Series 3 gearbox into a Series 1

[101RRS]

I know there are threads on putting a series 3 gearbox into a series 1 but I cannot find them.

Having owned a few series 1s in the past and had one as an everyday driver for 7 years I know how to handle the no synchro box but these days I would just prefer to have it easy.

So a simple question - can a series 3 box just bolt up to the series 1 bell housing and mechanical clutch (I do not want to change to a hydraulic arrangement).

If not a simple bolt up what are the issues I will have to address - eg gearbox mounts, connected to a series 1 transfer case, need to change series 3 box gear ratios etc

Also would the Series 1 2 litre (either spreadbore or siamese) be able to pull high speed diffs and would it just be a bit much?


Thanks

garry

[JDNSW]

Not that simple. The mechanical clutch mechanism is integral to the bell housing, which is also the front cover of the gearbox. While the dimensions and bolt arrangement are similar, the "gotcha" is that unless I am mistaken, the bearing size on the mainshaft of the gearbox changed between Series 1 and Series 3. Even given this, it can probably be done, although some design work and machining would be required.

It would be easier to design and fabricate a master cylinder set up to operate off the existing clutch pedal.

Note that the bell housing to flywheel housing pattern differs between the 2l and the 2.25l, although I think the six is the same as the 2l.

I would not want high speed diffs on a 2l motor, although they would probably work if you always drove with driver only in a soft top.

And then there is the point that Series 1 are becoming sufficiently collectible to give most people pause at moving away from originality.

[101RRS]

Ok thanks John - you have given me the answers I was after. So not so simple as I was hoping. Your last line is why I wanted to just do the box.

I have a couple of dead series 1 boxes lying around so might see if I can find a dead series 3 box and see what fabrication is required.

So in view of John's response, another general question - is it possible to change the series 1 box internals to make first have synchro?

Just thinking aloud with the thread. Need to get other's ideas before doing something or doing nothing.

Cheers

garry

[JDNSW]

The synchro box is developed from the old box (originally designed for a Rover car in 1932 unless I am mistaken), but I think you will find that to shoehorn in the synchro in the old box they had to make all sorts of minor adjustments to sizes and positions of parts, but it would be interesting to have the two boxes apart and compare in detail. It may be possible, but I suspect it would be a lot of work for uncertain success.

As an aside, gear ratios changed over the years, but not enough to worry about. Overall gearing was the same in 4H and 1L, just the ones in between changed. You can get a lower 1L by mix and match the transfer and main box.

As far as I am aware, any Series transfer box will fit any Series main box, with a few minor fixes (except stage 1). Also note that there is no difference between petrol, diesel and six cylinder boxes (or the same vintage), except that the bell housing to flywheel housing pattern is different - six and S1 are different from the diesel and 2.25. (Again, Stage 1 is different)

[101RRS]

Thanks John - helpful as always [bigsmile1].

[123rover50]

Are you starting work on the wagon Garry?
Another daily drive?[bigwhistle]

Keith

[101RRS]

No not yet but just thinking out aloud in anticipation - you might suss all this out for me and get back to me [bigsmile1].

For some reason it has a siamese engine in it that obviously has to come out. I have a spreadbore sitting in the garage and is something that I can work on before the rest of the vehicle - at the same time i would also look at the gearbox, tfr case and clutch. When i had my previous series 1 on the road I was able to double shuffle on the down shift OK but these days, many years older I really dont feel like going through that all the time - hence the thought of a series 3 box but not if it means changing the clutch etc as with this vehicle originality is important as John mentioned.

Cheers

Garry

[JDNSW]

I learnt to drive on cars with no synchro on any gears, hence had no issues when I first drove Landrovers in the late 1950s. But then all the cars I drove from 1970 - 1990 had all synchro. I had no difficulties recovering the skills when I bought my current 2a in 1990. I think you will find it comes back very quickly.

[goingbush]

Garry sounds like you should have a drive of my Electric Series , no need to ever use 1st or 2nd in daily driving, & usually just take off it top & leave it there , 3rd is good for brisk acceleration or hills , Would be perfect for a Series One box . need 4.7 diffs though.

[QRS40]

If you are needing to replace the engine either way, originality won’t necessarily be as relevant will it? Sure it won’t get ‘top dollar’ like a museum peice but is that what you want anyway? Particularly in future I think drivability (as long as any mod is sympathetic, eg still series Land Rover) will be a drawcard not a drawback, for most cars. After all, they are here to drive not just be looked at.

Full disclosure- I’m probably a bit biased as I have an s1 with a s2 engine, s3 gearbox, s1 transfer box, and 3.5 diffs. It’s no concourse contender but it’s on full rego and I can drive relatively safely on the motorway. And it still delights kids and other motorists when I’m out and about.

[101RRS]

If you are needing to replace the engine either way, originality won’t necessarily be as relevant will it?

It does not have the correct engine in it (siamese) and I will put the correct spreadbore engine in it.

[Blknight.aus]

a SII box will work and a SIII box and be back fitted to a SII box. BUT...

it has to be a late II box and an early III box AND you have to do some custom bearing selection AND some machining BUT..

yes, you can effectively make a SIII box fit into an SI if you have the gear, the verniers and the patients with a good bearing guy.

The SI engine will pull the 3.54's but its not going to enjoy 4th or work well off road. 4.11's is about as good as you're going to get and you have to be on the SI small rubber...