Kubota "Dry" Bushings?

[XYooper906]

I am in the process of freshening my recently acquired G5200H lawn tractor. I ordered and received some replacement bushings for the steering sector gear and steering shaft. They are P/N's
66021-41120 and 66021-41130 respectively. The Kubota online parts list merely lists them as "bearings", but the vendor I ordered them from lists them as "Metal, Dry". I assumed that they were going to be some sort of Oilite bushing, but when I received them they appear to be a bronze bushing with a perforated plastic inner coating.

Is this a Teflon type of coating that is meant to be used without any type of lubrication, as the "dry" nomenclature suggests? I have been unable to find any information to suggest whether any lubrication is recommended. My instincts tell me to lube them, regardless, but I don't want to use anything that would degrade the coating.

 

[TheOldHokie]

I am in the process of freshening my recently acquired G5200H lawn tractor. I ordered and received some replacement bushings for the steering sector gear and steering shaft. They are P/N's
66021-41120 and 66021-41130 respectively. The Kubota online parts list merely lists them as "bearings", but the vendor I ordered them from lists them as "Metal, Dry". I assumed that they were going to be some sort of Oilite bushing, but when I received them they appear to be a bronze bushing with a perforated plastic inner coating.

Is this a Teflon type of coating that is meant to be used without any type of lubrication, as the "dry" nomenclature suggests? I have been unable to find any information to suggest whether any lubrication is recommended. My instincts tell me to lube them, regardless, but I don't want to use anything that would degrade the coating.

PTFE, Rulon, and Frelon are commonly used linings in dry running metal sleeve bearings. They do not need and will not benefit from lubricants.

Dan

 

[North Idaho Wolfman]

Your instincts are wrong in this case.
Yes the inner lining is PTFE (aka teflon), use no lube.

 

[XYooper906]

Thank you for your replies. I will install them without lube.

 

[GreensvilleJay]

You may want to spray the steering shaft and nearby 'stuff' WITH a coat of 'rustcheck' type lube, just to keep the RUST from forming.

 

[XYooper906]

You may want to spray the steering shaft and nearby 'stuff' WITH a coat of 'rustcheck' type lube, just to keep the RUST from forming.

I have had success with Fluid Film for similar applications in the past. It is safe on plastics, but not on non-oil-resistant types of rubber.

I may test the old bushings (if there's any antifriction coating left) after I remove them by soaking them with Fluid Film. My concern with any lubricant would be if it caused swelling or deterioration of the coating.

 

[hagrid]

You may want to spray the steering shaft and nearby 'stuff' WITH a coat of 'rustcheck' type lube, just to keep the RUST from forming.

WD-40?

 

[TheOldHokie]

I have had success with Fluid Film for similar applications in the past. It is safe on plastics, but not on non-oil-resistant types of rubber.

I may test the old bushings (if there's any antifriction coating left) after I remove them by soaking them with Fluid Film. My concern with any lubricant would be if it caused swelling or deterioration of the coating.

Of course that assumes the lining in the old bushings is the same as the new. Let me suggest you just go with the flow and forget about sprays. If you are dead set on sprays you have little to worry about. The lining is likely some PTFE based compound and chemically resistant to just about everything.

Dan

 

[XYooper906]

You may want to spray the steering shaft and nearby 'stuff' WITH a coat of 'rustcheck' type lube, just to keep the RUST from forming.

Your insight was right. There was rust on the pivot shaft for the steering gear sector. The old bushings were worn significantly, but I believe that besides the extra play in the steering that this causes, the steering was still a bit tight to turn. I believe that the rust was contributing to the stiff steering, as well as accelerating the wear of the plastic lining.

I de-rusted the shaft by immersing it in my electrolysis bucket overnight. There was light pitting afterward, but not too much wear on the shaft itself. I polished the shaft with my buffer wheel to give it as smooth a finish as possible. With the new bushings installed in the steering sector, it was very smooth and side play was VERY minimal.

I can see both sides of the discussion re: spray or no spray. I think if the equipment is getting used regularly, rust inside a joint like that is unlikely to be an issue. But this tractor has only seen 400+ hours of use in 37 years, so I think it sat a lot between uses. He probably washed it after each use judging by the condition of it. So moisture in that joint was likely to be present.

Additionally, the upper steering shaft has a rubber bushing. I noticed that there was some squeaking coming from that point when steering, so I gave it a light coating of silicone grease to prevent that. Hopefully, the combination of everything will make it a SMOOVE operator again.

Thanks for the comments everyone, much appreciated!

 

[GreensvilleJay]

After what you did , it'll last another 37 years !!!

 

[fried1765]

WD-40?

WD-40 = worthless!

 

[hagrid]

 

[cthomas]

The WD-40 cans I come across are soon setup as target's for the 9mm. That is how much I think of WD-40.

 

[GeoHorn]

I use WD40 by the gallon cans. Several full ones are sitting in my place because I buy them whenever they’re on-sale. I use it instead of soap in the wash-water-bucket to keep from having to polish this thing (which was last polished in 1997)…WD40 works great: