Repairing oil boiler motor

[Ben ten ten]

When the motor stops working on a oil boiler. I know the most common fault is usually the capacitor, but if the motor is actually faulty is it usually the motor bearings that go? I am asking, because I see you can buy motor bearings, instead of buying a whole expensive motor. Has anyone replaced them before? How hard, or easy did you find it was to do? I also see you can buy bearings for the fan side, and the pump side, should you replace both? Thank you any help with be greatly appreciated.

 

[Burnerman]

Dead easy to do, with the motor on the bench, obviously......separate the motor casings by removing 3 or 4 screws, pull the casings apart. (No brushes to worry about). Often enough, the bearings come out with the motor armature but they are easy enough to carefully drift out of the aluminium casing if they remain.
Replace both bearings......6202zz is a popular size.
I've never had a bearing seize, but have replaced many noisy ones......its not often that the bearings stop the motor!
John

 

[Ben ten ten]

Hi burnerman.
So I am wrong in thinking I can repair motors simply by replacing the bearing(Obviously after confirming the capacitor is not fault)?
What other things can I do to get a motor working again?
Do you often get motors that will not work, or in most cases is it simply replacing the capacitor, or replacing bearings to stop motor noise?
Thank you for your help.

 

[Burnerman]

Ben, if you have the motor on the bench, try spinning the spindle by hand. If it spins easily the bearings are fine, apart from they could be noisy. They certainly won't prevent the motor starting up. If the spindle is tight, then its quite possible they are old and lacking in lube.
A test......with the motor safely connected to 250v and it doesn't start, try spinning the spindle in the normal direction of rotation, and see if it starts up.....this is really the job of the capacitor, of course.
If the motor is spinning but doesn't seem to reach 3000 RPM, or its easy to stop the spindle spinning with your fingers, its goosed.
Shop around if you need a new one......prices vary from £35 to £100 for exactly the same thing
I've had probably equal failures with capacitors and motors, although I see very few now - and have repaired many a howling motor with dud bearings, probably due to the temperatures at which they run!
Carefully does it, regarding electrical safety!
John