Rebuilt gearbox

boguing said:

Now it's in I'd just do 500 or so miles, see how it goes. If it doesn't ease up then strip and rebuild, testing it at every stage.

The parts book that I have shows that the only difference in selectors shafts and forks for suffix A and B is the reverse one, others unchanged.

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Ah, no I mean’t the selector hub. There’s different versions for suffix A etc. I’ve come this far, I’ll just press on and see if a few 100 miles helps, cheers

steve2286w said:

There was changes in parts in the main gearbox not sure if any of this applies , but what new metal bits did you buy

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New first, second and synchro hub. All quoted as being the right numbers for a suffix A, but maybe they weren’t.

The synchro is described as “TAS made in Italy”

Not sure what make that is, but maybe it’s ****e?

A bit late, but for the benefit of anyone else reading, throw away those old stock rubber seals that go under the right angled covers for the ball springs. They're rubbish - I had bad leaks from mine after just a few miles. Get some fresh 19mm heater hose, cut 4mm slices and it works perfectly.

Next time I do one I'll find alternatives for all the shaft seals too.

Well, it’s as bad when driving..

It’s a pig of a vehicle..!! So fecking annoying.

So, new selector hub needed, I think… well why not, I don’t need £240 do I..

What I do find is that when selecting 2nd, if I pull the gearstick fully, it seems to overshoot after engaging the gear, and I get a slight grinding of gears… trying to visualise, and the only thing I can think is that reverse is touching the selector hub teeth… so the rod is not connected to the fork in the right place, or the reverse idler is I the wrong place… might try adjusting the selector forks one last time, then it’s coming out again… might wait for winter!!!

So, found the issue. The selector hub is an Italian made item, from a reputable supplier, however on strip down and comparing to the new old stock one, the machining can be seen to be too “deep”, and maybe too shallow. On the bench, I can replicate the teeth on the gears not engaging, and actually sitting and locking into the machined grooves… might be of use to someone, so just reporting back.

NOS item

If you have the wrong gear sets in from a different suffix you will know right away, trust me on this from experience.

Hello, here’s the next instalment of the nightmare that is my gearbox rebuild!

So, all going well, ‘box back in. Start her up, and can select 1 to 4 just fine… however, reverse is not possible!!

On the bench reverse was selectable. The idler slipped nicely across meshing with the selector hub and the Layshaft, and rotated as it should.

So, top off, and selectors forks etc out. The reverse idler now clashes with the selector hub and won’t engage… but if I turn the hub and main shaft a quarter turn, it slides in. Seems the hub is either oval, or the machining isn’t good. It’s NOS from Blanchards but there were some edges on the inner that i had to file away.. didn’t really consider the outer tbh. I think it only just doesn’t engage, so I was going to engage reverse manually where it can, and fix it in place with the lid on. Then start and run it in reverse for a bit, with the props disconnected… bad idea, or could it “wear” it enough to allow selection… can’t face taking it all out again! But I also don’t want to wreck it…

I think it was mentioned earlier in thread about swppaping bits around and if they are compatible
this popped up as a similar one to yours


@BruceB must know a bit about this topic when he was working on his last year

edit oh I see he replied just earlier

Thanks for the reply Steve. So, I did what I suggested I was going to do. Fixed it in reverse, jacked up the rear and ran it in reverse for a bit, moving the selector in and out slightly. No bad noises or anything and now the reverse idler gear “just” engages, every time. So, fingers crossed it’s sorted…

As for mixing up bits from different prefix ‘boxes, what I’ve bought are all sourced as A. Whether what I received was correct was debatable. 1/2 selector was a TAS unit made in Italy from AP Land Rovers. Utter crap. I am wondered about the lay gear now, and the reverse issue I had/have. It did seem to be the same as the old one…..

The NOS 1st, 2Nd and selector hub from Blanchard seem to be good. I do have spare 1st and 2nd gears now, which should be fine, so if anyone want to buy them cheap, let me know. In fact I have a pile of A Gearbox parts, which are mostly ok, except for broken 3rd and the original 1/2 selector hub.

Some good original stuff from Blanchards, when I was last in there was chat of them not closing but a bit hush hush so don’t tell anybody.
glad you got it sorted maybe run it for a few hundred miles and see what g/b oil looks like and if ok reuse after filtering any little metal bits if any
good luck keep us posted

I have moved on from the gearbox build and as usual, at the end of the gearbox build i was a confitmed expert and could identify every part, 6 months later i have pretty much forgot it all and would need someone to point out what a gearbox looks like. i did take pictures and list my own errors in my build thread
Couple of points though . Is it the selector that is not engaging on top or the reverse gear itself? The selector arm engages directly onto the gear and i cant see how this would not slide the gear along the shaft unless the selector mech on the top was not allowing engagement. You should be able to just take off the top covers and slide the reverse gear in and out?

BruceB said:

I have moved on from the gearbox build and as usual, at the end of the gearbox build i was a confitmed expert and could identify every part, 6 months later i have pretty much forgot it all and would need someone to point out what a gearbox looks like. i did take pictures and list my own errors in my build thread
Couple of points though . Is it the selector that is not engaging on top or the reverse gear itself? The selector arm engages directly onto the gear and i cant see how this would not slide the gear along the shaft unless the selector mech on the top was not allowing engagement. You should be able to just take off the top covers and slide the reverse gear in and out?

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Ha, I’m looking forward to forgetting tbh! End up dreaming about the bloody thing…

The reverse gear does slide, with the selector arm removed etc, and engaged just fine, but only when the 1st/2nd selector hub was in a certain position.. when the main shaft is turned say 180degrees the idler wouldn’t then slide and engage, but get stuck, and not mesh. Like the hub was not perfectly round, or edges of the teeth remaining. It seems better now, after running it engaged for a while. So fingers crossed I won’t need to take it back out!! Cheers

All I can say is good luck.

Nope, it’s just ****e. Drove to Belvoir Castle, and I’m surprised i got back. Good news is the steering, brakes and cooling (even in the heat of yesterday) are great now. Bad news is the 1/2 gear selection is still tight… but worst news is that 3/4 are a fricking nightmare. All ok from cold, changing up. Once fully warm/hot, crunchy time. Double clutching works to an extent, but very tricky to not crunch. Going down the gears… forget it.
The 3/4 selector is a bearmach one, brand new. The right one for an A suffix. It’s like the gear is being selected before the balkring has grabbed the gear, which might be the springs being rather weak. The unit did feel quite easy to slide when building the ‘box. Which is the opposite of the 1/2 selector issue i have now… getting decent parts seems to be nigh on impossible. So, that’s winter sorted… out it comes.

Another issue I had was what I think was vapour lock or fuel starvation. High revs in a gear, and or climbing a hill, the engine was kangarooing a bit, so had to drop the revs, but then struggled to keep momentum, then changing down (see above… so that was fun!) until I’m going slower and slower. I have a Weber carb and standard pump. It’s is its first proper run for maybe a decade I’d think, and it was super hot weather. The fuel filter does appear to be empty but that not unusual, and pumping the primer does seem to send fuel. I’ll check for leaks in the pump,
plus I do have an SU to fit anyway. The tank might have crap in the pick up too, so when more fuel needed, it can’t deliver… Might consider an electric pump instead, away from the hot engine.

That said all that, I really like the old truck! Persistence is key… right?

Has anyone experience of Liqui Moly gearbox additive? Someone’s suggested it to help a newly built gearbox with lower tolerances used. Could it do any harm in this gearbox?

DeviousLandyGod said:

Has anyone experience of Liqui Moly gearbox additive? Someone’s suggested it to help a newly built gearbox with lower tolerances used. Could it do any harm in this gearbox?

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I wouldn't use it to start with. The first lot is going to get loaded with all the crud from running in and you'll be ditching it.

Next is what you're going to use it for. I went for decent Millers because I was going to do a few hundred miles of maximum load tows each year, and that does get the box hot. For light use I'm not sure I'd use anything particularly expensive - it's not like the LT77 in a Defender that changes better with ATF than normal gear oil, a Series box is pretty loose right from the start (umm, normally!)

ps. Epoxy a magnet into the hollow drain plug, no idea why LR didn't fit one.

As far as I'm aware the tolerances haven't changed, if it's rebuilt with new parts then it should be as it left the factory