Re pollen filter, what determines blower motor compatibility?
 

On W124, which blower motor to get seems to depend on whether or not one has a pollen filter. Am I correct that, in both cases, the motor itself is exactly the same and that the difference somehow has to do with the squirrel cage assembly? If so, what is that difference?

diameter, and the housing it's mounted into.
85-93 124's get the large non pollen... 94/95 get the small with pollen.

That's good....do you think it's safe to assume that a blower assembly from a 93 300TE would be a perfect fit for my 91 300D?

The thing that confuses me is that, when I do online searches for parts, both options are given for my car.

Yes, any 1986-93 W124 chassis made for the USA uses the same blower motor & regulator.

That's good news. So, just curious...why do the various online parts catalogs give both options for a given car?

it's CYA... they don't know, so they leave it up to you to choose...:rolleyes:

It's funny....even the EPC seems to do the same thing. But, from what I gather, no W124 from 86-93 sold in US market had a pollen filter. Is that correct?

correct.
likely the FSM is an entirety volume. if you got one published prior to the 94 model, I bet it would not mention the filter...

The motors are the same as the old ones except for one bit, the non filter style has spade connectors on the motor to which the car wiring connects to.

The filter style has two wires that are soldered to the posts on the motor and have the spade lugs on their other ends which are then tucked under the holding clip. its done because the later style squirrel cages are wider and smaller in diameter which will not allow the wiring to plug into the motor directly.

You will find that the filter style blower assemblies go for a lot of money, best get a motor from an earlier w124, a hi performance solder iron to transfer the original tail wires, a small puller for the squirrel cages and replace it out.

A somewhat related question:

On the 201 if I open up the blower box, I have access to the evaporator.. Is this true for the 124? In my 201 the evap was full of gunk. I cleaned it and air flow was AMAZINGLY BETTER. I kind of want to do the same for the 124 but...

The W124 has the same arrangement. under the wiper is the blower, and behind the blower is the evaporator.

btw what did you use to clean it, (I dont require it as my car has the filters and the evap fins are shiny as new)

just for other users sake, Ive seen a very rapid expanding foam at a toyota dealership that is made for this purpose - it can really get through that grime - and I have literally seen a dealership use simple green HD or aerospace to wash the condenser and radiator fins. Made them real shiny and clean.

When I did my 201 all I used was my air compressor with blow off attachment. I didnt have any foams or sprays on hand at the time.