Combines shaker shoe grief

Check that shoe is running straight forward and back and not diagonal by measuring distantce from main frame to point on shaker at say start of stroke or end_ middle what ever check at all three points make sure same both sides. look for cracks. Even a beraring not seated properly in the eccentric can put it out of whack. Make sure the steel sheave that slips in to rubber and then over stub shaft seats properly in the box to. check rubbers and tighten new ones mid stroke. Usually most trouble free area on gleaner as was designed shorter because of the pre separation of acc_rollers and air blast which lightens the load for the shoe . Red ones you talk about have had trouble as any of them would mainly because of running crooked and then they have the alternating system of top sieve forward bottom back so really puts a strain on everything in the box ( cracked up sieves and broken box ) Seen very ugly results on red ones and very annoying to fix. If your looking at red ones check it out and if you see measurement marks painted on you'll know they've been on to it.But yeah red ones pretty simple reliable machines if you get a good one . Get a base mark for yours to and check it . Sounds to me like a allignment problem or worn rubbers pretty easy to fix . Sorry if you already know all this as it seems you had plenty of practice in the l2_3.

Tightening at the proper location in the stroke is very important. I always review the tightening sequence in the service manual to make sure I do it correctly.

If that is the 5_8" rod that goes accross the front be sure the rubber is on it half way accross. It keeps the whip out of rod. Other thing is to get it tight. I pull for all I'm worth on end of wrench while holding the far side. Good luck