LocostBuilders - powered by XMB

3.14 open diff to lsd

Johneturbo - 6/10/11 at 02:08 PM

Just been thinking of my next winter upgrades as the car is now sorn'd

I'm currently running a 7" 3.62lsd and i have a 7" 3.14 open diff in the garage so i'd like to turn that into a 3.14 lsd
the ZX14 really need a taller diff

i've done some searches on here and from what i've read, the easier option is to remove the lsd from the 3.62 and fit it to the 3.14?

does anyone have a step by step guide? is it do-able with little knowledge of diffs, do i need any "special tools" i've seen one on ebay for undoing the bearing casulated nut thingys

any advice before i ruin two good working diffs

fesycresy - 6/10/11 at 02:30 PM

Send it to Road and Race Transmissions, Phil did mine.

Johneturbo - 6/10/11 at 02:40 PM

Ok thanks that's an option i guess

mcerd1 - 6/10/11 at 02:54 PM

Johneturbo - 6/10/11 at 03:09 PM

thanks for the links, nice to see what it looks like once taken apart

does seem there are rather a lot "special tools" though :/

mark chandler - 6/10/11 at 05:29 PM

Easy to do yourself, the only hard bit is undoing the ends but someone was selling a tool on Ebay to mesh for Ł20, I just laid a rod across the top after soaking overnight in penetrating oil, had to warm the outside where the threads are as well with a blow torch to get moving.

The pinion bolt is deep, I purchased a cheap shallow impact socket from Halfords, cut in half and welded a short piece of scaffold tube to space, voila super deep socket.

Being locost I just purchased the seals, reused the bearings and adjusted by hand.

Install the pinion and tighten up until all endfloat has gone, install the crownwheel and twiddle in the sides until the crown starts to bind then backed off a couple of notches, then wind the crown wheel into mesh turning both sides evenly with the pinion until you can feel it starting to bind then back off a tad.

Regards Mark

[Edited on 6/10/11 by mark chandler]

Johneturbo - 6/10/11 at 07:20 PM

Hey Mark
As i'm just putting the lsd into the 3.14 will i also be adjusting/removing the pinion

i thought it was a case of removing the outer casulated bearing housing then removing the crownwheel/housiing then fitting the lsd to the crownwheel then re-assemble

i've seen the tool you're talking about on ebay

blakep82 - 6/10/11 at 07:25 PM

pretty sure you need to change the pinion too! not just adjust.

Johneturbo - 7/10/11 at 01:42 PM

Like i've said i'm no expert on diffs...but am i not just unbolting the lsd from the crownwheel of the 3.62 and bolting onto the 3.14 crownwheel? like this section here

Liam - 7/10/11 at 03:47 PM

quote:
Originally posted by Johneturbo
Like i've said i'm no expert on diffs...but am i not just unbolting the lsd from the crownwheel of the 3.62 and bolting onto the 3.14 crownwheel? like this section here

That's what I have always heard - no need to mess about with the pinion. You're sticking the LSD mechanism into the existing 3.14 diff basically. Just need to get the sidewaysness set up right by twiddling the castly things.

blakep82 - 7/10/11 at 03:56 PM

quote:
Originally posted by Liam

quote:
Originally posted by Johneturbo
Like i've said i'm no expert on diffs...but am i not just unbolting the lsd from the crownwheel of the 3.62 and bolting onto the 3.14 crownwheel? like this section here

That's what I have always heard - no need to mess about with the pinion. You're sticking the LSD mechanism into the existing 3.14 diff basically. Just need to get the sidewaysness set up right by twiddling the castly things.

but his existing diff is a 3.62 LSD he wants a 3.14 LSD made from the LSD and his open 3.14.

IF the 3.14 is in a fully built ready to go case, then take the LSD out of one and put it in the 3.14

IF he's just got the open 3.14 on its own, his existing 3.62 diff and casing will need the gears taken out and the pinion and crownwheel transplanted

whatever the situation, the end result will need to have a 3.14 pinion and crownwheel. i've possibly just confused things by misunderstanding exactly what parts you have but i wouldn't want you trying to get a 3.14 crown wheel working with a 3.62 pinion!

[Edited on 7/10/11 by blakep82]

Johneturbo - 7/10/11 at 10:35 PM

Ok sorry maybe i confussed things by saying open 3.14 what i meant was open as in none lsd, not parts on the bench! its a fully working 3.14 as i've run it in the car before.
So hopefully it will be just as Liam says fit the lsd portion to my 3.14

snapper - 8/10/11 at 06:21 AM

Pinion and crown are matched, even if the pinion has the same teeth they won't mesh properly.
Most will have a different pinion tooth count as well as different crown tooth count.
If you swap, swap the matched pair.

Liam - 8/10/11 at 10:55 AM

Aarrgghh!! Look - it's really simple, folks!! (isn't it?)

The LSD mechanism from his 3.62 LSD goes into his 3.14 open diff. The end.

So the final result is the 3.14 case with the 3.14 pinion still in it (still setup - completely untouched), then the 3.14 crownwheel is still in there only now it has the LSD mechanism bolted to it rather than the open mechanism. Finally the drive flanges from the 3.62 are also inserted and clipped in.

Simples. No need to disturb the pinion shimming at all. All that is needed is to set the crownwheel mesh by adjusting the castley things.

DixieTheKid - 8/10/11 at 11:16 AM

While we are on this subject........

Do the output flanges have to be the same for each diff i.e. lobro / push in?
Do the diffs have to be the same size i.e. both 7.5"?

[Edited on 8/10/11 by DixieTheKid]

blakep82 - 8/10/11 at 12:20 PM

quote:
Originally posted by Liam
Aarrgghh!! Look - it's really simple, folks!! (isn't it?)

The LSD mechanism from his 3.62 LSD goes into his 3.14 open diff. The end.

So the final result is the 3.14 case with the 3.14 pinion still in it (still setup - completely untouched), then the 3.14 crownwheel is still in there only now it has the LSD mechanism bolted to it rather than the open mechanism. Finally the drive flanges from the 3.62 are also inserted and clipped in.

Simples. No need to disturb the pinion shimming at all. All that is needed is to set the crownwheel mesh by adjusting the castley things.

yeah, you're right, my mistake! (as i thought you had a 3.14 without case)
so yes, work away! sorry! just wanted to make sure you didn't get yourself in any trouble with wring gears and stuff

Johneturbo - 20/10/11 at 02:15 PM

I thought i'd do a quick update i've now got my 3.14 built up with the LSD fitted the hardest job was undoing the castlelasted bearing housing side the 3.62lsd was a real bugger to get loose

I made up this tool not my idea i stole it from a website works a treat, its just a 3" oil filter socket with a 8mm studding i did weld on a 19mm nut, as i found the small 3/8 socket attachement wasn't meaty enough as it rounded up

i've got the backlash where it feels right but i've ordered a dial indicator (only Ł15) just to check.
it wasn't a bad a job as i thought it might be

here's a photo of my tool

Differential Tool

Differential Tool