Thoughts on Lube Free Bushings in Spindle Axle Holes??

[oliver2-44 9,929]

I'm posting this here to hopefully get a broader viewing.  So on my Suburban projects I need to bush at least one of the 2 cast iron front axles 3/4"spindle holes.  I've read where several have used bronze bearings, bunting bearings, oilies bearings, etc.

At the dams we were moving to using a lot of lube free bearing for environmental purposes, thereby reducing the places where oil or grease can get in water.  However in a lot of these installations we went with stainless steel shafts.  But in a few there were carbon steel shafts. I've worked with a couple of grades of Delrin (plastic) that has a good weight load rating, and some other plastic polymer type stuff.  Interestingly there are a lot of these material available as bearings on Ebay and Amazon.

 

The nice thing about going with a lube free polymer bearing is no grease.  So what are ya'll thoughts about using polymer bearing in an axle with carbon steel spindles?   

 

if you used Bronze would you use a 7/8" OD or 1" OD and then a 3/4" ID

[8ntruck 7,183]

If I were doing this job, I would use bronze bushings, but still grease them.  

 

To go the no lube option, oilite bushings would be a possibility.  But, given the dusty, dirty environment, I'm not sure how long a set up like this would last.

 

Might be possible to bore the axle to accept some 'lubed for life' sealed needle or ball bearings.  Got to remember that 'lubed for life' is a self fulfilling prophicey - when the lube runs out, the life is over.

 

Good luck.

Edited September 21, 2021 by 8ntruck

[ri702bill 8,564]

All:

I've added bushings and thrust washers to two cambered axles recently. I flycut the lower splindle boss in the same setup as drilling and reaming - this is to give room for the thrust washer and allow me to machine out the vertical play. I do the same with the pivot boss - the back boss gets chewed up so I machine about .020 off to clean it and leave room for a .030 washer.

[kpinnc 12,808]

If I had to run oilite or delrin, I'd run full length bushings. One for each wheel, all the way through.

 

Old axles tend to have a little wear, so adding non-lube bearings of the same size as original is asking for trouble.

[Skipper 1,789]

I would not go grease free on the front spindles. As to what size bushing, you always aim to remove least possible of your front axle.

 

Saw some sleeves the other day at motion industry. Very thin. meant to put on a shaft where the oil seal surface was damaged. If they have enough material to get things back to round, that might be the most gentle way.

 

I too like the idea of a a couple NRB's in the spindles, and an oilseal on top. Not sure they can take the load though.

[Lee1977 6,874]

I don't know what type of polymer bushings your mention. Every where I have seen plastic bushings used they wear the shaft faster then bronze.

[ri702bill 8,564]

All:

I agree with Lee that the plastic can be abrasive on mild steel. I definetly would NOT use the split "Nyliner" bushings in the axle pivot bore - if the bore is not consistant on size and roundness the bearing will walk out, kind of like squeezing a tube of toothpaste. I use the better grade bronze with the iron content bushings for the pivot bore, not the Oilite. No problem boring the pivot hole in the axle - there is plenty of meat.

I did find that I had to switch the axle on the C81 - one original spindle bore was not concentric to the casting - looked great on the top but way off on the underside.

I also use the 1/8" thick bronze thrust washers with the iron content under the axle - would not trust a flanged Nyliner to stand up there. ( also had to clean up the top of one steering arm - it is bent flat stock and was welded at a slight angle ...). There is a local company in Rhode Island called IGUS - they have many different types of plastic they use for their bearings, but pricey.

Bill

Edited September 22, 2021 by ri702bill

[71_Bronco 1,072]

Not sure what the original stock wheels had for "bushings" on my '62 Lawn Ranger (can check tonight).

 

Regardless, the non-bearing wheels did a number on the shafts of my spindles (see pic below).

 

Though, I'm sure things have changed / been improved over the last 60 years since this tractor was built lol

 

Side note, I have seen the "oil-lite bronze" bushings used at my old job (CNC machine shop). In most cases, I believe the parts sliding inside the bearings were hardened steel, not plain carbon steel. Not sure if that would make a difference.

 

[71_Bronco 1,072]

4 hours ago, ri702bill said:

SNIP

There is a local company in Rhode Island called IGUS - they have many different types of plastic they use for their bearings, but pricey.

SNIP

 

I use to use one of their plastic sleeves in one of the products made at my previous job. Was used as a liner between a cast aluminum part and a polished shaft. As you said, they were pricey.

 

The other issue with them was tollerance stack-up. Since they are soft, the ID will shrink if the bore they are pressed into is under-sized, causing the polished shaft to bind. We had to be very careful with the tolerances of our parts.

[Handy Don 12,663]

I've been around some engineering teams that spec'd some of the "exotic" plastics for high-load, low speed bearing situations similar to front axle spindles. Lab testing led them to be expecting at least a 10-year life under adverse conditions (moisture, dust, extreme cold/heat like -40º to +120º F, and shock) but much longer otherwise. The zero maintenance aspect was a key factor as were tolerances that permitted a few thousandths of lateral displacement by the shaft, due to the plastic's compression, without harming the usability of the product.

Edited September 23, 2021 by Handy Don

[peter lena 8,878]

@oliver2-44 https://lucasoil.com/products/grease/lucas-x-tra-heavy-duty-grease  for $ 5 , at walmart , are you serious about making your stuff last ?  polyurea rated , anti sling rated , and a 560 deg drop point , nothing that I have used this on has given me any problems, like whining mower deck bearings , pto drive bearings , all my chassis fittings and my linkage ends . just my own experience , do what ever you like , pete