88 bronco 4wd not working

[88xlt]

so i just bought this bronco for next to nothing runs and drives great (looks a little rough) but the push button 4wd doesnt work. the guy i bought it from said it did work up until the day before. the lights for the push button high and low dont come on and their is no audible sounds from the motor on the case. my question is this, is their an easy way to check the motor on the case without using an ohmeter, i do have a check light, and where are the relay and control modules for the 4wd? any and all info is appreciated thanks

 

[4.0B2]

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there are several ways to test several different parts of the 4x4. i'd start by testing the motor. w/out an ohms meter? volt meter... why would you want to? do you not have a volt meter?

 

[88xlt]

i looked through the tech pages and forums but cant find the specific location of the 4WD control module to test it, or the relay. i dont have a volt meter only a check light. am planning to take the motor off to clean and inspect it. just wondering if there is a simpler way to test the motor.

 

[wadus]

On the motor there is a cover that has wires going into it.
Take it off and remove the gear.
The gear has screw on the back side that is used for a "stop" to keep the motor from turing too far.
The screw has a plastic ring around it that breaks and lets the motor go past the stopping point.
I replaced the plastic with a small piece of vacuum hose and now the 4x4 shifts and works fine.


I'll try to dig up the writeup that I found when I did mine.

 

[wadus]

This is not the one i was looking for (its for an explorer), but it has all the info.

http://www.explorerforum.com/forums/showthread.php?p=1102904

The back of the large gear has a stud with a plastic bushing (cushion) over it that hits the stop. This bushing is what can cause many of the problems with the shift motor losing its place and getting lost. What happens is, over time, this bushing gets deformed and allows the large gear to rotate just enough past the stop to make the computer lose track of the position. To make things worse, the stop wedge in the gear housing is too short to fully engage the plastic bushing, meaning the stop is only pressing against half (front) of the bushing. Here is a picture of this bushing on the back of the large gear. This shift motor hadn't gotten lost (yet) but the crushing is evident. Sometimes you can just flip the bushing over or rotate it so that a different part is getting crushed. Other times the bushing is hardened and broken into several pieces. This is the piece that I suspect is the main culprit behind many shift motor replacements. I think it is a shame that a piece that costs maybe a quarter can end up costing an unknowing consumer hundreds of dollars.

 

[88xlt]

thanks the article helps a lot havent took it off yet but i do understand how it works better appreciate the help