Originally Posted by OGR Webmaster:
...
RELIABILITY
This is a big one. In today's world of Class 1 railroading, a steam locomotive has to be reliable over the road. Steaming problems, hot bearings and any other issues that cause an engine to suffer road failures are a huge operating problem for the host railroad. Older locomotives with plain (non-roller) bearings on the axles can have problems today because suitable lubrication is tough to find. If the bearings have not been converted to oil and still use the old grease cakes, finding a suitable grease to use in those bearings today is tough.
A plain bearing locomotive converted to oil (such as the 4449) can be just as reliable as a roller bearing engine. But older, smaller power, perhaps owned by organizations without the resources to convert the old bearings to oil, simply can't handle the stresses of all-day running because the proper lube just isn't available any more.
These are but a few reasons why "...the US is in love with northerns and berkshires..."
Originally Posted by Hot Water:
Originally Posted by Dominic Mazoch:
I thought 4449 was buit in such a way so the driver bearings were constantly lubed. SP identified these with stars on the center of the wheel. Or was the type of lube used changed.
No, the "type of lube" was NOT changed. But what does this have to due with the title subject?
It sounds relevant to me because Rich was talking about the need for reliability in mainline service.
http://www.chaski.org/railfan/viewtopic.php?t=590
"... stars on the main axle hubs of SP 4440 denoted friction bearings ..."
"... stars on the SP axles that had friction bearings ..."
http://www.youtube.com/all_comments?gl=UG&hl=en-GB&v=uK5r3XKRBsc
I got my information about the stars from Doyle himself. I'll ask again but I'm pretty sure he's told me numerous times that everything [on 4449] is roller bearing EXCEPT the drivers which are friction bearings ...
... it's correct that the Friends [of 4449] have installed roller bearings on all but the drivers. however, historically, the stars indicated the spring pad lubricators had been installed on friction bearings.
It's too bad the 4449 wasn't a later GS-5 or GS-6 model which was originally built with roller bearings throughout. Some years ago they had to go to a lot of trouble to upgrade the 4449 with roller bearings on all axles to make it acceptable for modern mainline service. [edit: I'm not sure that the main drivers were actually converted to roller bearings, as was talked about?]
N&W, the last holdout of mainline steam power, developed advanced automatic lubricator systems for their steam locos to reduce/streamline maintenance and improve reliability. So the later model steam locos with these kinds of improvements would be better candidates for modern mainline steam excursion service.