i have an np 241 dhd in my '01. when i bought it the 4 wheel drive worked. when the snow started to fall i realized now it doesnt! when i shift into 4x4 it doesn't engage the front drive shaft. i also lost heat controls. so i know there is a vaccum issue. but does the transfer case itself need the vaccum lines to shift into 4x4 at all? i pulled the case last night and im not sure if it is supposed to shift into 4x4 at all now that its not installed. and does anyone know where i can find a diagram of some sort for the vaccum lines or where they run? i know a few spots to find them but im not sure of the whole system. any help would be greatly appreciated!

 

There is a vacuum collar at the front axle that engages and locks the axle shaft on the passenger side together... No vac, no 4x4

 

yea i know that but does the transfer case itself need vaccum to engage into 4x4?

 

No, it's completely mechanical. Are you sure it's not engaging?

 

Well when I shift it into any gear the front driveshaft spins freely from anything else...which if it was engaged the front shaft wouldn't spin unless the rear was as well. So I'm figuring the tcase is junk but it doesn't make any noises or anything...

 

Sounds like your front axle isn't slipping into lock. Check the vacuum lines from the back of teh front axle, passenger side, on mine one is red and the other is blue and trace them backwards to the firewall and to the transfer case.

 

So I had the tcase out last night and when shifting it none of the gears will spin the front shaft..does that mean that just the chain connecting the rear and front is broken? But it doesn't make any noise and it never has...

 

You'll have to crack it open to be sure but that is what it sounds like.

IIRC the chains are about an inch wide and have a four or five row link set up so its wierd if it came apart silently...

You may have sheared a shaft, if it was clean and straight thru it will wtill allow things to turn.

 

Here is a part breakdown pic for the 241. Might be of some help.
http://www.drivetrain.com/images/sto...e/np241_lg.jpg

Something internal is not working correctly if you can't get the front yoke to turn. Highly doubt that the chain is the problem as I used 4x4 for several winters with my tc chain jumping teeth, it's awful loud bang and it never broke.

 

Thanks for the link...I've never taken a tcase apart but I do all my own mechanical work and can figure things out to an extent...is pulling it apart something a beginner can do? I gotta learn sometime right?!

 

I would say just take your time its easy not much to the np241 hardest part is lining up the oil pump tube when your putting the case back together. There is no gaskets just gasket maker and that adds to the difficulty of putting the cases back together.

 

here is a internal pic

 

Yeah that chain is a lot beefier than I remembered.

Let us know what you find.