Aileron control link rubbing

[PT20J]

During annual inspection, I noticed a rubbing noise emanating from within
the left wing during the last inch or so of the left aileron travel in the
up direction. Some investigation revealed that the sound comes from the
aileron control link rubbing on the aft side of the phenolic guide block at
wing station 133.0. The paint on the tube is rubbed off, but the tube
appears undamaged and there is no metal-to-metal contact. I cleaned all the
wing guide blocks and regreased with Aeroshell 7 to no effect. The right
aileron does the same thing to a lesser extend, but I haven't opened up the
right wing yet to verify that it's the same guide block. I'm wondering if
anyone else has experienced this and found a way to correct it.

[Mooneymite]

If you are referring to the aileron control link covered by an AD, yes.

After complying with the AD, all seemed well, but on the next annual, I discovered exactly what you describe.  I contacted Mooney about the issue since I had bought the compliant link from Mooney.  The chap on the phone had me send the rubbing link back and he sent out a new link.  He opined that during the time when everyone was scrambling for compliant links that one of the vendors "let his tolerances slip" and mine was apparently not "in tolerance.

As with your situation, it was rubbing, but there didn't seem to be any damage, or restriction.  Just a rubbing noise.  However, after paying what Mooney charged for the link, I wanted it to be "right".

Was your link modified "in house" to comply with the AD, or was it bought new?

[N201MKTurbo]

How did you grease the guide blocks? 

I rub grease into the rod and the guide block. Lift the rod off the guide block so you can work the grease into the phenolic. Have someone run the ailerons back and forth while you are looking and listening to see that it is running smoothly.

[RobertGary1]

I believe Mooney calls for Lubriplate on the blocks, not grease. 

-Robert

Edited September 10, 2018 by RobertGary1

[MB65E]

A/S #7. Or MIL-23827.

-Matt

 

[PT20J]

There are two pertinent Mooney Service Bulletins:

M20-264 (AD98-24-11) to replace aileron control links with gusseted parts. This was done on my airplane in 1998 by installing the Mooney factory kit.

M20-289A to change spacers in the links to prevent interference with the landing gear bellcrank. This was done on my airplane in 2005.

Since I recently purchased the airplane, I have no way of knowing how long this rubbing has been going on. It occurs at wing station 133.0, and looking more carefully at the IPC, I see that the tube is actually called AILERON CONTROL TUBE ASSY at that point rather than a CONTROL LINK (the control tube bolts to, and is an outboard extension of, the control link). I've attached a picture of the rub point with most of the grease wiped off.  Next thing to check is that the spacers are correctly installed per M20-289A.

The Service Manual calls for using MIL-G-23827 grease on the guide blocks. Traditionally this was Aeroshell Grease 7. This grease spec. has been superseded by MIL-PRF-23827C which specifies Type I (metallic soap thickener) and Type II (clay thickener) greases. The two types are not compatible. Aeroshell 7 is Type II. I found  evidence of at least three different greases having been used on my guide blocks. I cleaned it all off with Stoddard solvent and regreased with Aeroshell 7. It only requires a thin coat. There really isn't any way to hold a lot of grease around the thin phenolic blocks, and forcing a lot of grease in there just makes a mess that collects dirt.

Skip

[MB65E]

Thanks for re-posting the type 1 and type 2 issues. I always Lable my grease guns with the product as well as the type 1 or 2. Aeroshell 33 is the other grease that meets the C requirement but is a type 2 grease. Both don’t mix. 

What you’ve done is about all you can do. Now that it’s lubed you shouldn’t have issues. It was probably dry for some time whiched caused the paint to rub away. 

That 289A SB is a little tricky. I ordered the kit for the SB on mine, and it actually prevented movement slightly. I’ve found Teflon washers to be helpful as well. 

-Matt