Quote:
Originally Posted by funola
I have something similar to this one  9-50V 40A DC Motor Speed Control Module PWM HHO RC Controller 12V 24V 48V 2000W | eBay in my 85, not because of anything wrong with the resistor pack, but because of noise. With the fixed speeds, middle is too loud, low is ok noise wise but not enough air flow. With the PWM, I can dial in exactly what I need in loudness/ airflow balance.
The one I linked to ships from China so it may be a long wait. If you want one faster, you can get one shipped from the US but you'll pay 3x more for the same thing. |
It was probably on funola's recommendation (someone here recommended it...), but I have something almost identical in my 1983 240D. When I got the car on the road in fall, 2015, the 3-speed switch was wonky at best, and then it only ran on low speed.
First, I swapped my squeaky old blower motor with one from a Volvo 850, thinking that would also make it run on all speeds. The new one ran more quietly, but not at all speeds.
Then, I tried looking for a new resistor. They're NLA, and used ones (of unknown condition) are hard to find and expensive. Plus, I don't even know if it's possible to access the resistor with the dash in place. I can't find a diagram of it or instructions.
Then I considered installing a 3-speed resistor from another car - just slicing a hole in my airbox to mount it and then wiring it in. But, I didn't want to damage anything else by slicing the airbox.
So, anyhow, I installed one of these and I enjoy the infinitely-variable fan speed. Here's a video I did:
https://www.youtube.com/watch?v=j-oULis8cyI