Lubricant for the yoke connection

[ArrowFlyer86]

When I get my plane (PA28R) back from annual each year the shaft connecting the yoke is always well greased with virtually no friction giving the controls a nice, new frictionless feel. Now I'd kind of like do that maintenance myself periodically b/c after 150h it's not as nice...

Curious is there a specific lubricant I should use for that - or can I use whatever?

For clarification, this is what I'm talking about:

 

[Bell206]

Curious is there a specific lubricant I should use for that - or can I use whatever?

FYI: some lubricants don't work as well when mixed. Perhaps find out what your APIA uses (and method) and stick to that.

 

[Lon Stratton]

This is from my PA32 maintenance manual.

 

[Dan Thomas]

Never use grease. It attracts dust and forms sticky sludge that could cause control problems.

I always cleaned that shaft off with non-chlorinated brake cleaner. Sometimes I had to work it into the bushing in the panel and loosen up the crud in there and blow it out. The crud comes from skin oils from pilots' hands. I used dry silicone spray lube. Sprays on wet, then dries. Slick, and no dust attractant.

 

[ArrowFlyer86]

View attachment 113937 This is from my PA32 maintenance manual.

Thanks! I need to get the maintenance manual for mine. I only have the POH and a separate operating manual.

Never use grease. It attracts dust and forms sticky sludge that could cause control problems.

I always cleaned that shaft off with non-chlorinated brake cleaner. Sometimes I had to work it into the bushing in the panel and loosen up the crud in there and blow it out. The crud comes from skin oils from pilots' hands. I used dry silicone spray lube. Sprays on wet, then dries. Slick, and no dust attractant.

Glad I asked!

 

[Dan Thomas]

The "don't lube the shaft" thing in the manual might date from the pre-silicone lube days.

The Cessna seat rail/rollers/locks AD prohibits the use of lubricants on the rollers. In spite of that, I have found rollers seized because people insisted on oiling them. Seized rollers get flat-spotted. They eat the tracks, thinning the flanges so they might fail, and they cause the seat to tip due to the friction as the pilot tries to shift it, and the tilt drags the roller housing tangs on the underside of the aluminum rail flange and thins it from that side, too. Never lube those rollers.

But Cessna manuals mention using paraffin wax on the underside and edges of the rail flanges. That doesn't attract dust, and it inhibits galling and wear of the flange and lets the seat slide easily.

 

[murphey]

I use a silicon-based lube for bicycle chains and such for the yoke shaft. I also use it for the rollers on the seats (Cherokee PA28). Clean the rollers and the rails really good. Add the TriFlow, remove the excess. Works like a charm.

Tri-Flow TF0021060

 

[Domenick]

Never use grease. It attracts dust and forms sticky sludge that could cause control problems.

I always cleaned that shaft off with non-chlorinated brake cleaner. Sometimes I had to work it into the bushing in the panel and loosen up the crud in there and blow it out. The crud comes from skin oils from pilots' hands. I used dry silicone spray lube. Sprays on wet, then dries. Slick, and no dust attractant.

Exactly what I do. I have a dedicated, clean shoprag in a side pocket. Before every flight I stroke down both yoke shafts. Occasionally, I'll use brake cleaner and then a dry silicone as above. Replace the shoprag every year.

Some brake cleaner will remove paint and melt plastic. When I got my Warrior (PA-28-161) the yoke shaft panel bushing was gunked up. I packed the front and back of the panel with rags and sprayed brake cleaner into the bushing, worked the shaft and repeated. It took a few applications to get all the old grease and gunk, probably WD-40, out. You could also remove the plastic strip covering the bushing block, loosen the block to provide better access to the bushing. You'll not be able to remove the bushing, the block, or the plastic strip so during the procedure they simply hang off the shaft.

Of course removing the bushing block is an A&P-required action.

MX manual: https://www.dropbox.com/s/ejbeiwm3csvlue3/MM761895.pdf?dl=1
Part manual: https://www.dropbox.com/s/4rwf980pu6bmzut/pc761894.pdf?dl=1

If these do not cover your serial number try these:
https://www.dropbox.com/s/a3gpkpirg...-140,150,160,180,235,R180,R200.v2008.pdf?dl=1
https://www.dropbox.com/s/2ak082bs4...-140,150,160,180,235,R180,R200.v2009.pdf?dl=1

 

[Dan Thomas]

Some brake cleaner will remove paint and melt plastic. When I got my Warrior (PA-28-161) the yoke shaft panel bushing was gunked up. I packed the front and back of the panel with rags and sprayed brake cleaner into the bushing, worked the shaft and repeated. It took a few applications to get all the old grease and gunk, probably WD-40, out.

Brake cleaner will eat polycarbonate (Lexan). Keep it away from safety glasses and modern light lenses.

There's usually a bit of room between the shaft and bushing, so I have used a strip of 220-grit waterproof sandpaper, maybe an inch wide, hold it curved over the shaft to form a file, and work that around and back and forth to really scrub that crud out of the bushing. DON'T sand the shaft.

 

[Llewtrah381]

On my Warrior I’ve tried the dry silicone and it does OK - but never for as long or as well as a TINY dab of the Dow DC4 I have for the oil filter o rings. I put a bit on, work the yokes a lot, wipe it off, repeat, and after the last time I do this (which helps clean out the bushing), I put a tiny amount on and work it in. If I put on too much, I wipe off the excess. That usually lasts me a good while and hasn’t been messy if used sparingly.

 

[Tooltime70]

Best trick I’ve use so far has been no lube…gums up with in days! Piper recommends soapy water and microfiber dry cloths. I place a post it note on a 45 right on the yoke shaft holding it tight to the shaft and rotating and pushing it into the bushing. This acts like a cleaning cloth in the barrel of a gun. Gunk gets on the paper and you just keep using post it’s until no more gunk is left. I do this once every 2 months or when it gets kinda jumpy on the controls. It feels like a shaker stick when I pull back to flare….. NO LUBE….hats the root of the cause, it attracts dust and turns to sludge. Give it a try. It’s cheap as well. Micro fiber shoe polish the crap outta that shaft when done! Blue skies

 

[Gary Ward]

When I get my plane (PA28R) back from annual each year the shaft connecting the yoke is always well greased with virtually no friction giving the controls a nice, new frictionless feel. Now I'd kind of like do that maintenance myself periodically b/c after 150h it's not as nice...

Curious is there a specific lubricant I should use for that - or can I use whatever?

For clarification, this is what I'm talking about:
View attachment 113936

I don't know what piper suggest you use.
I have watched my buddy with a cheerokee and now a arrow use a little WD40 on a cloth.
He uses it pretty often before he fly's.

 

[AvNavCom]

Clear with a microfiber cloth. Dry silicone spray about every 6 months. *chef's kiss*

 

[Domenick]

I don't know what piper suggest you use.
I have watched my buddy with a cheerokee and now a arrow use a little WD40 on a cloth.
He uses it pretty often before he fly's.

I beg to differ.
Never use WD40 on anything you do not want gummed up as it eventually varnishes. WD40 is actually not a bad belly cleaner. The plane's not mine.
See post #8.

 

[Jim K]

My guy uses LPS 1. It's marketed as providing a "thin, greaseless, dust-resistant film". I assume it's a silicone type lubricant as recommended above, but they don't really just come out and say it. I will say that nothing collects on the shaft and it lasts almost a year. If it gets feeling stiff I'll give it a wipe with some sprayed on a rag.

 

[Jim K]

Lol,I just noticed this is from 2023. @ArrowFlyer86 , did you ever figure it out?

 

[AvNavCom]

My guy uses LPS 1. It's marketed as providing a "thin, greaseless, dust-resistant film". I assume it's a silicone type lubricant as recommended above, but they don't really just come out and say it. I will say that nothing collects on the shaft and it lasts almost a year. If it gets feeling stiff I'll give it a wipe with some sprayed on a rag.

I use LPS-1 on everything that moves but doesn't explicitly call for a grease. Hinges especially (including door hinges, which gets missed a lot, I think) as well as control cable rollers. My mechanic did it the first annual after I bought my plane and it became obvious that nothing had been lubricated in a very long time. Was absolutely night-and-day in terms of smoothness of operating the flight controls and trim handle.

 

[Dan Thomas]

My guy uses LPS 1. It's marketed as providing a "thin, greaseless, dust-resistant film". I assume it's a silicone type lubricant as recommended above, but they don't really just come out and say it. I will say that nothing collects on the shaft and it lasts almost a year. If it gets feeling stiff I'll give it a wipe with some sprayed on a rag.

LPS-1 isn't silicone. It's mostly kerosene, and kerosene is more of an oil than a solvent. It will attract dust and form a sludge in the bearing. Stuff does not tend to collect on the shaft, but it sure does in that bearing, and I have removed a lot of sludge from those.



Piper forbids lubricating that shaft for good reasons. But their advice was given before the days of dry silicone spray, which dries and does not attract dust and lubricates very well and doesn't sludge up the bearing.

One of the more dangerous things around an airplane is a pilot with an oil can or a can of LPS. I have found flap rollers seized solid due to being oiled and getting sludged up and water and dust mix with the oil. Not to mention terrific staining of the whole area. Found seat rollers seized solid due to oiling. Very often found flap actuators fouled by copious amounts of lube, and often the wrong lube altogether. Lube that gets into the travel limit microswitches and fouls their contacts so that the flaps won't work, or worse, won't retract in a go-around. Found starter drive Bendixes that hang up and won't engage (on Lycomings) because the owner or mechanic spritzed it with oil spray of some sort. The service manuals forbid that, and specify ONLY silicone spray. From the Prestolite Aircraft Starter manual:

 

[Dan Thomas]

I use LPS-1 on everything that moves but doesn't explicitly call for a grease. Hinges especially (including door hinges, which gets missed a lot, I think) as well as control cable rollers. My mechanic did it the first annual after I bought my plane and it became obvious that nothing had been lubricated in a very long time. Was absolutely night-and-day in terms of smoothness of operating the flight controls and trim handle.

Cessna calls for dry graphite on piano-type aileron hinges. Oil in there attracts dust that grinds away the aluminum pin against the aluminum hinge halves. You'd be better off with no lube at all.

But getting the graphite in there is difficult. I used a small syringe, put a bit of graphite in it, then some non-chlorinated brake cleaner, shook it up good, then dripped the stuff on the aileron hinges. The brake cleaner carries the graphite into the hing and then dries almost instantly, leaving no oils to mix with dust and water.

Remember, as I pointed out above, that LPS-1 is nothing but kerosene. It is NOT a quality lubricant and will not last. And the end result is stuff that's worn out before its time.

From a Cessna manual:



Most areas that call for an oil are to be lubed with a MIL-spec 7870A (or later) general-purpose oil. This stuff lasts and hangs on for a long time. Royco 363 is an example of that oil. Using LPS to loosed stiff control system pulleys won't last long; the kerosene dries up and the old, hard grease goes back to seizing the pulley. The specified MIL-7870 oil will soften the grease and keep it that way for a long time.

 

[AvNavCom]

Remember, as I pointed out above, that LPS-1 is nothing but kerosene. It is NOT a quality lubricant and will not last. And the end result is stuff that's worn out before its time.

Darn it! And here I was congratulating myself on being a conscientious aircraft owner. Thanks for the great information. Checking my 1966 Cherokee C service manual, it indeed calls for MIL-7870. Interestingly, it specifies that oil for the control surface hinges too. I will correct the error of my ways! Based on your advice above, I may look into the dry graphite option too.

 

[AvNavCom]

Remember, as I pointed out above, that LPS-1 is nothing but kerosene. It is NOT a quality lubricant and will not last. And the end result is stuff that's worn out before its time.

Actually, I'm an idiot. I just checked and it is LPS-2 that I have been using, not LPS-1. Still not the recommended lubricant, but perhaps slightly less egregious than LPS-1.

 

[Dan Thomas]

Actually, I'm an idiot. I just checked and it is LPS-2 that I have been using, not LPS-1. Still not the recommended lubricant, but perhaps slightly less egregious than LPS-1.

From the LPS-2 MSDS:



It does have some oil in it, but I have seen a lot of LPS-2 all gummed up around hinges and so on. Most guys are using the aerosol version, and when sprayed, it gets on everything in the vicinity and makes a mess. It's the stuff mechanics often use on Cessna flap actuators, and they wreck the microswitches doing it.

It does have a MIL spec:

• MIL-PRF-16173E Grade 3 Class 1 (except 3.5, 3.6)

I applied the MIL-7870 oil using small syringes. I stuck one of those narrow tubes you get with WD-40 and the like into the end of the syringe, letting me deposit just one or two drops exactly where it needs to go, minimizing the mess and sludging up. The rubber seal on the syringe's piston will eventually swell up and stick in the bore, but those syringes are cheap so you grab another.

 

[Gary Ward]

This thread has got me to thinking of why my 172 doesn’t seem to need lube on the control wheel shaft?

 

[Dan Thomas]

This thread has got me to thinking of why my 172 doesn’t seem to need lube on the control wheel shaft?

Because you don't lube it and you don't grab the shaft with your hand. Your skin will leave oils on the shaft. Some pilots will hold the elevator full-up during runup, to keep the thrust from pulling the prop closer to the ground where it picks up debris, and they will sometimes grab the shaft to help hold it back.

The shaft bearings in these airplanes are usually phenolic (an old linen-reinforced urea-formaldehyde material dating back to WW2; you see it when you look at those brown control cable pulleys) or nylon. Both materials are considered self-lubricating. If they're never lubed, they will continue to slide easily, but once you oil them, you will have ongoing stickiness developing. If you take the control lock out, then go move the elevator up and down by its trailing edge, it should move easily without any shudder being felt. Shudder means sludge making that shaft sticky, and it's inside that bearing. It also make the elevator a bit sticky in the flare, making precise pitch adjustments harder. Your landings can get rougher.

 

[Gary Ward]

Because you don't lube it and you don't grab the shaft with your hand. Your skin will leave oils on the shaft. Some pilots will hold the elevator full-up during runup, to keep the thrust from pulling the prop closer to the ground where it picks up debris, and they will sometimes grab the shaft to help hold it back.

The shaft bearings in these airplanes are usually phenolic (an old linen-reinforced urea-formaldehyde material dating back to WW2; you see it when you look at those brown control cable pulleys) or nylon. Both materials are considered self-lubricating. If they're never lubed, they will continue to slide easily, but once you oil them, you will have ongoing stickiness developing. If you take the control lock out, then go move the elevator up and down by its trailing edge, it should move easily without any shudder being felt. Shudder means sludge making that shaft sticky, and it's inside that bearing. It also make the elevator a bit sticky in the flare, making precise pitch adjustments harder. Your landings can get rougher.

Thanks for the explanation.
I just landed, 1.9 hrs, 13 mostly one wheel t&g,without flaps unless I want to land short.Like a fallen leaf onto the runway at 60kts at idle with no flaps.Night current.Fun flying for me.
I looked tonight at my shafts and they appear to be anodized black with no wear marks that I could see. Yeah you’re right I don’t think I ever touch those shafts? Aircraft only has 2600 hours so far. I fly a lot and many landings. She is smooth as silk.
Piper shafts are larger and appear bare? Seems they would need more lubricant and are exposed to more dust and dirt.

 

[Dan Thomas]

Piper shafts are larger and appear bare? Seems they would need more lubricant and are exposed to more dust and dirt.

Chrome plated. The bearing in the panel will also be nylon or phenolic and will require no lube.

 

[WDD]

The Cessna Pilots Association maintenance workshop Cessna guru uses this on anything that is supposed to move.

Amazon.com: Tri-Flow Lubricant : Tools & Home Improvement

Buy Tri-Flow Lubricant: Lubricants - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

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[Dan Thomas]

The Cessna Pilots Association maintenance workshop Cessna guru uses this on anything that is supposed to move.

View attachment 148905

Amazon.com: Tri-Flow Lubricant : Tools & Home Improvement

Buy Tri-Flow Lubricant: Lubricants - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

Even the gurus are sometimes mistaken. This is the MSDS list of contents for that lube:



It's mostly oil and solvents. The solvents evaporate and leave the oil behind. Paraffinic oils have paraffin in them and leave a waxy sludge behind, which is why, for example, Cessna specifies #10 non-detergent oil for the flap actuator jackscrew. If one uses ANYTHING other than the specified oil, you can get paraffin or other sludging compounds in the recirculating-ball tube in the mechanism, which stops the balls from moving and rolling between the screw and nut, and you get severe wear so that you have to then start replacing expensive parts. Cessna knew that when they wrote the manual. Mechanics who have a high opinion of their "knowledge" will often take a different path that can cost their customers a lot of money.

There are no lubes better than what Cessna specifies for their airplanes. I know this from experience. Once I started using the stuff specified in the service manuals, and you have to watch the aircraft serial numbers for the right stuff for the flaps, for example, I had no problems with stuff seizing up or going dry. No sticky or chattering control columns. No black gunk on the airplane near the control surface hinges or flap rollers. And even better, the right stuff actually cost less than the aerosol cans of LPS or whatever. Aerosol cans deposit about 100 times as much lube as needed, making a mess and spending money faster.

 

[Larry Korona]

From the LPS-2 MSDS:

View attachment 148629

It does have some oil in it, but I have seen a lot of LPS-2 all gummed up around hinges and so on. Most guys are using the aerosol version, and when sprayed, it gets on everything in the vicinity and makes a mess. It's the stuff mechanics often use on Cessna flap actuators, and they wreck the microswitches doing it.

It does have a MIL spec:

• MIL-PRF-16173E Grade 3 Class 1 (except 3.5, 3.6)

I applied the MIL-7870 oil using small syringes. I stuck one of those narrow tubes you get with WD-40 and the like into the end of the syringe, letting me deposit just one or two drops exactly where it needs to go, minimizing the mess and sludging up. The rubber seal on the syringe's piston will eventually swell up and stick in the bore, but those syringes are cheap so you grab another.

So what brand is MIL-7870 oil, and where do you buy it from? Same question for the graphite power.

 

[Dan Thomas]

So what brand is MIL-7870 oil, and where do you buy it from? Same question for the graphite power.

Several companies make it. We used to buy it as Royco 363, from Aviall. After I retired, Boeing bought Aviall, and on their site I find those two lubes shown:



You would have to set up an account with them to get prices. A quart of 363 will last you a lifetime of airplanes. Check the rest of the site, too, and maybe find some deals. We used to buy Condor tires from Aviall (made by Michelin) at very good prices. https://shop.boeing.com/distribution#UkRfQkRJ

 

[Larry Korona]

Several companies make it. We used to buy it as Royco 363, from Aviall. After I retired, Boeing bought Aviall, and on their sire I find those two lubes shown:

View attachment 148923

You would have to set up an account with them to get prices. A quart of 363 will last you a lifetime of airplanes. Check the rest of the site, too, and maybe find some deals. We used to buy Condor tires from Aviall (made by Michelin) at very good prices. https://shop.boeing.com/distribution#UkRfQkRJ

Thanks for sharing this information!

 

[M20K]

The Cessna Pilots Association maintenance workshop Cessna guru uses this on anything that is supposed to move.

Mooney used to recommend it too. But there are downsides of grit get collected in it if used improperly. Not anywhere in the same league as to how bad WD-40 is, but basically similar issues.

 

[Lama1125]

As an IA, I always tell people to never lube the control shafts. Use alcohol to clean and just keep it clean. Never had a single issue in 10 years of doing this. Lubricants make it worse and some eat the block away. Make it clean and keep it clean. All you will ever need and all I do on my personal plane.

 

[Dan Thomas]

As an IA, I always tell people to never lube the control shafts. Use alcohol to clean and just keep it clean. Never had a single issue in 10 years of doing this. Lubricants make it worse and some eat the block away. Make it clean and keep it clean. All you will ever need and all I do on my personal plane.

That works, too. The guide block ("bearing," as some call it) for that shaft is usually made of Micarta or nylon or Delrin or some similar material that is considered self-lubricating. Those materials are commonly used for fairleads and rub strips for control cables, and they are never lubricated. Or, they shouldn't be lubricated. That's a good way to wear out a cable, with oil catching dust and grit that eat away at the cable.

But almost any airplane will have sludge in that block from people lubing the shaft. If that crud is not cleaned out, the shaft's movement will be rough or sticky.

 

[texasclouds]

 

[sourdough44]

I re-lube every 2-3 months. Jokes aside, I like a lubed control shaft. LPS of some flavor, I don’t fly in a dust storm.

 

[WDD]

I also don't live in or fly in a dusty environment. I would think a thin coating left over from regular cleaning/re "spritzing" from a light lubricant would ward off corrosion. That would outweigh the danger of sludge forming. I'm thinking primarily of aileron and elevator hinges, door hinges, etc.

 

[Racerx]

I had problems with the tru trak and pitch oscillation. This after it had been rock solid. They recommended lubing the shaft and after some sry silicone spray it's back to being solid.