I am having a difficult time finding out what goes in the hole between the blower motor and the heater core inlet/outlet(not sure which one, it is the one on top) The factory assmebly manual shows a wire going to this device and connecting with the relay on top of the evaporator unit. It fits in a round hole and has one screw attaching it. Does anyone know what this is and where to get it? Ricks tech line could not tell me what it was?

Sounds like its the reostate, small block with a plug for thre wires, on the underside it looks like a couple small springs, this controls the blower fan speed.

otherwise known as a Blower Resistor, the 69 Factory Air had a special resistor with 4 connectors (to control 3 fan speeds, relay gave full 12-14.4volt for 4th speed).
According to everyone on this board its not in production anymore so I bought myself a 69 NON AC Resistor (2 speeds + relay third speed) so I lose my lowest speed setting.
Unfortunately its not an instant hookup, you will need new connectors or solder the wires directly to the connection of the nonAC resistor. Originally AC Resistor was a single 4 connector in a T shape, non AC resistor version uses a 3 contact (2+1) connection instead which either you will need to find the connector for, remove from a nonAC car in the junkyard, or get 3 separate connectors that work (best solution)
Its a very simple device, just two resistors basically (original one had 3 resistors), and basically provides 2 different voltages to the RELAY so that the relay will have the ability to provide a particular voltage to the blower motor, thus giving you different speeds.


Classic Industries
GM Part : G5093
$5.95

Also available from your local GM dealer
http://www.parts123.com/parts123/yb.dll?parta~showpic~0000136b~BAHGO~~~

The blower motor resistor attaches with 2 screws and sits on the top of the inner half of the evaporator housing, commonly refered to as the suitcase. On the other side (fender) of the housing about halfway up the side is a low temperature switch (P/N 3917359) that disconnects power to the compressor clutch when the air temperature gets down to 29 degrees. This is held on by two screws and has two wires on it. One is tan and comes from inside the car, the other is dark green and runs to the compressor clutch.

The only other wires on that side of the housing are the power and ground connection to the fan motor. The ground has a slip on connector with a circular rubber grommet that slips onto a male connector, rivited to the flange of the motor housing.

Right on, Mark C... that's what I was going to say. graemlins/beers.gif

Mark did you mean the POSITIVE connector has the round rubber slip over wire end? At least thats what mine has, the negative is grounded to a tab off one of the bolts holding the motor housing.
For future reference I want to make sure this is right, mine started to work now with that lo blow issue resolved. graemlins/thumbsup.gif

The positive cable attaches to a terminal on the top of the motor itself, the negative cable attaches to the terminal that if rivited (mine) to the flange of the motor, where it attaches to the fiberglass suitcase. Both of mine have rubber boots over the connector.

Thanks for the info. I figured it out with the help.