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Whirlpool Designer Style (top freezer) Model: ET18DKXZN00 s/n: EB1630766 Type: 18TFA92 mfg. 04-92 Evaporator fan motor has been getting progressively noisier for years, but still runs (98% of the time). New Motor Issue Waded through the Chinese junk on Amazon this past November and found and purchased a new Whirlpool genuine FSP 482731 MOTOR-EVAP. Motor made in U.S.A. (yay!): Bay Motor Products, Traverse City, Michigan. UL. Date of manufacture 050521. Fan blade is also made in U.S.A. and identical to the original other than a few nubs on the new one which would not affect operation. With the back inner freezer panel removed, the original fan spins Clockwise (looking straight at it from the front of the refrigerator). Bench tested the new fan: runs Counterclockwise. Blade is identical to the original: they did not switch the direction/angle of the blades. These are 120VAC shaded pole motors, so no way to reverse other than maybe disassembling and flipping the frame around, at which point the terminals are on the wrong side, requiring harness extension and possibly dealing with clearance issues. No note in the box about any sort of production change. Question 1: Does the direction of air flow on an evaporator fan matter? Original Motor Lubrication Issue Not knowing whether the air flow direction mattered and assuming it did, i returned the 482731. The original part number W2154419ZP motor bearing surfaces (and the rest of the motor) looked good—indeed it looks like a nicer, better built part, with a larger frame and coil. General Instruments AF4 29420-66, date code 92xx (could not read the week numbers, hence the x es). Disassembled the motor. Cleaned the bearing surfaces with Fedron®, my go-to aggressive petroleum-based solvent, discovered during my former home audio repair career and successfully used on numerous motors in turntables and tape decks, including shaded-pole motors quite similar to this evaporator fan motor. Re-lubed with Tri-Flow oil with Teflon®, figuring a thin oil would be good in this application, and with Tri-Flow being rated for use down to -53°C, able to work in ongoing freezing temperatures. That repair lasted from mid-November until 19 March (a day over a week ago as i type this). The evap fan had again been getting a little noisier in preceding weeks, then all of a sudden SQUEEEEEEEEEEEEEEEEE!: metal-on-metal high-pitched squealing: lubrication fail! Spent nearly a day in-depth researching the optimal lubricant for evaporator fan motors living in freezer sections (including here on Appliantology.org): no clear answer. When i asked Perplexity.ai the question: What is the correct lubricant for the shaft of an evaporator fan motor in a freezer? it answered: The correct lubricant for the shaft of an evaporator fan motor in a freezer depends on the type of bearing: 1. For ball bearings: Use a light bearing grease. Clean out the old lubricant with solvent first, then pack with the new grease. For sleeve bearings (also called oilite bearings): Use oil with a viscosity in the SAE 10 to SAE 30 weight range. Suitable options include: • Sewing machine oil • Turbine oil • 3-in-1 oil This is a sleeve bearing motor. Had some 3-In-1 Motor Oil (blue and white can) on hand, rated SAE 20. Re-cleaned the bearing surfaces with the Fedron (allowed to fully evaporate as always), then liberally applied the 3-In-1 Motor Oil. Bench tested: fine. Put it back together: fine. Now, a week later, the evaporator fan motor is again noisy, and is having trouble spinning up, suggesting this is another wrong lubricant for this application: too thick, at least at freezer temps. This appears to be a good quality motor in usable condition. Seems to me it should be successfully rebuildable and continue to run reliably for many more years, with a suitable lubricant and proper refurbishing work. Question 2: What is/are the optimal lubricant(s) for a shaded-pole sleeve bearing 120VAC evaporator fan motor which lives in freezer conditions? I look forward to your thoughts, and to reporting back in the future with what else may not have worked, and what eventually did work (i hope!). ~ Thanks ~