"Nanuuq" my Land Rover Discovery 2 diesel swap, ...forever a project!

[TheBigPurpleOne]

Hi Tinker, its Nick from the Cummins Land Rover Group on facebook!
I am enjoying following your build progress, just one query, do you think you may have effected the hardening of the FTC5090 output shaft or the prop yoke when you combined them to make your spud shaft?
Some of the early 6BT conversions on the facebook group used a home made spud shaft made in a similar way which later gave up due to splines stripping...
We now use brand new custom made billet 1 piece LT230 input gears to close couple the ZF S5-42 gearbox we get behind 6BTs to 1:1.003 Ratio LT230 transfer boxes, expensive but Aussie bush tough and well tested in the UK too.
Keep up the good work!

 

[Tinker]

Hi Tinker, its Nick from the Cummins Land Rover Group on facebook!
I am enjoying following your build progress, just one query, do you think you may have effected the hardening of the FTC5090 output shaft or the prop yoke when you combined them to make your spud shaft?
Some of the early 6BT conversions on the facebook group used a home made spud shaft made in a similar way which later gave up due to splines stripping...
We now use brand new custom made billet 1 piece LT230 input gears to close couple the ZF S5-42 gearbox we get behind 6BTs to 1:1.003 Ratio LT230 transfer boxes, expensive but Aussie bush tough and well tested in the UK too.
Keep up the good work!

Hello :)

I was careful to preheat & let it cool as slowly as possible. Partly due to the chromoly steel yoke's hardness, & partly to not obliterate the heat treat on the old output shaft. I'm sure it was affected to some degree, maybe could have had it annealed first, but no cracks developing along the welds has me confident the extra work on that was worth it.

But yeah I did entertain having a custom spud shaft made up. With the original 10-spline cut into the small end (for the transfer box) & then 35-spline cut into the big end to match that Strange Engineering yoke (sold for big Ford 9's). I thought it was a bit too much at roughly $600...

 

[TheBigPurpleOne]

Yea, the cheap method is definitely worth a try! If it does give up you have a back up plan. Im looking forward to watching the progress on youtube.

 

[Tinker]

That's what I was thinking, plus I could hardly turn down the chance to try my hand at some proper machining ...swear I didn't mean for that to be a pun... Anyway, yeah the progress will definitely ramp back up like I was doing back in the Autumn when I started. Bring on the spring! BRRRRR!

 

[adventure_is_necessary]

You might've noticed the big blue "X" ...which was a reminder to get around to fabricating a custom hatch to replace the window that matches up to my new cabinets on the driver's side. I ordered up a sheet of aluminum & an assortment of hardware to operate it.

Window had to come out, & the upper cabinet needed unbolting so I could access the backside:

Cut, welded, drilled, hinged, locked:

Mocking up after I had everything back in hand from my powdercoater. Sneaky OB emblem hiding under the masking tape:

Check out this quick clip (less than 2min) I hammered together of the build:

cont...

Was thinking about doing this on my rig just for the added access. Might even look at doing a similar cabinet build for my rig. Very impressed!

 

[JaimyMac630]

Wow! Great build!

 

[58-fc170]

Spring what spring?

That stub shaft turned out excellent.

 

[Tinker]

Spring just sprung right out the state!

Thanks, so glad I had the help of some skilled machinist friends with that one. Without exaggerating I can actually say it ended up perfect, the driveline shop tried to balance it & said they couldn't... because there's nothing to balance

 

[Dcwn.45]

Wow great build!
You have me wishing for a Cummings for my Tacoma!

 

[Tinker]

Well I got myself HUGELY distracted by a whole mess of stuff unrelated to the build (not an uncommon thing...) But now, thankfully, it's back at the top of my list & I'm still aiming to hit the road late spring. I'll try & get some of the latest work uploaded here tonight!

 

[Tinker]

Okay, time to tear into the transfer case! ...and now is the time to do it, anything I can do to save myself taking it back off the road once it's rolling.

So the common failure points in these Land Rover LT230 transfer boxes are: 1) The center differential spider gear pins & 2) the intermediate shaft's bore in the case.

The former is a relatively easy fix via Ashcroft's upgraded cross-pin that replaces the 2-piece pins that often fail during extended off road travel or long bouts of wheelspin. The latter is a much more in depth process requiring a complete tear down, then sending the case to a machinist where they'd cut a new bore & press in a special hardened support bushing. I was very relieved to find the intermediate shaft on my particular case was in great shape & won't likely need machining for a while!

First step was to pop off the hi/lo shifter turret, the detent plug+spring+ball, & the input housing to reveal the center differential:

Every bit of information I could find on accessing the diffs internals required near complete disassembly AND pulling off that giant taper bearing... but that would require resetting gear lash & replacing a few big difficult bearings. In my experience you can "sneak" out bolts like this from under the bearing in a series of steps much more easily. Taking a multi-day project down to a mere hour! Here you can see the bolts backed out until they bump the bearing:

Then it's just a simple as tapping the carrier to split it & lifting up the assembly. This allows you to unscrew them all again, & repeat:

In 5 consecutive unscrew+lift steps I was able to completely free the carrier half:

And now seeing those 2-piece pins in person... it's clear how easily these original notched pins can weaken enough when overheated to twist right in half:

It's a surprising place to skimp on steel when the all the other components here are so stout:

Comparison:

Back together!

Now to quit messing about & get the damn thing mounted! Weather's finally changing & the sun's shining in the shop... go time!

 

[58-fc170]

Smart route of disassembly on the gears.

 

[Tinker]

Smart route of disassembly on the gears.

Thanks man, really didn't want to tear the whole thing down for something so minor, my fingers were crossed so hard they were cramping on that one hahaha

Finally starting to catch up on my build videos too, aka EDITING TAKES FOREVER! / I'm slow...?

 

[BlairWhittle]

No worries! A single u-joint between is what I'll try 1st. And if I run into any vibrations that are too difficult to resolve then I ought to have just enough space for a CV/Double-cardan with the centering ball, like so:

I would warn against only using 1 joint, be it a U-joint or a CV joint such as this above GIF. Having only one joint between the TC and the gearbox would potentially transmit a lot more radial load to the TC input bearing. You see most divorced lt230 setups incorporating a shaft with a u-joint at each end and a slip yoke. This way the TC and the transmission are free to dance about as they please. I am referring to a setup such as this below:

It adds length to the setup but it just appears that you would be asking for trouble!

Anyway sorry to butt in, i just would not want this thing to fail, it is such an awesome build. I am pulling a lot of inspiration from it to do a om606 swap in my 2004 d2 here in Australia, i can dream! Keep it up mate, your build quality is top notch.

 

[bendts]

DUDE!

Nice job . Your camper build is what got me here. It's what i'd like to do in a DII Trailer I'm thinking of building.

 

[Archtop67]

Awesome Build Thread! you brought me to Overland Bound! I built my safari rack a few summers ago but im planning on a new build more substantial! and Being my Disco is an 03, I guess Im destine for a new locking transfer case lol

 

[genera_lee]

Sub'd for fab skills, good ideas, and 4bt goodness

 

[58-fc170]

Is it chugging along spewing the dark fog goodness yet?

 

[Tinker]

Is it chugging along spewing the dark fog goodness yet?

Nope, not there yet. Been having a "complicated" springtime. I have a monstrous amount of video footage that I need to edit too, here's hoping things will ease up so I can stay focused on it!

 

[dolli310]

Nope, not there yet. Been having a "complicated" springtime. I have a monstrous amount of video footage that I need to edit too, here's hoping things will ease up so I can stay focused on it!

Keep up the hard work. Can't wait to see her under her own power.