Dave’s long-term Lil’Bugga Buggy Build

Ah, sigh of relief, The Boogie buggy build is coming to an end, and I plan on driving it as much as I can over the summer months...

I’ve really enjoyed building it, and it’s kept me safe and sane over the (winter) COVID lockdown... I’m super happy with it, it’s ideal for greenlaning, and has a windscreen and vinyl soft-top roof to keep me dry on rainy days... And it still resembles a Jimny, which was needed for MOT, insurance and road legality purposes...

BUT... I still long for a tubular roll-caged / framed single seater buggy, so in March I messaged our mate James Priestley (who breaks the odd Jimny) and gave him a list of what I was after..

In early April James messaged me back to say he had most of it amassed! Ummm, so in mid-April when lockdown restrictions allowed I went up and loaded the NGeeVee with bits! -

 

Two front axle casings / hubs
Two front diffs
One pair of (both) short front shafts (?!)
Four front radius arms
Two sets of steering bars
Two power steering boxes
One power steering pump
One power steering reservoir tank
Four alloy wheels
A pair of JimnyBits HD panhard rods

Hmmm...

Yes, starting in the winter, I’m going to attempt to start building a four wheel drive, four wheel steer, four wheel disk braked (fiddle brakes then.) off-road-only buggy... just for the fun and challenge of building it, and possibly the odd AWDC competition, if and when it gets finished...

Progress will be slow, no rush, take my time and potter when I have spare time, so probably over the next few years / winters...

I’ve also picked up a reverse (starter) motor kit, as it will undoubtedly be bike engine based...


 

so it will be drilled thus -

 

to fit on the intermediary prop between the bike engine and the rocklobster transfer box I also have sat around...

And then these arrived...

 

Four standard front springs, four looong shocks from Russ at JimnyBits, spring clamps for dislocating springs, and panhard rod bushes.. to be fitted once the panhard rods have been shortened and rewelded (?)... Ah, yes, I forgot that bit hence the short side shafts... the axle tubes are going to have 12” cut out of them to make a smaller, narrower buggy, and using two front axles will make the length shorter too...

 So the parts are sat at the back of my garage waiting for a start in probably September... but my crazy min is working overtime!!!

This is going to be fun!

Bring it on 

Small  update...

When I went up to James Priestley's to pick up a replacement gearbox for the Boogie, I also came back with -

 

A burgundy (not for long!) bonnet (s it will be cut down to scale for the lil'bugga), and a pedal box assembly...

At the start of our latest greenlaning trip Riccy gave me an additional short front shaft in some kind of deal with James, and lent me a long shaft to have a look at and a measure -

 

So at the top, a long shaft to measure to work out the difference between it and a short one, as that's how much will need removing from the two front axle tubes... The two short sided standard 22 spline shafts for the front front axle And at the bottom two TrailGear 26 spline HD short shafts  and HD CVs for the rear front axle... :lol:

During a WhatsApp conversation with Riccy he pointed out that the rear front axle will turn the wrong way... (and try and tear the lil'bugga apart!) I'd thought about if for a while in the shop, weirdly twirling my fingers trying to work out the rotation of the  props, etc. and thought it would work! :lol: But no worries -



Referencing this old photo from the Boogie build thread, you can see that a Jimny's front diff is high-pinnion, the pinnion is at the top where the prop enters the back of the diff, so I'm hoping I should just be able to flip the diff over, make it low pinnion (more oil for the pinnion!) and that will make the rotation right...

Andy "Baloo" has pointed out on his Lightwight Buggy Build Thread that if you narrow a front axle -

 

There's not much width left / no turning circle... but look at those MAHOOSIVE tyres! :woohoo: , I'm only planning on going for 215/80-15 Special Track tyres, as it's a small buggy, so everything is to a matching small scale, hence "lil'Bugga" !

We'll see, when things start in the autumn / winter... 

Hi Dave.

I have followed your Buggy build with considerable interest and awe. I don't think I would have lasted more than half way before giving up.

The idea of building Little Buggy with 4 wheel steer will give you an amazing turning circle but as has been pointed out you will have trouble with diff. rotation, so I have a few points to consider.

If you turn the diff round to give a low pinion set-up you will/may have the problem of the crown wheel hitting the wall of the diff. housing. This is the part that has the filler plug. You can overcome this by, knocking out the indent, or cutting the whole back plate off and turning 180 deg. and relocating the filler plug.

Or,

Keep the rear diff casing as is and grafting on the hubs from the front axle.

First idea is probably the easiest with the last the hardest. It's all about getting the alignment right.

Roger

THANKS very much Roger! I'll look out for that when I get to that part...

Cheers! Foresight is a wonderful thing!

I wasn't doubting you Roger, I was inquisitive... 

 

Indeed, a front diff does look symetrical...

 

This is the diff installed  in the casing the right way round, "high pinnion" (Pinnion at the top)

 

I slotted the axle casing to allow for the clearance for the crown wheel to fit with the diff flipped...

And indeed, it doesn't fit...

 

As Roger indicated, to flip the diff I'd also have to flip the "front cover"... as it's shaped to suit...

That's probably easier than cutting both axle tubes off the diff pumpkin and flipping the diff with the casing though? As that would mean moving the diff drain plug as well... Hmmm, have to sleep on that one... I do have another front axle casing hanging around the garage though, I could just cut the diff drain plug out of it and graft it in after flipping the whole diff and it's pumpkin... the axle tubes will be re-welded to the pumpkin with braces fitted anyway, so that might be easier than cutting and welding the front cover then? And tidier...

 

From the inside...

THANKS Roger... food for thought!

Fortunately, the stud holes appear to line up.

Roger

I still think just spinning the diff round wont help the direction it rotates im afraid.

Is it possible to interchange the ring and pinion gears to those of a rear one, which would sort it out and possibly let you keep the high pinion casing?

I would be tempted to just use a rear diff in the front casing you shorten for the back. I know it wont have high pinion, but it will go the right direction and you can still have the rear steering...

Yes it will.
The pinion remains where it is and the crown wheel changes sides.
If the pinion rotates clockwise and the crown wheel is on it's left the shafts are in reverse. Crown wheel on the right and shafts turn forward.

Roger

 

During a WhatsApp conversation with Riccy he pointed out that the rear front axle will turn the wrong way... (and try and tear the lil'bugga apart!) I'd thought about if for a while in the shop, weirdly twirling my fingers trying to work out the rotation of the  props, etc. and thought it would work!  But no worries -


are you sure that is correct ?

if you put your head where the transfer box out put is and look forward the front prop turns anticlockwise to move the vehicle forward ?
now  move that diff to the rear and look backwards at it   the prop now needs to turn clockwise to move the vehicle forwards ?  which is how the props rotate as they leave the transfer box >  so by turning the diff through 180 deg to fit in the rear the drive is maintained in the right direction ?

i will need to fiddle with an axle to confirm or deny  that lol  

 

this seems to suggest a rear fits in the front ?

rear diff to front? - BigJimny Forum