I know this is the Defender bit, but I have a Series question...

[Junglie]

...and don't want to just jump in there unannounced. Plus I know several folk in here have significant experience of both types of pain Land Rover.

My neighbour has just bought a very late Series 3 109 with a 300Tdi conversion. It's got some work needed, but it's nice. But...

The gearbox sounds horrendous - like every bearing and meshing surface is dry - until you put it into 4th, when it' sounds about right. Could it be as simple as low oil i the box and 4th is on a lower shaft which is still getting lubed? 

It looks like it'll need a bulkhead at least. Be good if it doesn't need a new box too. It's got Fairey O/D and FWH which always used to be considered the mutt's nuts when I was a yoof.Is that still the case?

Cheers.

[Bowie69]

4th is straight through, so if noisy it will be the layshaft, if there's no oil in it won't sound great either! 

That said, a series box is never really quite IMHO.... 

[Snagger]

Yep, fourth is just the synchro hub sliding forward and directly coupling the input pinion and the main shaft, so the lay shaft is bypassed.  The lay shaft will still be rotated by the input pinion, but all three output gears on the main shaft will be free spinning, so there will be no load on the lay shaft.  It might just need new bearings if it is bad in 1,2 and 3 (and probably reverse, as that goes through the lay shaft, the reverse idler and the 1-2 synchro unit in its neutral position).  The lay shaft rear bearing is especially small and under-specced.  It is also not that uncommon for the bolt (SIII) or nut (SII) on the front end of the lay shaft to come loose and allow the shaft excessive end float.  Any issue with the lay shaft needs a full strip down.

He can remove the top of the gear box and the selector shafts and forks to have a bit of a look inside.  Visibility isn’t fantastic, but it would allow a very good look with a boroscope.

[Junglie]

3 hours ago, Snagger said:

Yep, fourth is just the synchro hub sliding forward and directly coupling the input pinion and the main shaft, so the lay shaft is bypassed.  The lay shaft will still be rotated by the input pinion, but all three output gears on the main shaft will be free spinning, so there will be no load on the lay shaft.  It might just need new bearings if it is bad in 1,2 and 3 (and probably reverse, as that goes through the lay shaft, the reverse idler and the 1-2 synchro unit in its neutral position).  The lay shaft rear bearing is especially small and under-specced.  It is also not that uncommon for the bolt (SIII) or nut (SII) on the front end of the lay shaft to come loose and allow the shaft excessive end float.  Any issue with the lay shaft needs a full strip down.

He can remove the top of the gear box and the selector shafts and forks to have a bit of a look inside.  Visibility isn’t fantastic, but it would allow a very good look with a boroscope.

And that sounds like a diagnosis! 1,2,3 and R are all noisy. I mean crazy noisy. 4 is noisy, but just Landy noisy.

Thanks

[Bowie69]

If they are that noisy, suggest driving it is only going to cause more problems and breakages, time to pull it out I'm afraid.

[Junglie]

2 hours ago, Bowie69 said:

If they are that noisy, suggest driving it is only going to cause more problems and breakages, time to pull it out I'm afraid.

Yep, that's the plan - it's going to need a bulkhead anyway so it will all happen at once. Guessing that a 300TDi engine on an unmodified Series 3 box is going to be a strain anyway?

[Bowie69]

Probably fine,  but as it is a 109 you could consider doing the right thing and stick one of the later gearboxes in...

[smallfry]

I have run several V8s through series boxes and Fairey overdrives with no problems that I can recall, except for "normal" howling.

In a 109 though, loads of room for a later and better gearbox for the job

[Bowie69]

Even a auto 

[Junglie]

1 hour ago, Bowie69 said:

Even a auto 

Get thee behind me!

[Junglie]

2 hours ago, smallfry said:

I have run several V8s through series boxes and Fairey overdrives with no problems that I can recall, except for "normal" howling.

In a 109 though, loads of room for a later and better gearbox for the job

Shame. I was hoping to sell him my 12J with a clear conscience...

[Junglie]

2 hours ago, Bowie69 said:

Probably fine,  but as it is a 109 you could consider doing the right thing and stick one of the later gearboxes in...

Actually... could we just drop an LT77 into it and keep everything else? Or is it not quite that straightforward?

[Chicken Drumstick]

25 minutes ago, Junglie said:

Actually... could we just drop an LT77 into it and keep everything else? Or is it not quite that straightforward?

Yes and no. As far as gearbox swaps go it is probably pretty easy. But there is still quite a bit to sort. 
 

Assume you’d also maybe look at an Lt230 swap? 
 

Levers and mounts will all be in different places. Obviously you’ll need to sort the clutch out. Slave cylinder and physical clutch. Not sure if you’d need a bell housing too. Lt230 is awd, there are lots to make it 2wd or maybe keep as is. And then sort a rear prop out and maybe some stuff with the handbrake. 
 

Overall should be bad as a swap and lots of factory bits that can be used. But it won’t be a direct 1:1 swap. 
 

Personally I’d also want to weigh up what is wanted from the vehicle. For me a big part of a Series is character. A lot of that comes from the gearbox and your interaction with it. There is just something about a 4 speeder and the Series box has IMO a nicer “snick” gear change than the 5 speed boxes. 
 

Also in an engine and gearbox swapped 109 you start to question if buying a 110 would have been a whole heap simpler!

[Snagger]

A good SIII box will handle a Tdi, but it needs a degree of mechanical sympathy.  Anyone who drives with binary feet will break it soon enough, but then again, that is true of those boxes even behind a 10J.  They also benefit from having an overdrive rather than 3.54 diffs so that the overdrive can be used as fifth gear and the hard pulling or acceleration done in the lower gears with standard final drive ratios reducing the output resistance and torsional wind up.

[Junglie]

On 7/5/2024 at 2:56 PM, Chicken Drumstick said:

Yes and no. As far as gearbox swaps go it is probably pretty easy. But there is still quite a bit to sort. 
 

Assume you’d also maybe look at an Lt230 swap? 
 

Levers and mounts will all be in different places. Obviously you’ll need to sort the clutch out. Slave cylinder and physical clutch. Not sure if you’d need a bell housing too. Lt230 is awd, there are lots to make it 2wd or maybe keep as is. And then sort a rear prop out and maybe some stuff with the handbrake. 
 

Overall should be bad as a swap and lots of factory bits that can be used. But it won’t be a direct 1:1 swap. 
 

Personally I’d also want to weigh up what is wanted from the vehicle. For me a big part of a Series is character. A lot of that comes from the gearbox and your interaction with it. There is just something about a 4 speeder and the Series box has IMO a nicer “snick” gear change than the 5 speed boxes. 
 

Also in an engine and gearbox swapped 109 you start to question if buying a 110 would have been a whole heap simpler!

We have to rebuild the gearbox(es) anyway, so I think we'll probably run with what we've got. It already has a swapped engine (which I'm not sure is good or not, though it will be hauling heavy loads as it'll be full of beer (!) so it might just need the extra oomph.)

And you're right about the character. But a Series is so much prettier than a 110 as well - that recessed front grille just does it for me - and as it's going to be used as a promotion tool (mobile bar for a London micro-brewery) the aesthetics are important...

[Junglie]

On 7/6/2024 at 3:56 AM, Snagger said:

A good SIII box will handle a Tdi, but it needs a degree of mechanical sympathy.  Anyone who drives with binary feet will break it soon enough, but then again, that is true of those boxes even behind a 10J.  They also benefit from having an overdrive rather than 3.54 diffs so that the overdrive can be used as fifth gear and the hard pulling or acceleration done in the lower gears with standard final drive ratios reducing the output resistance and torsional wind up.

Well as we have overdrive already it looks like we're onto a winner