IIA Transfer Case Problem

[Series3 GT]

My IIA won't go into 4WD high all the time, I press the yellow lever down and sometimes it'll stay down and go into 4 high and sometimes it won't stay down and stays in 2WD. It goes into 4 Low no worries and changes between High and Low without a problem it just won't go into High Range 4WD all the time.

[JDNSW]

Most likely rust or possibly just mud on the selector shafts sticking out the front of the transfer case extension. Especially likely to be a problem if the dust cover is missing. Should be easy to clean up and lubricate, although removing the RH floor and possibly the transmission tunnel would make it easier.

There are other possibilities, such as a broken spring internally, but as far as I can see these would give a permanent fault. Of course, no oil in the transfer case could also cause it, but I assume this is not the problem.

John

[Series3 GT]

Well it's still got oil and as I said it's not a permanent thing. With cleaning the selector shaft it's the yellow lever that's causing the problem I think because when I push it down it won't always stay down. When I put the Red lever into neutral it goes down and stays down but of course as soon as you put it back into high it goes back into 2WD.

[jerryd]

I recently had a similar problem with my series III transfer box and have just fixed it , it turned out to be one of the rods jamming due to dirt/rust/grime. After lots of persuasion by cleaning, oiling and a big hammer to free it, it now seems to be working okay again.

If you remove the small cover at the front of the transfer case you can see the rods moving, or not moving.

[d@rk51d3]

Well it's still got oil and as I said it's not a permanent thing. With cleaning the selector shaft it's the yellow lever that's causing the problem I think because when I push it down it won't always stay down. When I put the Red lever into neutral it goes down and stays down but of course as soon as you put it back into high it goes back into 2WD.

Pushing the lever into high is supposed to release the yellow back into 2wd.

It does sound as though something is a bit sticky.

[JDNSW]

There are three selector shafts. The inside one, nearest the gearbox, is the hi-lo shaft, carrying the selector fork. It also carries a link to the middle and outside shafts and via a spring a sleeve connected to the middle shaft. The outside shaft is the front drive dog shaft, and carries the selector fork between two springs.

When in two wheel drive the middle shaft is held from moving by the yellow knob via a lever and a pin dropping into a hole in the middle shaft. When the yellow knob is pushed, the pin is lifted, allowing the middle shaft to move forward under the pressure of the spring on the hi/lo shaft, in turn via the link carrying the outside shaft forward and engaging four wheel drive. As the pin is no longer over the hole, the yellow knob stays down. If it does not stay down, there are only two possibilities. Either the pivot the lever that lifts the pin on is missing, in which case it would be a permanent fault, or the selector shaft is not moving. This is almost certainly because it or the outside shaft that is linked to it is sticking due to dirt or rust.

As I said, remove the dust cover on the front and free these two shafts.

John

[Series3 GT]

Thanks for the help, Can I try to oil the bit that the pin holds down from the opening in the top or is there no avoiding the removal of the dust cover. I'll try something tomorrow and let you know if it works. As you said remove the dust cover but I'll see what I can do. I'm not sure it's actually there the dust cap I'm not entirely sure what it looks like.

[Series3 GT]

Pushing the lever into high is supposed to release the yellow back into 2wd.

It does sound as though something is a bit sticky.

I know it's supposed to go back into 2WD but thanks anyway. I just read another response from JerryD that the dust cover could be missing and it is becaus I can see the linkages.

[JDNSW]

If the dust cover is missing, this will make it more likely that the shafts are sticking - are you sure you are seeing the shafts - the dust cover has a separate tube over the middle and outside shaft, so unless everything is very clean, it is hard to be sure without your seeing movement during operation of the levers.

You can try putting penetrating oil in the hole the locking pin goes into, but it is unlikely to work.

John

[Gumnut]

I had the very same problem many years ago. The spring driven shaft was well seized in the housing.

I ended up stripping the xfer box, and replacing the corroded shaft with one very easily manufactured from a handy bit of stainless rod (1/2 or 9/16 from memory) that was very co-incidentally laying around the workshop. It's lasted another 30 years or so with never a problem.

Although I once had a mechanic advise a potential purchaser that there was a problem with the transfer case on a IIa I was trying to sell because "it wouldnt stay in 4WD in Low range because the yellow knob kept popping up". The potential purchaser would not listen to reason, or even read the instruction plate. Needless to say, I spoke to the mechanic, and he listened patiently to my careful explanation, and said "well that's not what happens to the one on our farm, and it's fine!" I pointed out exactly what was probably wrong, along the lines of JDNSW's explanation, and he said it was probably a different type of box........ It was a dad and dave outfit that is long since shut down.

Andy