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.