D21 clutch/gearbox issue.. Needing help or ideas please!!..

[ThaJFactor]

Hey fellow Navara-ers!!.. Long time lurker, first time poster here, but I'll get straight to the nitty gritty..

Not too long ago I picked myself up a 1994 D21 Navara TD27.. When I purchased it, it had a bit of a noisy gearbox which I thought was clutch.. Over the space of a week, the dodgy "clutch" issue turned in to me losing gears 1-4 and only left with 5th and a grinding/whining reverse.. I discovered this after going through all gears just fine, sitting in 5th on the highway at 100km for roughly 10km then downshifting to take a roundabout to find I had nothing..

Time to pull the box and transfer case out.. I did this with no problems (removal wise) and fitted a new clutch and pressure plate.. The old one looked semi ok, but changed for a new one all the same.. Spigot and throwout bearings were done at the same time.. I knew the box had a small oil leak from the front of the bellhousing so I removed the cover the change the input shaft oil seal and found that the bearing was toast and the input shaft was semi chewed out on it's gear..

Instead of mucking around with rebuilding the old box (time and money), I sourced a replacement from a wrecker.. I pulled the gearbox and transfer case out of a 89 Pathfinder with a Z24(?) and changed the bellhousings over (which is something I noted was required).. The gearbox out of this car was known good as I drove the Pathy to where I pulled the box out..

Anyway, I have since got it all back in today but have the dilemma of having no gears at all.. Engine running I can change through every gear with the clutch pedal in or out.. It doesn't make a difference and the Nav just does not move.. I can have it sitting in gear (any gear), clutch out and it feels like neutral.. The clutch pedal has a good feel to it and the fork is moving..

I'm stuffed as to what I should look at next though.. Box and clutch setup replaced but no change (infact worse).. What am I missing??.. Would there be anything I have done that is making the clutch not engage properly??..

Any help or ideas would be greatly appreciated!!.. Thanks in advance..

 

[Dion]

Just a quick check... the transfer case is in gear, right? Make sure if you've changed the linkages around that what you think is 2H in the transfer, is indeed 2H and not N.

 

[ThaJFactor]

Just a quick check... the transfer case is in gear, right? Make sure if you've changed the linkages around that what you think is 2H in the transfer, is indeed 2H and not N.

Thanks for the reply Dion.. I didn't remove the linkage from either box so I'd be saying it's still OK.. I've tried in 2H, 4H and 4L (with hubs locked obviously) but no go.. It's almost like the old box was, but no gears at all now..

Just a random thought, but the fork and bearing in the "new" box are visually different to the old box, but seemed to fit the same.. When I reinstalled the new box, I used the fork and bearing from the old box (new bearing) in the old bellhousing.. Could that be a problem??..

 

[Dion]

I've tried in 2H, 4H and 4L (with hubs locked obviously) but no go..

Just FYI, it doesn't have a centre diff. That means two things, firstly hubs don't need to be locked for you to be able to move in 4H and 4L, it will still drive through the rear. Secondly, never drive it on tarmac in 4x4 with the hubs locked.

Just a random thought, but the fork and bearing in the "new" box are visually different to the old box, but seemed to fit the same.. When I reinstalled the new box, I used the fork and bearing from the old box (new bearing) in the old bellhousing.. Could that be a problem??..

So if I follow correctly, old bellhousing, old fork, replacement bearing? Shouldn't cause any issue. It does sound like the clutch is still not engaging when the slave is at rest position. Is there play in the fork with the clutch "out"?

 

[Stelianos]

there is nothing wrong driving in 2H with front hubs locked, d22's in europe come with fixed hubs which means unless you upgrade yourself, the front diff wheel, propshaft etc etc rotate, wear and maybe rob you some power. i had fixed hubs myself until i went for manual ones last year. i like how it drived with the hub on UNlock but i also miss the nice feeling of just going from 2H to 4H and 4L whenever i feel like it.

 

[ThaJFactor]

So if I follow correctly, old bellhousing, old fork, replacement bearing? Shouldn't cause any issue. It does sound like the clutch is still not engaging when the slave is at rest position. Is there play in the fork with the clutch "out"?

Correct, but to clarify, the new bearing is for the old box.. No play at all.. Ultra tight if anything

I got a mechanic to look over it yesterday and apparently it needs to use the fork and bearing from the petrol bellhousing.. I don't know exactly what he did for testing as I was working 200km away, but apparently he had gears engaging..

 

[Dion]

I got a mechanic to look over it yesterday and apparently it needs to use the fork and bearing from the petrol bellhousing.. I don't know exactly what he did for testing as I was working 200km away, but apparently he had gears engaging..

Sounds like a resolution? Must be a difference in the input shafts...?

 

[ThaJFactor]

Sounds like a resolution? Must be a difference in the input shafts...?

I'm going to pull it back out on Monday so I'll be sure to update on how that goes..

It was tested by popping the fork off the pivot pin, which released any pressure.. I tired today myself and sure enough it jerked when starting in gear, clutch out..

RE the input shaft length, I was under the impression they were all the same in the same model, apart from bellhousing??.. An oversight on my behalf probably!!..

 

[Dion]

RE the input shaft length, I was under the impression they were all the same in the same model, apart from bellhousing??.. An oversight on my behalf probably!!..

I was under the same impression so it'll be interesting to see what you discover. I can see from the microfiche that the throwout assembly is quite different between the two, but the only part you've brought in from the donor is the input shaft. Unless something is in backwards

 

[ThaJFactor]

I was under the same impression so it'll be interesting to see what you discover. I can see from the microfiche that the throwout assembly is quite different between the two, but the only part you've brought in from the donor is the input shaft. Unless something is in backwards

Yep, the throwout assy is completely different.. The bearing assy is fatter and the fork is a little different in size.. Possibly length too..

Not too sure what would be in backwards, but I'll be looking again for sure..

When I first did the clutch replacement and put the old box back in it worked just as it did before replacement (1-4 dead, 5th&R working) so it would be safe to say that part of proceedings is fine??..

I'm just trying to dot the I's and cross T's here haha!!..

 

[D21-DX2.7D]

I tend to agree it appears to be a input issue due to different part sizes from petrol gearbox and the diesel box. The fact it runs and doesn't stall implies to me it's got nothing to do with engine side of things.

 

[ThaJFactor]

Well I went for it all day on this and had a win, although its a weird one to me..

Started the day with the setup it was left with (Diesel Bellhousing, fork, t/o bearing and clutch/pressure plate.. "Petrol" box) and went to do the simple fork change.. In with the "petrol" fork and bearing, and all fitted up nicely.. Due to the bearing fatness difference, the box didn't really bolt up happily so back it came again..

Back in with the diesel fork and bearing to go back to the same problem as before.. Needing this ute back on the road, I decided to do a bit of modification to the clutch slave pin, knowing I had a spare available, and to see what would happen.. I took about half the length off the pin (gradually until the length was right) and reinstalled it.. Perfect clutch all round..

So from doing this, everything is working 100% fine.. 4X4 in H & L and 2WD and if anything, the old girl seems to have a bit more get up and go..

At the end of the day, it is a bandaid fix, but I can only think I have the wrong clutch and pressure plate in.. Should I be using one for the petrol model instead??.. I'm happy to leave it as is if it isn't going to cause any further damage, but I do want to get to the bottom of it..