Hi folks,
I'm new to the forum so be gentle with me

I am planning to re-build the transfer case on my 2002 X Type 3.0 AWD.
As this is a week spot on Jaguars I'm sure someone has sorted this out in the past
As well as replacing bearings and seal's I intend to fit a leval/top-up plug on the side of the caseing (to the rear).
There is a vent at the top that can easily be converted for topping up but is not so good for setting the leval of oil in the box.

Has it been done before ?
What are the pit-falls ?

Any info will be greatly appreciated.

Rory

 

There is a vast amount of info on this link, that will assist you deciding where to put such a level indicator:

Transfer box

 

Rory, the problem with the transfer case is the amount of flexing that the case experiences. So, with that being said, any amount of metal that you remove from the case will result in even more flexing and more issues. How bad this is is dependent on more items than I could even possibly list with the big ones being location and amount of metal. So, I can not recommend drilling a hole into the casing to be able to add more fluid.

With that being said, some of us have installed valves in the drain port. From there, with the use of a little bit of tygon tubing, you can get the same thing and then use the tygon tubing to also add in more fluid. In my case, I have a 4 foot piece that I run down through the engine bay to the valve. From there, I can open the valve and let the fluid reach a level in the tube and as long as you mark a level on the tube after a fresh refill, you will know where the level should be. Then you can simply pour some fluid into the top of the tygon if you need to add more.

 

Thanks for all the help and advise.
Good link Astromorg - loads of info - thanks.

Thermo - well reasoned argument for not drilling the caseing. I'd not thought of the problem being down to poor casting allowing the unit to flex.
I'll probably follow your advise and fit a remote/tube fill up.
Rory

 

In that case, an important point to note is that the Jaguar's drain point leaves 250mls in the box. Don't go and add 550mls then wonder why the righthand drive oil seal has failed - it won't have; it will just be the vent blowing off the excess! (Been there, done that!)

 

Astromorg, thanks for the detailed write up on the UK Forum. A few questions.
You mention leaving 3mm of untapped thread area on the drain hole to help hold the magnet in place, but I see no magnet pictured.

Also, since you did do the drilling to get a complete drain, have you experienced any of the problems that Thermo brings up concerning flex ? I realize that this would more than likely mean a failure of the TC.

On a side note, has anyone considered filling from the top ? Meaning, locating the precise are to drill an access hole in the floor pan to get to the top plug ?

 

davis, the plug to fill the transfer case is sandwiched between the transfer case and the block. so, even if you managed to get a hole cut in the correct place, you still can not access the plug. So, as far as I can see, there is no desire to cut a hole like that. I'm sure one of the other members can bring up a picture of their transfer case and show how the plug is orientated in relation to the block.

 

Thanks Thermos, it was just a thought. Since we have no true way to drain these units completely I was considering the drill and tap method, your comments concerning this leave me concerned.

The one way valve idea is valid, but I hate removing the function of the magnet on that particular plug. Obviously, I will do something, and ultimately it looks like I will have to sacrifice the loss of that magnetic plug, unless I can source some type of alternative.

I am assuming that there is no way to feed a suction line into the lowest part of the TC, or that would have been posted. I really do hate having to tackle what should be a simple matter of drain and refill.

 

Davis, if you look at the photo of the new drain plug I made, it's an M6 bolt (6mm if you're not familiar with these sizings) that has a 3mm dia neodymium magnet fitted in the end and peened over to keep it there. These magnets are incredibly strong for their size and this one more than adequate for this job, despite its size!
With regard to the potential weakening mentioned by Thermo, I made a judgement call that a 6 mm hole in that position was unlikely to create or encourage a casing failure, so that's your call! I feel the benefits of getting a thorough 'box drain and then an accurate refill of all new oil is more likely to increase the longevity than the new hole is to shorten it!! I've had no problems.
In my opinion, almost all transfer box failures can be put down to inadequate lubrication, helped along by running without the cooling airscoop! You take care of the lubrication and the transfer box will look after itself!

 

Thanks Astro,

I am a little confused with the drain plug construction. Did you drill a 3mm hole into the end of the 6M bolt to accept the magnet ? How does peening the end hold it in place ?

 

Yes, you got it! Remove the thread from the last 2 or 3 mm of the bolt (I turned it off in the lathe) drill a 3mm dia hole, 4 mm deep and insert the 3 mm dia x 3 mm long magnet. Gently tap the edges of the hole over (Peen it) to make it permanent. Incidentally, I wouldn't use a drain any larger that 6 mm as the wall thickness of the casing at 7 mm is not thick enough to support a larger thread safely without stripping too easily. It's especially not thick enough, and this probably goes for the side walls as well, to take a 1/2 inch taper pipe thread as used as the original drain point.

 

Hi Rory,

I replaced just the 2 prop shaft bearings and races. As that was all my transfer case needed. I'd hate to see you overhaul the TC for no reason. it was a fairly simple matter to do the job, and the result has been fantastic.

In any case, search for my posts on the subject, I list the part numbers that fit my TC. And, of course how I did it.

I found the oil level is not that far off the fill port in the side. In fact, adding too much oil is the result of following some advice on this forum. If you actually take the TC completely apart, then fill it with the specified quantity, you will find the same, I promise!

 

Thanks for the info Cujet.
As yet I havent started overhauling the TC unit.
I picked up a s/h unit (60 thou miles ) from a scrappy for £100 , I took the chance and fitted it. It works a treat !!!

I was on cruches for a couple of weeks so that put the project back a bit.

When i drained the old unit the oil was burnt and there were a few bits of metal in it - possably shards of gear tooth. When the opertunity arises I will strip the TC for a better look.
At the moment I am back to work and useing the Jag every day, I've put about 1000 miles on the replacement unit and it seems ok.
I,ve also fitted a top-up system to the unit - it was much easier than I thought.
One slight concern I have is that there is no cooling duct to the TC - can anyone show me a picture of what it looks like so I can make one out of metal.
Thanks to everyone that have offered info and advise on the subject.
Rory

 

Here's pic from JEPC.

 

Rory, if you're making one of metal, the only caution I would offer is that as these scoops are near the lowest point they are often missing because they catch on something and being plastic, snap off. A metal one if too sturdy, might, in such circumstances, damage the sump/oil pan to which it's bolted. Soft ally might be your safest bet.