RV Repair: suburban SF 25F furnace, combustion air, high pitch

Question
QUESTION: After reading your comments on how to remove the furnace i got it out. the unit has had a high pitch squeal that i thought would be a bearing on the fan unit. after removing it and rehooking power it still makes the noise but i cant tell exactly where it is coming from. after a little frustration i banged on the combustion air unit and it stopped momentarily. the manual that came with it said the bearing are sealed and need no lube. how can i tell which portion of it is making the noise

ANSWER: You will have to replace the fan motor assembly because the bearing is not serviceable.

Unless you feel like tearing down the unit and disassembling the fan.  If you have an industrial supply store in your area who specializes in bearings, you may be able to buy one there.  

If you decide to replace the assembly, you will need some numbers off the unit.  Google the model number and you will usually find parts inexpensively.  The good news is, you have already done the hard part.  It should go in easier.  

Good luck with your repair.  

---------- FOLLOW-UP ----------

QUESTION: So just the motor or all the assembly? Thank you for your help

Answer
the problem is probably a bearing.  If that bearing is in the motor, then just the motor.  If that bearing is somewhere besides the motor itself, you probably will need to replace the assy.  I am not sure what your fan body looks like.  So I cannot tell you more specifically what needs replacing.  Good Luck.