[TMC] Rotron blower

[Richard Knoppow]

     Just guessing here.
     First of all what kind of bearings are used, i.e. ball 
bearings or sleeve bearings.
     I am assuming the blades are not bent. Can you move the 
shaft back and forth with your fingers? That should tell you if 
there is end play and perhaps give a clue about the noise. Also 
wiggle the shaft around in the baring to see if its just loose.
     Do you have access to something like a General Radio 
Strobotac, if so it may be possible to see what is moving.
    The Rotron fans I have had experience with were small with 
sleeve bearings of the Oilite kind. I was able to relubricate 
them using turbine oil. Turbine oil is very highly refined 
machine oil. About SAE 20 machine oil should work ok.

On 9/27/2019 9:58 PM, Robert Nickels wrote:
> I'm looking for tips on noisy Rotron blowers, the one in question 
> being used in a PAL-350 amplifier.   I was told that bearing 
> replacement is often needed so I got some new bearings and 
> replaced them, but the rattly metallic noise continues unabated. 
> The position of the armature between the end bells seems to be 
> determined by shim washers in each end, and I kept the same 
> number in the same place as originally, but is this something 
> that is tweaked for each motor?    I'm sure I didn't get the 
> bearings in precisely the same position on the shaft but assume 
> they move as needed when the end bells are attached and 
> tightened.   The motor starts and runs fine and produces plenty 
> of air, it's just this mechanical noise in addition to the 
> expected white noise of normal airflow.
> 
> 73, Bob W9RAN


-- 
Richard Knoppow
1oldlens1 at ix.netcom.com
WB6KBL