The B21 Rolls Again

It took nearly three weeks but we finally completed the repairs to the B21 tractor.  We had to remove the front axle and disassemble the left side bearing box to get at the bearing that had failed.  In the process we discovered that at some point in the tractor's past someone had replaced this particular bearing before.  We could tell this from the grind marks on the inside of the bearing housing.  Evidently during this earlier event the technician had difficulty removing the bearing from the housing and resorted to grinding it out.  We found this repair history a little curious for two reasons.  First was the fact that the bearing had failed before.  Now bearings do wear out with time but this particular bearing is not the typical fail point - far more likely would be one of the main axle support bearings.  These, however, were fine.  The second thing that was funny was that the bearing had to be ground out - they should just slide out from the recess in the housing where they are located.  Indeed this time I had difficulty removing the old bearing.  I didn't grind it out, but I had to build a special pry tool in order to pull it out of its recess.  Once the old bearing was out we realized that the new bearing would not fit nicely into the recess.  At this point we decided to go ahead and replace the entire housing.  Perhaps the bearing failure in the past had distorted the housing or perhaps the housing was never quite in spec and the bearing had never seated properly.  In any event it was for us more delay as we ordered the part.  When it finally arrived we went ahead and assembled the bearing box and the rest of the front axle.  Everything went together well and I am confident that this particular bearing will last a very long time.  While we were at it we replaced the front tires.  The previous owner of the tractor had for some inexplicable reason put on front tires that were too large in diameter.  The result of this was that when the tractor was in four wheel drive mode (which it is 95% of the time) the front and back tires rotated at slightly different speeds which tended to tear up our new roads a bit.  On the day after Thanksgiving we finally had everything back together and the tractor rolled again.