Series 2 to Series 3 gearbox change

[peterg1001]

I'm thinking about swapping the Series 2 gearbox out for a Series 3, to get the synchro and diaphragm clutch.

Can anyone out there give me a set of bullet points of things I need to consider, and to buy/acquire in order to do the job?

Thanks, Peter

[JDNSW]

You can fit a diaphragm clutch to the 2a, but it is a special pressure plate with a built in spacer. It is possible you already have one (should be able to see if you take the gearlever assembly off and peer in the hole in the flywheel housing this uncovers).

To change the Series 2a to Series 3, apart from the box with bell housing, you will need the Series 3 clutch, clutch slave cylinder and pushrod, clutch fork, release bearing, pilot bush (same as 2a). clutch hydraulic pipe from the master cylinder to LH side, clutch hydraulic hose.

Points to watch - bell housing is different from six to four - make sure your new box is the same as the one you have. Probably a good idea to change out the master cylinder while you are at it.

Personally I prefer the 2a box to use, and they are generally considered more robust, but I do think that the S3 clutch arrangement is probably more trouble free.

John

[peterg1001]

Thanks John, I don't mind the Series 2 box, but my left knee is getting to a point where I need to take any available precautions available to keep it working.

There's a Series 3 box and 6 cyl engine going on ebay at the moment, but it sounds as if there would be some significant bits to add to get it onto my 4 cylinder.

Experience suggests that the acquisition of a bunch of little bits is an expensive undertaking.

Peter

[JDNSW]

Thanks John, I don't mind the Series 2 box, but my left knee is getting to a point where I need to take any available precautions available to keep it working.

There's a Series 3 box and 6 cyl engine going on ebay at the moment, but it sounds as if there would be some significant bits to add to get it onto my 4 cylinder.

Experience suggests that the acquisition of a bunch of little bits is an expensive undertaking.

Peter

The Series clutch is not that heavy, although the diaphragm clutch is lighter, but you might want to consider a remote brake power assist unit to reduce the clutch effort. They are not common, but they can be found.

John

[peterg1001]

The Series clutch is not that heavy, although the diaphragm clutch is lighter, but you might want to consider a remote brake power assist unit to reduce the clutch effort. They are not common, but they can be found.

John

Thanks John, I'll try a power booster on the clutch circuit. I can get a PBR VH44 for about $300, and that can be my next little project.

Stand by for photos . . .

Peter

[pop058]

Thanks John, I'll try a power booster on the clutch circuit. I can get a PBR VH44 for about $300, and that can be my next little project.

Stand by for photos . . .

Peter

yes please

[NiteMare]

i'd also go along with the power assist on the clutch, no more than 1.6:1 ratio in my opinion, probably less...

i drive both the series 3 and series 2a with 9.5" diaphragm clutches and feel there is very little difference in the weight of them, i've not driven one using the 9" three fingered clutch cover (early 2a) so can't comment on that...

i did find recently when i changed my clutch (only changed because i was sick of the shudder spring rattle when idling) in the S3 that there was a significant weight difference with the new one (reclaimed out of my parts bin) even though the cover plates were identical make/appearance, i've no idea why though

[JDNSW]

i'd also go along with the power assist on the clutch, no more than 1.6:1 ratio in my opinion, probably less...

i drive both the series 3 and series 2a with 9.5" diaphragm clutches and feel there is very little difference in the weight of them, i've not driven one using the 9" three fingered clutch cover (early 2a) so can't comment on that...

i did find recently when i changed my clutch (only changed because i was sick of the shudder spring rattle when idling) in the S3 that there was a significant weight difference with the new one (reclaimed out of my parts bin) even though the cover plates were identical make/appearance, i've no idea why though

Pressure to disengage a clutch decreases as the plat (and pressure plate) wear, as the spring(s) (either coil or diaphragm) are not tensioned as much - eventually the pressure of them is not enough to grip the plate and you have slip. This is reflected in the pedal pressure needed. Could this be the reason for the difference?

John

[NiteMare]

Pressure to disengage a clutch decreases as the plat (and pressure plate) wear, as the spring(s) (either coil or diaphragm) are not tensioned as much - eventually the pressure of them is not enough to grip the plate and you have slip. This is reflected in the pedal pressure needed. Could this be the reason for the difference?

John

nope the friction plate i used was of a greater thickness than the old one and the cover plate was almost brand new ...

the only possible thought i have for the old cover plate giving greater weight is that this motor does quite a lot of off roading and there was a fair bit of soil sprayed around in the flywheel housing along with a little showing on the cover plate, maybe it had started to rust in places inside itself and was giving extra load, who knows

[Warb]

The original SII workshop manual lists different springs for the diesel and petrol clutches, the diesel having heavier springs, and also states that the springs from the "Rover 105" can be used with "5% increase in pedal effort". Maybe the two clutches in question had different springs fitted?