Also - the top bearing can be purchased online - we had one that howled horribly, and even after being cleaned and soaked in oil, it was still bad. So DH has one on order from Sew Classic, I think it was under $5. This is off a machine that we know had been "serviced" and then given to the DIL and DIL never used it, so it sat and everything hardened up over the next 10 years.
Not sure what the service guy used, but the machine has been one of the worst to clean as the grease/oil hardened up really bad.
BTW - my husband considers the 401 to be Singer's Ultimate design.