oil seals and bearings. and re installed. There is a lot of stress on all of the landing gear rods. It is designed using the opposite of leverage, where a small movement in the linkage moves the gear. You almost need to remove the rod ends to really determine if they are moving smoothly and with any wear. I guess if you do that you might as well change them. If they have been lubricated regularly I cant imagine it being an emergency.though. My $.02

Mike:

This part number is for the whole enchilada (rod assy, fwd nose gear retract link).

In the N35 parts manual, it's on PDF page 247, Figure 39, includes index #'s 10 (braze assy), 11 (plunger assy), 12 (spring, nose gear retract compression), and all the following hardware down to, but not including index #13.

Yes, I did get it from Avstat, but Arrell has it, and RAPID says that it is a current production part #.

Greg:

The defect would have been almost impossible to see with a normal visual inspection. With the part on the aircraft, the split would have been oriented straight up towards the bottom of the nose wheel keel compartment. I guess if you were to make a special effort to inspect the top of this part and used a mirror and good lighting, then you could have found it.

I try and do a really good inspection of the landing gear every month, and did not find/see it. The only reason I found it was because the rod had been removed as part of the rod-end bearing replacement process.

The great thing about this forum and the ABS forums is that this information can be shared, and others can benefit from it. I will definitely add this to my own personal check list for inspection from now on.

For personal curiosity, I just want to know: (a) what caused this damage, (b) why it went the entire length of the sleeve, and (c) why it wasn't addressed about 10 years ago, which is when I suspect this damage occurred.

Regards,
Ron

Here are a couple more pictures from today.

This is what the rod assy with the damage looks like removed from the airplane.

This is how the damaged braze assy looks like with the compression spring installed.

I think that someone would really have to be looking for this damage to find it on the airplane....

Ron

Remember, the inner shaft (forward section) extends far enough down the tube so that if the pin shears, the nose wheel will hang in the wind, but the rods will still interface enough to extend gear properly. This was changed with s/n D-4547

Could be a previous mechanic felt it was safe as is.

Thanks guys!

I will add this additional info and picture to the rod end page at

http://www.csobeech.com/gear-rod.html

Give me a few minutes.

Mike