Rear diff lock doesn't engage. Help (1 Viewer)

[Swisscheese]

Hi guys

as i have mentioned in my thread about preparing the 100 for a trip through africa (Prepping my 100 for an Africa-Adventure) i have a differential lock which doesnt engage. presumably due to corrosion. today i wanted to take it apart to check for the acutal reason, but i didnt get really far. the three screws which hold on the lid do not move at all. wd40 didnt help, neither did any tool. how do you recommend me doing this?
here is a pic of the result after trying 15 minutes:

 

[Trunk Monkey]

You could try an impact remover. Doesn't look like you have much corrosion under there, have you tried working the locker out to coax in into engaging? If you get a blinking light on the dash at least, you could try driving big circles on a loose surface in a figure 8 to see if it will mesh up and engage.

 

[Swisscheese]

You could try an impact remover. Doesn't look like you have much corrosion under there, have you tried working the locker out to coax in into engaging? If you get a blinking light on the dash at least, you could try driving big circles on a loose surface in a figure 8 to see if it will mesh up and engage.

I have already checked engaging the diff while driving slowly whilst doing turns, but the light keeps on blinking. something must be stuck...
i agree, on the housing there isnt really rust, but this is party due to the underbody coating i did few months ago. also i couldnt really find another reason.. the previous owner did never engage the diff since he used it as towing vehicle. but i have to admit, i dont know what else it could be..

 

[Trunk Monkey]

If you've already tried that then you must have a stuck motor or pin. If you don't have an impact remover you could try grinding a slot in the head with a dremel and using a big flat head screwdriver.

 

[Swisscheese]

If you've already tried that then you must have a stuck motor or pin. If you don't have an impact remover you could try grinding a slot in the head with a dremel and using a big flat head screwdriver.

I'll try to get my hand on an impact wrench.
What will i encounter once it's open? what do i have to look for? what could be the stuck part and how do i recognize (and maybe fix) it?

 

[Swisscheese]

Yesterday i had an impact wrench at hand. I screwed off the protection cover of the rear diff lock and tried my best with the phillips head screws. they eventually wore out before the screw moved just even a bit. i the cut a slot so i could use the slotted screwer. it went better but before the screw moved the bit i used broke off. It just seems as these screws are totally locked up. WD40 doesnt help, neither did a plumber wrench.
What can i do? Suggestions?