Heater blower fan noise squeal

[tomnj]

My 850 coupe has the dreaded heater fan "squeal", especially when it's very cold out (when you really need it). It gets better as the heater box warms up and doesn't squeal at all in temps above 45. Is there any way to squirt some lubricant into the blower or some other way to help silence it? Or am I looking at disassembling the entire heater box under the dash and replace the motor?

I remember my 124 Spiders had the same issue years ago. The funny thing is, the fan continues to work, it just goes slower. I noticed revving the engine (more power) seems to actually help it go away. Almost like a low voltage level is making it worse.

 

[ghostdancing]

i guess you should disassembly the heather box and have a look to the motor; will be the chance to look also at the radiator, valve and clean the entire system.

 

[Frank L. Di Gioia]

Years ago when I first got my Air Conditioning business going I did service work. A great many outdoor condensing unit fans displayed the same symptoms and SOMETIMES could be "fixed" by pulling the motor and dripping oil down the shaft end. The opposite end was normally sealed but a very SMALL hole could be drilled, oil forced in, and sealed again. There is a felt pad that will adsorb oil thusly applied. I only did this in what I considered "charity" cases- retired, Vets, those simply not able to afford new motors/fan blades. I charged only the standard service call, if that. The DOWN SIDE is sometimes they would work fine for a month and quit. I always warned this could happen and never got a complaint. I'd suggest this route IF a replacement motor is unavailable or costs more than the car. There are similar tricks to extend the life of SOME compressors a year or two for $5 that also work. As gohstdancing suggested do a complete overhaul if you do get in there!