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Series3 GT
9th September 2012, 10:02 PM
G'day all, I've got a few questions about swapping gearboxes. My IIA's gearbox is very noisy an being a IIA box you crunch gears occasionaly. I've got a Series 3 box that came out of my III that i'm using for my 100" project, the series 3 box will be quieter and have syncro. So what will i need to do to fit the series 3 box to my IIA.

Landy Smurf
9th September 2012, 10:16 PM
as far as i know nothing

Series3 GT
9th September 2012, 10:27 PM
The IIA seems to have a different bellhousing but I assume they're the same pattern. Is the clutch the same set up.

mick88
10th September 2012, 07:03 AM
Different clutch throw out system so a bit more in it than just changing the box over.
Still a reasonably easy task though.


Cheers, Mick.

Series3 GT
10th September 2012, 07:24 PM
Different clutch throw out system so a bit more in it than just changing the box over.
Still a reasonably easy task though.


Cheers, Mick.
What will i need to do with the clutch throw out to make it suit the IIA.

Slunnie
10th September 2012, 07:27 PM
The hydraulics and lines go over to the other side of the gearbox.

Also check your bellhousing bolt pattern matches. Indicated by the top bolts at either 12 oclock or 11 and 1.

Series3 GT
10th September 2012, 07:50 PM
I looked at the two boxes yesterday and both are on the right hand side so does it mean anything about the Series 3 box.

Lotz-A-Landies
10th September 2012, 07:51 PM
Your head read! :D

Late SIIa boxes are in many ways stronger than early SIII boxes and far cheaper to repair than any SIII box.

You need to swap like engine for like, i.e. 4cyl SIIa box for SIII 4cyl box. Otherwise you have to swap bellhousings which means opening the SIII box.

The SIII use a diaphragm clutch pressure plate where the SIIa uses a finger pressure plate with a smaller friction plate and you will need a longer brake hydraulic hose to go over to the other side.

Series3 GT
11th September 2012, 09:28 PM
Well I've got a SIII box sitting around and a IIA with a box that needs fixing. I'll eventually fix the IIA box but that'll be down the track at the moment but I definetly will because its got a PTO on the back of it. As I said before the IIA and III box have the clutch slave cyl on the same side as each other and same slave cyl. Both boxes are 4cyl so should the bell housing fit? Will I need to do any clutch mods.

JDNSW
12th September 2012, 05:54 AM
Just to lay out the (fitting) differences. Series 1,2, 2a and 3 four cylinder boxes have the same bell housing to flywheel housing fitting.

Clutch release mechanism on Series 1,2,2a (except some very late S2a) have the release bearing operated by a fork internal to the gearbox, with a horizontal shaft coming out the RH side (for RHD) of the box with an external slave cylinder and bell crank to turn the shaft. Series 3 has the slave cylinder on the LH side, with the release fork on a peg in the bell housing.

The series 3 clutch is, as Diana has said, is a diaphragm clutch, where most Series 2a use coil springs - but some use a different diaphragm clutch plate, as the position of the release bearing for the two types of release bearing is different.

If your "Series 3" box has the release mechanism on the RH side, it is either a Series 2/2a box, or it has been modified to fit a Series 2/2a. The clutch release mechanism and bell housing can be swapped to fit a box to either 2/2a or 3, but this involves disassembling the box.

Gearbox noise depends on bearing condition rather than type of box (except for 1st). The PTO will fit either box. As Diana says, the late 2a box is usually considered the pick of them as far as strength and durability goes.

John

Series3 GT
12th September 2012, 07:54 PM
The box I want to fit came out of a SIII ute and its on the right hand side so it could be another box or the engines been swapped and redone to suit. As for the gearbox noise, the bearings are in good condition because I only replaced them a year or two ago, the noise is the main shaft is damaged. You can hear the noise the most in 1st but you can still hear it up to 4th but its a bit quieter. I remember when I had the box out that the clutch had three prongs in the middle so I'm not sure what it was.

Series3 GT
16th September 2012, 06:13 PM
Well the new gearbox is in and it's fantastic. The box went straight in without a problem. It's nice and quiet but I don't think its a SIII box because I have to double clutch it. I even have brakes now, we fixed them while we were there.

JDNSW
17th September 2012, 05:35 AM
Thanks for letting us know the end result.

John