What's going on here then? Diff lock linkage on 200TDi fitted in a TD

I've realised what's been causing all my problems (broken CVs, clanky replacements, etc). Turns out the difflock was stuck on. And it has been since I had a replacement transfer box fitted, and probably before (and that was why the old box had so much wear).

Brief history:
- Bought Scratchy, loads of clonking in transmission, took it to a local knowledgeable chap who got it on ramp and said it's rear prop and t-fer box - go and see Mark at Crossways.
- Mark fitted the replacement t-fer box and prop for £200, which seemed to be a good price and 'specially good as I wanted it ready for a trip that weekend.
- Drove it around for a couple of weeks and then down to Brighton where the CV went in a major way. Garage there fitted a replacement (second hand) one that they assured me was okay and it seemed to be for a bit.
- Got back to Dorset and it was really clanking on lock. The local knowledgeable chap said that the replacement must be fecked, so I replaced it (and discs, callipers, pads, bearings and drive flanges) with new Bearmach kit.
- And then noticed that the NS one was clanking so did that as well.
- Then realised it was scrubbing on lock, checked and adjusted the tracking with a piece of string, still doing it. Took it down to the knowledgeable chap, he check it with his laaaserrrs and it was 100% spot on. Jacked it up and 'noticed' that the difflock was on. Tried to get it off with a screwdriver on the bottom of the linkage.
- I drove home, took the floor up, disconnected the linkage and moved the lever to disengage the difflock. Now, I can't attach the linkage with the difflock disengaged, it just don't fit - see photo.



So, what I think I'm going to do, is go and ask my mate to fab me a replacement bottom wire bit, with welded on washers, threads cut at the end and nylock nuts holding it in place. Should work?

Or am I missing somefing somewhere?

(Scratchy is an '87 110 truck cab, originally a TD now 200TDi (Disco), original (ish) gear and transfer box.

how come the bloke that fitted t/box didnt notice diff lock was on ?who wouldnt check by jacking a front wheel up ,when fitting another box the early linkage like that should work does diff lock work properly with a spanner on the nut ,lever that goes into slot in selector shaft can come out of slot and so not operate lock

jamesmartin said:

how come the bloke that fitted t/box didnt notice diff lock was on ?who wouldnt check by jacking a front wheel up

Click to expand...

I know, I know. Why he didn't check it was all working proper before it left. Why didn't I check. Why didn't the fella who fitted the replacement CV. Why didna the knowledgeable chap in town suggest it. Done now, money spent and I have got nice new shiny CVs, driveshaft and associated bits.

jamesmartin said:

,when fitting another box the early linkage like that should work does diff lock work properly with a spanner on the nut ,lever that goes into slot in selector shaft can come out of slot and so not operate lock

Click to expand...

Spanner on nut and it works fine. Jacked 'im up and comes in and out of diff lock fine. Problem is, the bottom wire bit of the linkage won't fit on the lever on the t-fer box with difflock disengaged, the upright lever fouls on the gearbox. The only solution I see is to fabricate a shorter (but improved) wire linkage bit.

Like I say, just wondering what I'm missing...

works liike that but there are several link rods making your own would be cheap answer ,on hi/low lever housing some have a restrictive gate plate under gaiter it can be removed or hole made bigger to give more lever movement ,is pear shaped plate fitted right it is on a slot so shouldnt really fit wrong but ,it seems quite far over towards box if that were it needs to be to release lock 90 degrees is more usual,it will move further than is necessary to release or put in lock

I found when my diff lock was not working correctly that the slot in the cam arm on the top of the front output was worn allowing too much movement on its shaft.Worth a quick check.[like yours would work with spanner]

There's not a lot of movement in the shaft and clicks in and out quite definitely with a spanner, it's the linkage fouling on the gearbox housing that's stopped it disengaging the diff lock.

By my reckoning the pear shaped bit is 90 degrees out, but I can't work how to adjust that, it seems like you can only turn it 180 which wouldn't work at all. I'll go have another look before I get Lee to make me a new linkage bit...

yes it only fits properly one way ,migth be worth undoing the 3 bolts hold the housing in and check its sitting in selector shaft correctly

jamesmartin said:

yes it only fits properly one way ,migth be worth undoing the 3 bolts hold the housing in and check its sitting in selector shaft correctly

Click to expand...

Yep, been there and done that. I was going to take it offed again when I've finished my coffee and see if the bottom part of that mechanism is adjustable (not, if I recall right)... If only I could turn it 90...

Well, it dun't seem to be. So my mate shortened that bottom part of the linkage by 15mm...

Now the geometry is all wrong and although it connects it doesn't engage or disengage effectively (read at-all). Going to take it back to the chap who fitted the t-fer box in the morning and see what he makes of it...

did you remove 3 bolt housing and see slot in selector shaft ,you can work it wit a screw driver to prove it operates ,it is possible for the lever that sits in this slot to ride over the shaft ,espeially if bent a little or if switch is wound in too far etc,pear shaped lever on top should point directly forward and be out of diff lock ,but may need to travel a little further to work as the dif lock is spring operated and not direct