Are self lubricating bronze bushing 100% maintenance free?

[Karlsenkystfiske]

I have some cheap plastic line pulleys on board with what is supposed to be self lubricating bushings that the wheel run off. The guy who sold them to me claims that I do not need to do any maintenance. I find that kind of hard to believe. Wouldnt they live longer if one cleaned and oiled them every once in a while?

 

[justanothersailboat]

There's a kind of bronze product which is made from little granules so it's full of tiny holes, then filled with oil. That is in theory lubricated-for-life. It certainly lasts well. So it could be that stuff? it still lasts better if kept clean, further oiling won't hurt it... However I don't seem to see it on boat things. I would not have expected to find it on a fairly basic plastic accessory.

 

[lustyd]

Looking at that plastic I'd say UV will kill them before they need lube so wouldn't worry about it too much. They might run slightly smoother, but if you want frictionless you'd probably have some real bearings in there. At most I'd consider a squirt of silicon/ptfe spray now and then

 

[KevinV]

Certainly don't use oil - you've a good chance it will swell the plastic and cause it to stick. Plastic running on bronze will have little friction - I'd just wash it out with fresh water every now and then.

The benefit of dry things is that dust has nothing to stick to, so it can't build up and cause wear.

 

[colhel]

There's a kind of bronze product which is made from little granules so it's full of tiny holes, then filled with oil. That is in theory lubricated-for-life. It certainly lasts well. So it could be that stuff? it still lasts better if kept clean, further oiling won't hurt it... However I don't seem to see it on boat things. I would not have expected to find it on a fairly basic plastic accessory.

It's called oilite.

 

[justanothersailboat]

Thanks colhel. I'd forgotten.

KevinV - good point, I was only thinking of the bronze stuff, not the plastic.

Clean is good though. The plastic won't wear the bronze (or possible oilite) but grit embedded in it probably would.

 

[rotrax]

First Mate had a gearbox siezure at Donnington Park with her racing sidecar due to a sintered Olite bush extruding and popping a sealing plug out of the gearbox. This allowed the oil out.

The cause was repeated clutch starts which put high downward pressure as the mainshaft and layshaft tried to separate under the load. The Olite bush extruded and pushed out the plug which was just like a small cylinder block core plug.

A solid bush fixed it permanently.

 

[justanothersailboat]

Interesting, Rotrax... I remember having to machine the stuff a few times and finding it startlingly compressible. IF it were used in plastic that would probably not be a problem. But it's just as possible the pulley doesn't use it and just relies on a waxy/low lubrication plastic and the saleschap was being optimistic.