Need some help on this Legacy Big Boy 6-11104; trying to fix intermittent chuff and fan smoke; opened it up; took out chuff switch and adjusted the lever down; installed again and have 4 chuffs/revolution from the tender. Did not do this before; however the fan pulses one time/revolution; the 4 chuffs/revolution are good but fan motor pulses only once. Replaced the fan motor; replaced element from 6 to 8 ohms; swapped R4LC to a new R4LC S03; no help. Thinking I have to replace the chuff switch; the good serial data to tender is and not to smoke unit to match is the curve I did not expect; wonder if I need a serial buffer to the smoke unit; will try to the new chuff switch (PITA to install!) Any input from the wizards here is appreciated; Falcon70