[T3] Blower Motor

[Jim Adney]

On 8 Dec 2016 at 12:34, William J wrote:

> Guess I was wrong. I looked at the Bentley and it shows what looks like a 
> capacitor and something that may be a resistor both on the low speed circuit 
> and only one winding.

Yes, that's a capacitor, which would have been for electrical noise 
reduction, to reduce radio interference. I don't recall seeing that, 
so I don't know where it is or even if it's really there.

Yes, that's the resistor, only in the '73 schematic. It's just in the 
low speed circuit. The high speed circuit bypasses the resistor.  
IIRC, the resistor is hard to get to. I THINK you have to pull off 
the fan blade and it's under there. My impression is that it doesn't 
get enough cooling, so that's why it dies. There's actually a VW part 
number for that resistor and I actually have one, but I replaced mine 
with an Ohmite brown devil, perhaps 1 Ohm. That lasted quite a few 
years and then also failed. I've ignored it since then.

I don't know why the low speed contact on a switch would fail. Is it 
possible that your resistor had failed, making your low speed no 
longer functional (like mine.) If you had blamed that on the switch, 
replacing the switch would have made no improvement.

In any case, the better repair is to swap in an earlier fan and box. 
There were multiple changes done in '73, and each of them makes the 
earlier boxes more reliable. Anyone who does this should pull it all 
apart, clean it out and lubricate the fan motor bearings.


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Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
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