Originally Posted by mainah
You can take the motors apart they use bronze bushings that were impregnated with oil of course they dry out over the years a good cleaning of the shaft and some light grease and your good to go for a few more years.
Take a bow Mainah. Was warm today so I decided to dismantle the furnace and try your suggestion of re-oiling the motor bearings. Real PITA to get the blasted thing out where I could work on it. Thankfully I took many digital photos of the dis-assembly process, especially the wiring.
It comes apart rather easily and the fans slipped off the shafts with a little encouragement (and a few curse words). The ends of the motor are a bit more difficult to remove to access the bronze bearings. Actually I gave up on the exhaust fan end and just pried it up enough to inject some oil into the felt? around the bushing. The other end came off easily so it got more oil on the felt? and the shaft.
Just to be sure the fix worked I tested the motor using my car battery and let it spin rapidly for a few minutes. Re installed everything clicked on the thermostat - and NOTHING!!! No fan spin, no voltage on the board.
Pulled it back out far enough to check all wiring and everything was hooked up correctly. (those digital pics came in handy) Hooked everything back in place and decided to try thinking beyond the furnace. Yeah! Check the fuses stupid!!! Replaced the blown fuse and all is now well. Don't know when the fuse blew but it happened while I was futzing around taking it apart and was not the original problem.
Thanks again for that thoughtful, experienced $84 saving suggestion. I was able to cancel the order for a new one before it shipped.
And yes if anyone asks - it took a long time working in such a small space. Maybe six hours figuring it out the first time. Could do it again in 30 minutes. Ain't experience wonderful!!!!