STOCK 91 Explorer 4.0L 4x4 Blower Motor r & r
Some folks might think a failed blower motor is just a "comfort issue" involving the heater and A/C - but it is also a safety issue when you need that defroster to clear your windshield!
Apparently there is a difference in years, particularly on the location of the relay. Since I just finished a r/r on my 91's blower motor thought I would jot down some thoughts on that particular year.
Problem - kept blowing fuses - fan would operate on high position only then blow the 30 amp fuse in the interior fuse panel under the left side of the dashboard.
Replaced the "blower motor resistor" (had to go to Ford and spend a bit over $17 as neither AutoZone nor Kragen had them listed as available). That resistor is located within 8" of the blower motor itself and permits the various speeds for the fan to work. Long story short - blew it also. "Something" was *causing* it to blow and I was running out of time (the wife drives it to work each morning).
Since time is $ too - I simply gathered up a new A/C Relay - another Blower Motor resistor - and a new bower motor itself.
On my 91 - the relay is located on a bracked located underneath and upside down under the main power distribution box attached to the right-front fender. It took a bit of prying to get it loose and I found it necessary to remove the power distribution box first - THEN remove the relay box I found underneath it (this was due to the associated wiring coming in from different directions).
The blower motor is only held in with 3 screws, but you have to remove the air-filter box to get it out of there. I removed the two screws holing the lid, plus one more screw on the engine side of the box and by looking closely was able to see it was just held in with a pair of plastic nipples extending through two flaps with holes in them on the "fender side". A bit of careful prying and I was able to raise the "fender side" of the box up then remove it.
The blower motor is a snap to get out of there - again only 3 screws and a single plug - but there IS a little 5 inch rubber hose that extends from the fan housing back up to the fan motor that you need to remove (pull off) and save. Presumably, its purpose is to take some of the air from the fan and use it to cool the rotor/stator on the motor itself.
My new blower motor box contained only the motor and mount plate - with no other parts what-so-ever. I carefully removed the "squirrel cage" fan from the old one and salvaged the retaining clip and the rubber gasket which was still in good shape - then put it on the new motor. Used small strips of electrical tape to hold the gasket in place during replacement later on.
With the motor still out of the vehicle (giving me a bit of room to work) I went ahead and replaced the freshly burned out blower motor resistor with the "brandy new one".
Re-assembly was a straight-forward reverse process. The new blower motor works fine in all switch positions.
Of course, now I find I'm going to need to re-charge the A/C system, but there are already some pretty good articles in here on that procedure nd I don't foresee any problems with that part.