I have noticed that the vibration damper on my B-59 vibrates from side to side. I spoke with a mechanic who works on this engine for a living. He told me the thrust bearing on the crankshaft main is not made very well for the stress that this engine can take. He said he had to replace many of them. If you place a dial indicator on the damper and pry in and out on the crank you should only see up to a max of . 017 movement. He has found as much as . 250 and more. You would not know it by the way the engine runs until you check it. I am hoping its only a bad damper and not the main thrust bearing. I have not got under there to check it yet. Has anyone else come across this problem before?