Strange combustion motor behavior

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Mar 11, 2011
Puyallup, WA
I bought my current combustion motor about 30 years ago. I installed it about 2 years ago. Gave it a few drops of oil before installing. It’s a Fasco motor with the enclosed housing, old style. It ran fine for about 2 years then, all of a sudden, it was slow to spin up. The longer it sat idle the harder it was. I’ve had to use a skewer to help spin the blades to get it started, worked well. Now, after about 4 months of that behavior, it all of a sudden runs as normal. No hesitation on startup. I’m not a motor guy so I have no idea why it would act like that. I bought a replacement motor, no enclosure, thinking I would have to replace it soon. Now my dilemma is should I replace the old motor anyway even though it’s running fine. That’s probably the smart/safest choice but I wanted to get a few opinions first on why the current motor acted the way it did.
My guess is the grease in the bearings dried up. No idea why it suddenly started spinning nicely.
These are not sealed bearings. There are two oil ports on the enclosure for the bearings. I don't know for sure but I don't think one is supposed to oil grease bearings.
Speaking from experience this year.... who ever installed the motor on my pellet stove installed it upside down so i could not see the oil ports so it was never oiled over the last several years since i owned it and probably not prior to me owning it.. Well it seized up and took out my controller board. So if it were me i would change out the motor much cheaper than a new control board..

On a side note once i noticed the oil ports i gave it a few drops of oil and it freed right up but the damage has already been done to the bearings. it would only be a matter of time before it failed again
was never oiled over the last several years since i owned it and probably not prior to me owning it
zrock of all the people I thought you did preventive maintenance on your stove
My stove has just finished its 22nd season and the blowers are the original
combustion does not have any oil holes but with a little know-how oil can be
injected into the bearings and the motor and fan are cleaned at least once a year
The circulation fan is also cleaned and oiled but it has 2 D holes for a couple of drops of oil
lol ya i do preventative maint but i do not oil any of my bearings unless i see a oil port and even then im iffy... every single time i have ever oiled bearing that are in a dusty or dirty environment like this they fail.. When i pull things to see what is going on i see that the oil has attracted dust and ground out the bearings.. If i do oil i use sewing machine oil since its one of the few oil's that was designed not to attract dust and dirt.
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