Hey I have a quick question.
The blower on my 91 explorer has been acting up lately. The heater and A/C work great but the blower doesn't turn on all the time. Sometimes it will turn on when you start it and sometimes it wont' come on until you are almost to your destination. It can be a hazard now that winter is here and need the heat and defrost. I would like to solve this problem myself. Got any good ideas?
When you're having the problem, do any of the speeds on the blower work?? If not, it sounds electrical, or perhaps the motor is locking up. Try rapping on the motor to see if that gets it going. That may help you further diagnose the problem.
Located with the speed control resistors, there is a thermal fuse. This is the same kind as in hair dryers and coffie makers. Radio Shack sells replacements for about $2. Because it is chemical, some can become intermitant when old. Looks like a metal diode. If it is bad, crimp a new one in. Soldering will pop it!
A co-worker had the same problem . . . I suggested cleaning the ends of the armature in the bushings. He did it the easy way and says he has had no problem for a month now. He simply drownded the bushing areas with WD40. He got a lot of black run off and put the blower ***'y back in. He's happy for now. I wouldn't expect this to be a permanent fix but it should get you going quick and cheap and actually last a good while. Possibly a couple years.