A resurgence in 4x4s

[Philip Chidlow]

I've noticed the BX 4x4 is making an appearance here and there. It's a pleasant surprise to me as a year ago the 4x4 was to all intents and purposes 'written off' by all but a small fringe group of nutters ( ).

The achilles heels of the 4x4 is well documented: the toffee-like splines - and the exhaust made from 100% unobtainium. On the former there was a hint somewhere that somebody was contemplating remanufacturing parts of the transmission to make it up to the job...

What came of this plan? Anyone here know?

Also someone had a complete 4x4 hatch exhaust which was I believe offered up to be lent out as a pattern for S/S fabrication...?

[citroen7]

i believe it was ian fern that had the exhaust my 4x4 has a bespoke stainless steel system and lies sleeping in the garage ,funds could well be available this summer to recomission the beast!
if you go on to vannys BXC you should find out more although i have tried to register several times and have not been sucessfull

[philhod]

I spend most time on BXP and I still have Brian kings g/box in bitz.
I have determined a solution to the problem. I have the 2 offending parts joined together in a machining jig waiting to be machined.
Unfortunately, since I retired I cant use the college's machine shop,(insurance H&S) and most of my old companies want money.
So! If anyone knows where there is a conventional milling machine knocking about with an 8 mill dia/ceramic slot drill, please let me know.
Alternatively I have made a detailed drawing if you know anyone who would do it. All told it's only about 3 hrs work

[Philip Chidlow]

Wow. Someone help?

[philhod]

For anyone interested Phil, the solution, is to use the splines purely for alignment purposes, then machine 3 keyways through the outer sleeve and into the inner sleeve, but not through it.
Once done, make 3 keys to fit from moly van (which I have)
Then weld these to position using TIG . The drive will then be from the 3 keys rather than those rather insignificant splines.
Finally turn and grind excess material back to original dia so the center bearing in the transfer box will still fit.
As I said, I have made a drawing and have all the dimensions.

If this works and I see no reason why it shouldn't, it will be a relatively inexpensive repair for many 4x4's sitting waiting.

The actual design of the box is quite clever, having one of the front driveshafts run through the center of the transfer box to the diff ( thats why the keys cannot protrude inside) it's just that they assumed the center bearing would not allow any movement and therefore 2mm splines would be ok. But, once any slight wear appears in this the splines soon wear. The one I have has lost 1/2 of it's height and there is only perceptable movement in the bearing.

[4B4]

I've noticed the BX 4x4 is making an appearance here and there. It's a pleasant surprise to me as a year ago the 4x4 was to all intents and purposes 'written off' by all but a small fringe group of nutters ( ).

The achilles heels of the 4x4 is well documented: the toffee-like splines - and the exhaust made from 100% unobtainium. On the former there was a hint somewhere that somebody was contemplating remanufacturing parts of the transmission to make it up to the job...

What came of this plan? Anyone here know?

Also someone had a complete 4x4 hatch exhaust which was I believe offered up to be lent out as a pattern for S/S fabrication...?

There is a blue one just appeared on Ebay.
http://cgi.ebay.co.uk/CITROEN-BX-gti-4w ... 3cb8f1ef3c

[djm666]

I had one made by goughs. they did a superb job.
i did hunt to the end of the earth for a new steel front pipe for the pattern. but if you are keen you can find them.
and i had new parts remanufactured for the gearbox, but you have to be keen as it costs lots.
i now have to strip the new one i bought as the clutch is slipping, so it will be getting a full overhaul.

[philhod]

To have new parts made is beyond the means of most people today. That is why I came up with the previously described modifications.

If I was doing this commercially I would be looking at around £35 for materials and consumables. About £80 for mc/ing and similar for the strip and re build of the diff and transfer box.

I think a permanent solution to the problem for under £200 represents good value.
It could go to £250 as I'm a bit out of touch on costs since I retired.

[assembled]

Greetings from Lithuania!

philhod, would it be possible to get a copy of the drawing of the shaft modification? I am an owner of a 4x4 with splineless shaft and would really like to do something about it. I have found a company that could restore the splines, but if you say that it would not hold, then I will eventually end up at the same place. Previously you mentioned that the splines get worn because of loose bearing. I had an idea that it happens due to water and dirt coming to the uncovered and non lubricated spline joint and hoped that if I would grease it with appropriate grease and seal the gap between gearbox and transfer box the problem would be solved.
Any opinions on that?

[Vanny]

Philhod doesn't frequent this forum too often, he's usually found on the BXProject. I've sent him a message to let him know your after some assistance.

[philhod]

Hi.
I have now got access to the machine shop as the person stopping me has himself retired.
The parts and drawing are there now and one of the final year apprentices is going to do the job.
Once the M/cng is done I will weld the keys myself as the staff in the welding shop are not sufficiently skilled at TIG..
I am working again afternoons but will try to get the drawing back and scan it.
That should allow me to attach it to email?

On second thoughts my copy has all my calculations all over it. I'll see if I can get into the CAD room and make a fair copy.

As a point of interest. These splines are not in a position where they can get contaminated. They are designed as a very close fit allowing no lateral movement and therefore, technically, no wear. If they had just made them deeper say 3/4 mil instead of 2, there would never have been a problem. The brg that suppounds them is in the centre of the transfer box and is well lubricated and to be fair the movement in it is barely perceptable. That is the point for with that design there has to be none at all.
This type of repair will make any slight looseness in the brg irrelevant.