Fr8trplt

I recently did the RetroAir ac upgrade on my 85 Carerra Targa. Bought the delux Kit which included a new 3 speed blower motor. During the upgrade, I removed the resister at the bottom of the "smuggler's box" footwell are and wired blower to existing switch as instructions dictated.
Blower runs great on all three speeds, but the switch body becomes too hot to touch for more than about 3 seconds. RetroAir had not run into this when I called. Is there a switch replacement/resistor necessary? Any thoughts would be appreciated. My car has great AC now (it is 100 degrees here today) but a cabin fire caused by an overheated might warm things up a bit.

griffiths

Assuming all of the connections are 'good', meaning where you connected 'terminals' or spliced wires there is sufficient copper or contact area to carry the amperage you might want to look at 2 things:

1) The amount of current or amperage the motor draws on each fan speed.
You could use simple amp meter with a 'clap' however a inline amp meter works best. You would put the amp meter in line and test each its 3 fan speed wires to see how many amps each circuit is drawing and discuss that with the motor supplier.

2) If you have an original 3 speed fan switch the contacts are worn or oxidized and they are causing the the switch to heat up. If so you an buy a new OEM 3 speed fan switch on Pelican Parts.

rstarga

I had the same problem until I got a new switch, just as Griff says.

CarPartsDiscount.com

This is kind of on the same note as griffiths but when i have run into something like this in the past it has been due to either a bad connection (either a loose wire, too thin of a gauge of wire, or corrosion) or a switch that is not rated for that much direct power. is there a relay inline for this switch? if not there should be.

griffiths

Yes, corrosion in the circuit or a frayed wire can do this as well, such as the primary AC fuse terminals, and the primary AC relay.
As I recall the brand motor you are noting has 3 separate circuits (the motor windings) to control speed and the OEM fan speed switch
simply directs the current to the specific winding.

Again, assuming all of your connections you made or changed are good, and you did not have an issue using the old stock motor with the
current switch, then I would suspect the motor. Ask the company that sold you the motor what the max amp draw should be on each of the 3 fan speeds
when the blower wheel is attached mounted inside the evap box.