I woud guess that the bearing color isn't a problem Most engines have some baked on lube and it is usually orange to brown. Feel it with your finger, If it is rust, it will feel rough, If it is backed on oil, it will feel smooth.

If the tank isn't a new one, I would check the clunk line in the tank. I've been bit more than once with one that had a crack in it and was sucking some air after a quarter tank was used.

If you don't have the adjustment limiters removed,now is the time.We've had a couple guys with these engines at the field that couldn't get them to really peak out or idle correctly, but once we removed the limiters, they tuned just like any other engine.

Last, you may wan't to soak the carb in a jar of fuel ovenight then removeboth needlevalves and blow through the plumbing to make sureall the goo from storage is flushedout. Itake the high speedneedle out and blowinto the vent line. You should get a nice steady stream of fuel with little pressure on the vent.If it is blowing air and spittingfuel, your tank is empty or the clunk line is broke. We had one of those yesterday.After blowing through the high speed, the remvoe the idle mixneedle and blow through again. This should dislodge any crud in the spraybararea.

Last are you using a new Glow Plug? Old plughs may haveenough crud on them to keep them from doing the job, even though they glow red.

Don