I'm curious how long a set of roller bearings will last in static applications. I heard from another source that AT&SF 2926 needs new ones. Would this be from rust damage, worn out when placed in the park, developed flat spots from sitting in one position for too long? I seem to recall that 765 ran on her original bearings after being restored, what about 611 or 614 or other roller bearing equipped engines..how many are still with their original bearings? Speaking of roller bearings, do rod bearings wear out faster than main axle bearings?

Shelf life means on the stock room shelf. In this case forever as long as they don't get rusty for some reason. Installed could last as long as water is kept out and the lube is kept fresh.

I have heard stories of roller bearings flattening from sitting but have never heard of any cases in actuality.

Battleship main turrets rest on rollers within a race. That is a lot of weight. I wonder if they found flat spots after long periods in the mothball fleet.

The 3751 has roller bearings on all axles. They were found with oil still in the cellars and no supposed flat spot from sitting for 30 years. The engine is still running on these roller bearings.

I do not believe that roller bearing steel will creep over time. Maybe Mythbusters should test that myth! Now that would be a boring episode, until the last scene where Adam and Jamie use C4 to blow the bearing to smithereens.

It was my understanding that the bearings on the 2926 are in good condition. Axle boxes were checked prior to removal from park...no water, only good oil. I do know that all of the rod bearings on the 2912 in colorado need to be heavily rebuilt or replaced. Two Santa Fe northerns, maybe the stories have been transposed?


Jason

from trainorders.com

As I said in a previous post they asked us for a donation of the bearings
and we're not quite that charitable considering that the total was something
like $90,000. Wish them the best and hope they don't need a total replacement.

The idea that the rollers or races would somehow deform while sitting strikes me as impossible, considering that these things withstand big impact loads without brinnelling while operating.

The shelf life of the lubricant is another matter. I wonder if there is a limit to how long we should rely on the lubrication in no-field-lube rotating-end-cap bearings on spare wheelsets that may be stored for years before use. The outer housings of these can be rotated every few months to spread grease over the steel surfaces inside, to prevent corrosion. But how long does the lubricant last?

Aarne Frobom
Slid Flats, Michigan

The 611 is moved, several feet, from time to time, just to keep the bearings in top shape, and when you see it at VMT, you can see the lubricant dripping from it's rod bearings.

It also must help them, they pull it, and the 1218 out, from time to time, for photo shoots, and special events with NS.

I believe Santa Fe regularly pulled 2925 and 5021 in and out of the Belen roundhouse to keep the bearings from "setting". I did see in that Strasburg posting that water or other contaminants had gotten into the bearing races of roller bearings, and that they needed replacement. Also, did 765 not just have her main driver roller bearings replaced?

Amtrak spotted three 91XX series NYC baggage cars at Lancaster, PA, around 1977 or 1978. They asked us to inspect them prior to movement in March 2005. The grease was clean, clear yellow and the bearings and races were bright. They rolled along fine without symptom.

In other words, it all depends ...

Insert rolling eyes smilie here...

Trainorders.com, a reliable news source.

Please fill us in Clem, what bearings on 2926 need replacing, and where did the $90,000 figure come from? I know you know the truth, your picture is right on the website.

Like most organizations that are restoring historic railroad equipment, we do not discuss the daily in and outs of the restoration effort on line. The only official source for information can be found at http://nmslrhs.org/ Until a bearing problem shows up on their website, I wouldn't worry about it...

The comment on trainorders struck me as funny, as I didn't think the restoration had progressed to the running gear yet. With the pit recently completed, I guess it is now possible to get a good look at it from top to bottom. Is it possible to look at the condition of the main bearings without removing the axles from the frame?

standard inspection method on the mains without disassembly is to do a particle count on the oil from the cellar providing that it has not been flushed and re filled. Next would be to put a bore scope through the filler holes so that the rollers and races could have a visual. However without disassembly taking measurements with inspection equipment is not possible.