4X4 selector problems / questions!

[nicsrover]

I don't think my 4 wheel drive is working. I have the car in gear and front wheels off the ground but I can hand spin the front wheels when it should be in 4x4!
My understanding is when you push down the Yellow knob you have 4x4 high, (it lifts up the locking pin). You then pull back the Red lever and the Yellow should pop up (pushing down the locking pin). I have taken the spring off the yellow knob and pulled it up so it clicks in (detent?), but I cannot pull the red lever back. If I push down the yellow knob then I can pull the red back int neutral and 4low (but I can still spin the fr wheels). When I push down the yellow then the red moves through the 3 positions.
I hope this makes sense - but it seems to me something is wrong.
The main gearbox works great and even in low - but I don't think its in 4x4, just low gear to rear wheels.
Any ideas of what to check or another way to test?
Thanks.

[RustCollector]

Can you clarify: when both wheels are up and spinning, are they spinning in three same direction? Can you also check by spinning the front prop shaft, or observing the front prop shaft is also spinning free when the wheels spin?

[nicsrover]

Can you clarify: when both wheels are up and spinning, are they spinning in three same direction? Can you also check by spinning the front prop shaft, or observing the front prop shaft is also spinning free when the wheels spin?

The front wheels are definitely connected to the front prop shaft. I think I now realize if the front wheels are off the ground they will spin due to the diff. So maybe I have to test the 4x4 on a gravel surface. It just seems strange that the levers seem to operate differently than they should. Can you tell I'm new to Land Rover series 4x4 systems? My yellow lever does not stay down with the spring on but I think it is the wrong spring and too stiff.

[SafeAirOne]

Just jack up ONE front wheel and see if it turns with 4WD engaged. It shouldn’t.

[nicsrover]

Just jack up ONE front wheel and see if it turns with 4WD engaged. It shouldn’t.

I can turn the front propshaft with 4wd engaged - I guess it shouldn’t do that.

[SafeAirOne]

My yellow lever does not stay down with the spring on but I think it is the wrong spring and too stiff.

The spring is a very stiff one. Even if it’s the wrong spring, it can’t possibly force the yellow knob up (back into 2WD) once it is in 4WD high has been properly selected. Here’s why:

If the system is working correctly, fully depressing the yellow knob pulls a locating pin out of a hole in a spring-loaded shaft inside the T-case. With the locating pin withdrawn, the spring-loaded shaft springs forward, taking the hole in the shaft out of alignment with the locating pin. The yellow knob will not be able to be raised again until the hole in the spring-loaded shaft is brought back into alignment with the locating pin. This can only be accomplished by pulling the red lever all the way to the rear (4WD LOW position). Once this is done, the pin will drop back into the hole in the shaft, giving the yellow knob the freedom it needs to spring back up. Soooo…

Make sure your red lever is all the way FORWARD or else the yellow knob will not stay down.



The operation of the transfer case controls are not intuitive to someone unfamiliar with Series Rovers. Here’s what you need to know:

1) The yellow knob’s sole purpose is to engage 4WD HIGH. It has only 2 positions: UP=4WD HIGH NOT engaged and DOWN=4WD HIGH engaged.

2) The red lever has 3 positions:

FORWARD position is HIGH gear (either 2WD or 4WD, depending on the position of the yellow knob),

CENTER position, which puts the transfer case in neutral, essentially disconnecting the everything downstream of the transfer case from everything upstream.

REAR position, which pops the yellow knob out of 4WD HIGH and engages 4WD LOW.

Generally it all works like this: You’re driving along in 2WD and see that there’s an obstacle that’ll require 4WD to overcome—deep sand, for instance. You come to a stop and push the yellow knob down, engaging 4WD high gear to cross sand.

On the other side of the sandy area, you find some steep rocks that’ll require some extra grunt to crawl over, so you come to a stop, then pull the red lever all the way back, disengaging 4WD high (yellow knob pops up) and engaging 4WD low gear.

You traverse the rocks, and on the other side of the rocks is a hard packed gravel road, so you come to a stop and push the red lever all the way forward into 2WD. You can either drive off in 2WD or mash the yellow knob down to drive off in 4WD high again.

[series guy]

Sounds like you are in for a very common Rover repair which costs little if you do it yourself. Mark explained the function of all the levers and gears. But if as you mentioned the yellow knob does NOT stay depressed then the spring loaded shaft is not moving. This is pretty common. The unfortunate part is that the repair requires the removal of the floors and transmission tunnel. There is a tin cover on the front of the transfer case retained by 2 bolts and the pin controlled by the yellow knob. Remove this cover, clean out all the mung and gruel and then clean and lubricate said shafts. You may need some percussive persuasion to get things working. Reassembly is the reverse of this procedure.

[SafeAirOne]

I can turn the front propshaft with 4wd engaged - I guess it shouldn’t do that.

These transfer cases are pretty bulletproof.

In order of likelihood, I’d check:

1) transfer case in neutral
2) transmission in neutral
3) little round selector shaft dust caps on front of T-case for damage
4) selector shafts inside transfer case for binding.

EDIT: UGH…after all that blathering on I did in the previous post, I Just re-read your original post. Looks like you have a pretty good grasp of theory of operation. I’d focus on items 3 and 4 on the paragraph above. The only other thing I can think of would be a broken spring on the high/low selector shaft, but that’s super-unlikely, compared to 3 and 4 above.

EDIT AGAIN!: Looks like Series Guy beat me to the punch by 1 minute regarding the dust caps.

[Paul D]

A photo of the transfer case shafts with the cover removed. It took a lot of cleaning, PB Blaster and 'Percussive Therapy' to get these free.

[72Rover]

Make sure your red lever is all the way FORWARD or else the yellow knob will not stay down.

One other note on the functioning of the red lever - especially if it has been removed recently. The bottom fixings of the bracket attach to the front of the bellhousing, not the rear, which common sense would dictate. It's only a 1/4" difference, but that little bit throws off the whole 'geometry' of its operation.

Cheers

[series guy]

It’s funny that we all remember a different key part of the proper functioning of this component. Put us all together and you have genius level intelligence.

[nicsrover]

Here is a link to a couple of videos I made. I removed the dust cap, there is grease inside so it's not rusty. Any ideas or questions re: the video let me know. Thanks.
https://www.youtube.com/watch?v=nKsyN4-vSEY
https://www.youtube.com/watch?v=IugsHXVPWPs

[nicsrover]

One other note on the functioning of the red lever - especially if it has been removed recently. The bottom fixings of the bracket attach to the front of the bellhousing, not the rear, which common sense would dictate. It's only a 1/4" difference, but that little bit throws off the whole 'geometry' of its operation.

Cheers

Photo from below - Does it look right?

[SafeAirOne]

Here’s a crude video I made using Google sketchup a decade ago, before I knew SolidWorks. It shows what happens inside the transfer case when you shift from 2WD to 4 high, then pull the red lever to 4 low, then forward to 2WD again.

it’s a pretty short video, so use the menu to reduce playback speed to the slowest, and loop the video to repeat continuously.

the perspective is from below the transfer case from front looking aft. The pin for the yellow knob is located on the top left, between the selector shafts. It’s the first thing that moves as the video starts.

You’ll note that both selector shafts have to be free to slide in order to get the swivel mechanism properly positioned for 2/4WD and high/low gear.

From your description, the 4WD selector shaft (the one farthest away in the video) is bound and not moving forward when the pin is withdrawn from the swivel shaft:

https://youtu.be/Jz9uvVRFywk

I wish I had a disassembled transfer case to measure—I’d redo this video with a photo-realistic one created in SolidWorks that’d blow the doors off this crappy video.

[Ollies truck]

I had a problem with the yellow knob not staying down. I unscrewed the knob a few turns and it worked as it should. Check the hieght of the yellow knob on the shaft. If it is too short the pin won't withdraw all the way to allow the shaft to spring forward.