Rear locker locks then unlocks (1 Viewer)

[cybrstar]

I’ve searched and couldn’t find what I was looking for pertaining to my issue.

My rear locker was locking and unlocking just fine before I went through the Con last month and right after Cadillac hill I noticed that my locker suddenly unlocked and the locker light started to blink. I didnt hear anything brake but just a “click”, same sound as it unlocking.

So now when I try and lock my rear it will lock, but when I try to hit an obstacle it would just unlock, sometimes, and I have to turn the locker off and then turn it back on to lock the rear again.

So I ask, has anyone ever had this issue? I’m pointing at the actuator right now, maybe not pushing the locking mechanism far enough which is causing it to unlock. I know it’s not the locker because the locker will stay locked.

 

[Dave 2000]

Almost certainly the actuator is travelling far enough to stay engaged.

But check cables as they enter the motor for breaks and corrosion.

If is the original then you might want to spray a release agent around it for a few days.

Bolts don't like moving after 20 plus years.

Once out a good clean and pack with chain grease, should be good.



Regards

Dave

 

[Pin_Head]

They don’t just unlock. The actuator motor has to run the other direction to unlock. Are you sure it is really unlocked or is the light just blinking? It might be a sensor issue.

 

[cybrstar]

They don’t just unlock. The actuator motor has to run the other direction to unlock. Are you sure it is really unlocked or is the light just blinking? It might be a sensor issue.

It’s not the sensor because I can feel I unlock when I try and move forward as only 1 tire spins.

I may also note that I had the rear light blinking and checked it out in my garage. I raised the rear and rotated 1 tire back and forth. Once I heard the locker engage both tires locked and the light stayed on. So I know the sensor works.

That’s why I’m pointing at a weak actuator.

 

[Pin_Head]

There is no such thing as a “weak” actuator. The light won’t stop blinking until it is fully locked.

 

[cybrstar]

Maybe shockload on the differential causes it to unlock?

 

[Pin_Head]

It is probably time to remove the actuator and check its function.

 

[cybrstar]

So I took the actuator out and greased/test it’s function and it seems to work. There was no corrosion inside, magnets looked good. I didn’t take off the coil area because I didn’t want to mess with the spring.

When 12 volts applies the piston would move from 2 1/16-2 7/8 inches, which is a normal range from what I researched.

Here is where I think the problem lies. The picture below is when 12 volts are directly applied to the actuator in full out position. Picture shows very little gap between fork and housing, which locks securely.

This picture displays the shifter fork position when the lock switch is bolted in and the factory diff switch is on the on position. I did this about x3 and notice the 1/8 inch space. The once the fork hits the diff light switch the motor is stopped. (BTW, this picture was taken on the second try, the first had about 1/16 more of a gap, but could not duplicate on the third try)

Would this cause my locker to “not be fully locked” and unlock when shockload is introduced?

I haven’t tried it out yet on an obstacle so I don’t know if greasing the internals helped. I did notice that the locker actuator move a lot faster after greasing.

 

[Pin_Head]

From the RTV on the mating surface, it seems that someone has worked on the actuator before. If so, maybe he screwed up the alignment or timing of the actuator rod. This is critical measurements because it determines how far the fork moves. There is a write up on how to time the rear actuator that you can search for the user Raven Tai.