New bearings for the mower

Several months ago, while dismantling the "pivot group" of my New Holland 451 mower, I noticed that the bearings in this assembly were in pretty bad shape.
The old bearings after being removed and cleaned.  The dark portions on the surface of some of the rollers are not from grease.  Rather they are pitted areas darkened from corrosion.


A similar level of corrosion on a bearing cup or raceway.
To prolong the life of the mower and further justify my current restoration efforts, I determined that it would be necessary for me to replace these bearings.  Removing the old bearings was quite a learning process, but I eventually was able to accomplish this with careful preparation.  Prior to removal I would first chill the entire assembly in a freezer (after it was degreased and cleaned) and then remove the assembly from the freezer and apply heat to the metal on the outer portion of the bearing to be removed.  In this manner I was able to slightly reduce the outer diameter of the bearing shaft and simultaneously slightly increase the inner diameter of the bearing assemblies.  At this point I would then work quickly to coax the bearings off their shafts by tapping with a hammer. 
The three "connecting links" with their new bearing cups installed and a new coat of paint.  I found that the bearing cups went in more easily if I cooled the cups in a freezer and heated the connecting links in an oven prior to pounding with a mallet. 
After I had prepared the connecting links, I next installed the first set of dust covers and bearings on each shaft in the assembly.  In this case I chilled the shaft assembly in a freezer and warmed the bearings in an oven.  I have seen YouTube videos of people heating bearing assemblies to a very high temperature with a welding torch.  This is not a good idea as it would probably completely alter the special properties imparted on the bearings during manufacture. 
This photo shows the method I used to pound the bearings on the shaft.  I was able to find a scrap piece of metal electrical conduit that fit perfectly around the shaft and transferred the energy of the hammer evenly to the bearings.  Obviously I didn't use the stone countertop in our kitchen as a pounding surface.  The countertop is just more photogenic.
The ten sets of new bearings installed.  One more coat of paint and it will be ready. 

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